Discovery and Optimization of 2 H-1λ2-Pyridin-2-one Inhibitors of Mutant Isocitrate Dehydrogenase 1 for the Treatment of Cancer

Article abstract of DOI:10.1021/acs.jmedchem.1c00019

Neomorphic mutations in isocitrate dehydrogenase 1 (IDH1) are oncogenic for a number of malignancies, primarily low-grade gliomas and acute myeloid leukemia. We report a medicinal chemistry campaign around a 7,7-dimethyl-7,8-dihydro-2H-1λ2-quinoline-2,5(6H)-dione screening hit against the R132H and R132C mutant forms of isocitrate dehydrogenase (IDH1). Systematic SAR efforts produced a series of potent pyrid-2-one mIDH1 inhibitors, including the atropisomer (+)-119 (NCATS-SM5637, NSC 791985). In an engineered mIDH1-U87-xenograft mouse model, after a single oral dose of 30 mg/kg, 16 h post dose, between 16 and 48 h, (+)-119 showed higher tumoral concentrations that corresponded to lower 2-HG concentrations, when compared with the approved drug AG-120 (ivosidenib).

Full text of DOI:10.1021/acs.jmedchem.1c00019

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Article
Discovery and Optimization of 2H‑1λ2‑Pyridin-2-one Inhibitors of
Mutant Isocitrate Dehydrogenase 1 for the Treatment of Cancer
Jason M. Rohde, Surendra Karavadhi, Rajan Pragani, Li Liu, Yuhong Fang, Weihe Zhang,
Andrew McIver, Hongchao Zheng, Qingyang Liu, Mindy I. Davis, Daniel J. Urban, Tobie D. Lee,
Dorian M. Cheff, Melinda Hollingshead, Mark J. Henderson, Natalia J. Martinez, Kyle R. Brimacombe,
Adam Yasgar, Wei Zhao, Carleen Klumpp-Thomas, Sam Michael, Joseph Covey, William J. Moore,
Gordon M. Stott, Zhuyin Li, Anton Simeonov, Ajit Jadhav, Stephen Frye, Matthew D. Hall,* Min Shen,*
Xiaodong Wang,* Samarjit Patnaik,* and Matthew B. Boxer
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ABSTRACT: Neomorphic mutations in isocitrate dehydrogenase
1 (IDH1) are oncogenic for a number of malignancies, primarily
low-grade gliomas and acute myeloid leukemia. We report a
medicinal chemistry campaign around a 7,7-dimethyl-7,8-dihydro-
2H-1λ2-quinoline-2,5(6H)-dione screening hit against the R132H
and R132C mutant forms of isocitrate dehydrogenase (IDH1).
Systematic SAR efforts produced a series of potent pyrid-2-one
mIDH1 inhibitors, including the atropisomer (+)-119 (NCATS-
SM5637, NSC 791985). In an engineered mIDH1-U87-xenograft
mouse model, after a single oral dose of 30 mg/kg, 16 h post dose,
between 16 and 48 h, (+)-119 showed higher tumoral
concentrations that corresponded to lower 2-HG concentrations, when compared with the approved drug AG-120 (ivosidenib).
cellular behavior.11−13 For example, 2-HG inhibits α-KG-
INTRODUCTION
■
dependent enzymes,14,15 and direct evidence exists for
Over the past decade, mutant isocitrate dehydrogenases 1
inhibition of α-KG-dependent histone and DNA demethylases
(mIDH1) and 2 (mIDH2) have emerged as important targets
by 2-HG leading to elevated histone methylation, with
for treating a range of malignancies.1,2 Normal (wild-type,
consequent impact on gene expression and cell differ-
WT) IDH1 or IDH2 protein catalyzes the conversion of
entiation.16
isocitrate to α-ketoglutarate (α-KG, also called 2-oxoglutarate,
Both mIDH1 and mIDH2 are attractive therapeutic targets
2-OG), using NADP+ as a cofactor.3 Critical work has
due to their genetic gain-of-function, which confers an
demonstrated that some acute myelogenous leukemias
oncogenic role that is amenable to detection via both tumor
(AMLs) and gliomas possess heterozygous somatic mutations
gene sequencing and metabolite (2-HG) measurement.17
of IDH1 at position R132 and IDH2 at R140 or R172.4−6
Moreover, specific inhibition of mIDH1/2 should not produce
Analysis of clinical samples has shown that the majority of low-
target-related clinical side effects as WT IDH’s function would
grade gliomas and ∼20% of AML have IDH1 or IDH2
be unaffected. In 2017, only after ten years since the first
mutations, and a range of other solid tumors such as
reports of the role of IDH1/2 mutations in cancer, the FDA
chondrosarcoma, cholangiocarcinoma, colon, pancreatic, and
approved the mIDH2 inhibitor enasidenib from Agios/
prostate cancer have also been found to carry IDH1/2
Celgene for treatment of relapsed or refractory AML (R/R
mutations, although to a lesser degree.1,7
AML).18 In 2018, the FDA granted priority approval to Agios’
The canonical mutations to IDH1 and IDH2 confer a
mIDH1 inhibitor AG-120 (ivosidenib) for patients with R/R
neomorphic (gain-of-function) activity. While WT IDH1
produces α-KG, α-KG is the substrate of mIDH1, which in a
Received: January 6, 2021
Published: April 6, 2021
pseudo-reverse reaction using NADPH produces R-2-hydrox-
yglutarate (2-HG).8,9 An analysis of serum 2HG levels in AML
patients bearing IDH1 or IDH2 mutants showed a clear
elevation (median 2HG of 3004 ng/mL) compared to patients
with WT IDH (median 2HG of 61 ng/mL).10 This 2-HG
“oncometabolite” has been shown to play a role in modifying
https://doi.org/10.1021/acs.jmedchem.1c00019
© 2021 American Chemical Society
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Figure 1. (A) Schematic for primary biochemical qHTS assay; (B) assay performance as measured by Z′ factor and S/B ratio; (C) workflow for the
identification of small-molecule inhibitors of mutant IDH1; and (D) dose-dependent activity of hit 1 against R132H mIDH1, IDH-WT, and in a
readout interference counterscreen.
AML harboring IDH1 mutations as measured by the Abbott
RealTime IDH1 assay.19 In May 2019, ivosidenib was
approved as first-line treatment for AML with IDH1 mutation
in patients who are at least 75 years old or who have
comorbidities that preclude the use of intensive induction
chemotherapy.19 Agios continues to take ivosidenib through
multiple clinical trials, notably, toward AML in combination
with the chemotherapeutic drug azacytidine and toward glioma
and cholangiocarcinoma in patients harboring mIDH1.20 Agios
is also advancing its pan mIDH oral inhibitor AG-881
(vorasidenib) in trials with patients with advanced solid
tumors (including gliomas) and low-grade glioma.20,21 In
addition to this, Novartis and Bayer have also advanced IDH
inhibitors IDH305 and BAY1436032 mIDH1 to clinical
trials.22,23 In 2019, an updated succinct review of all reported
classes of preclinical and clinical small-molecule mIDH
inhibitors was published.24 It included Agios’ tool mIDH1
inhibitor AG-5198,25 probe molecules from Sanofi and
GlaxoSmithKline,26,27 and CNS penetrant FT-2102 from
Forma Therapeutics, Inc.28
We had been involved in an early assay development and
screening program that produced the phenyl-glycine analogue
ML309 as a potent inhibitor of R132H mIDH1.29,30 We also
developed a panel of biochemical and cell-based assays to
enable inhibitor discovery campaigns and aid comparison to
known mIDH1 probe and experimental therapeutic inhib-
itors.31 Here, we fully describe the hit-to-lead medical
chemistry campaign based on a 7,7-dimethyl-7,8-dihydro-2H-
1λ2-quinoline-2,5(6H)-dione mIDH1 inhibitor chemical series
that also emerged as a screening hit besides the chemotype that
was optimized to ML309. Optimization led to the discovery,
separation, and biological characterization of stable atro-
pisomers from a 1-arylpyridin-2(1H)-one subseries. Exemplary
analogue (+)-119 is used to demonstrate 2-HG reduction in a
pharmacokinetic/pharmacodynamic (PK/PD) model with
ivosidenib as a comparator molecule.
Our project was supported by the National Cancer
Institute’s (NCI) Experimental Therapeutics (NExT) Program
facilitated within the NCI Chemical Biology Consortium
(CBC). The goal of CBC’s NExT Program is to bring together
government, industry, and academic groups to enable a team-
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Scheme 1. General Analogue Synthesis
Table 1. Core Modifications and SAR
biochemical
IDH1 R132H
% inhibition SD at 38 μM
IDH1 R132C
% inhibition SD at 38 μM
a
a
compound
IC50 (μM) SD
IC50 (μM) SD
1
2
1.6 0.2
>38
84
7
1.0 0.3
>38
85
9
3
>38
>38
4
5
6
7
8
9
10
3.6 0.5
3.0 0.3
87
96
62
38
35
3
4
1
1
0
64
76
43
29
36
32
65
5
2
1
4
2
3
4
1.7 0.2
8.0 2.4
2.3 0.0
75 15
84
1
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled R132H and R132C mIDH1 assays (average of N = 3). IC50 values are
reported only for compounds where ≥75% inhibition of enzyme activity was observed at the highest concentration tested (38 μM).
science approach toward the discovery and development of
novel therapeutics (https://next.cancer.gov).
from the endpoint and normalized against control wells [no
enzyme as the positive control and dimethyl sulfoxide
(DMSO) as the negative control]. The percent inhibition at
each of the concentrations of inhibitor tested was plotted and
modeled using a four-parameter logistic fit using in-house
software to determine the compound IC50 values. There were
nearly 600 1536-well plates in the primary qHTS, which
included library plate sets and a couple of DMSO plates
inserted in the beginning and end of the screening for data
correction purposes. The assay was performed well with an
RESULTS AND DISCUSSION
■
A diaphorase/resazurin-coupled assay for the IDH1 R132H
mutation was developed and utilized to screen our in-house
collection of nearly 390,000 small molecules (Figure 1A). In
this quantitative high-throughput screen (qHTS), the assay
was performed at six concentrations ranging from 76 μM to 2
nM. The inhibition associated with each well was computed
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Table 2. Thiazole Substitution SAR
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled R132H and R132C mIDH1 assays (average of N = 3). IC50 values are
reported only for compounds where ≥75% inhibition of enzyme activity was observed at the highest concentration tested (38 μM).
average Z′ factor of 0.60 and an S/B ratio around 3.2 (Figure
1B). Analysis of these dose−response curves resulted in 2155
testing concentration. Among these 2155 inhibitors, 769 were
identified as high-quality inhibitors with single or dual
compounds that showed inhibition over 30% at the highest
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Table 3. Pyridone Aryl Substituent SAR
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled R132H and R132C mIDH1 assays (average of N = 3). IC50 values are
reported only for compounds where ≥75% inhibition of enzyme activity was observed at the highest concentration tested (38 μM).
asymptote curves and greater than 50% inhibition (Figure 1C),
representing 0.2% of the chemical library.
1D, compound 1 displayed inhibition with an IC50 of 1.6 μM
against R132H mIDH1, with no readout interference and off-
target activity against WT IDH1. In addition to the R132H
mutant,32,33 we also developed the analogous assay for the
R132C mIDH1, a frequent mutation in AML and intracranial
chondrosarcoma,34,35 and we sought to develop a class of
inhibitors capable of targeting both mutations (1 had an IC50
of 1.0 μM against R132C mIDH1).
Despite the moderate structural complexity of hit 1, it was
readily accessible via an efficient one-pot, multicomponent
coupling (Scheme 1). Combining dione I and acetal II well
resulted in quick conversion to reactive vinylogous amide III.
The addition of a base (piperidine or KOtBu) to nitrile IV
generated an anion that when added to intermediate III,
afforded intermediate V by a Michael addition−elimination
sequence. Finally, incorporation of aniline Ar2NH2 VI provided
the pyridinone ring system through cyclodehydration. This last
two-step sequence was sufficiently tolerant of diverse
substitution on both nitrile IV and aniline VI and was
The 2155 hit compounds identified from the screen were
thoroughly evaluated for both potency and percent inhibition;
the autofluorescent compounds and promiscuous inhibitors
(compounds that show activity in more than 20% of assays
within historical screening data at NCATS) were eliminated
from follow-up examination. A total of 761 prioritized hits
were retested and screened in 12-pt dose−response in the
primary screening assay to reconfirm the activity. The
compounds were further tested in a readout interference
assay and IDH1-WT selectivity assay to refine and triage initial
screening hits (assay hit triage workflow shown in Figure 1C).
After structural clustering analysis and assessment of synthetic
tractability to eliminate compounds that did not offer good
starting points for hit-to-lead optimization, a 7,7-dimethyl-7,8-
dihydro-2H-1λ2-quinoline-2,5(6H)-dione chemotype (repre-
sentative hit 1, Figure 1) with good starting potency and
selectivity over WT IDH1 was identified. As shown in Figure
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Table 4. Pyridone Aryl Substituent SAR Continued
biochemical
R4
IDH1 R132H
IDH1 R132C
a
a
compd
R5
IC50 (μM) SD
% inhibition SD at 38 μM
84
64 17
IC50 (μM) SD
% inhibition SD at 38 μM
1
OMe
OMe
OMe
OMe
OMe
OMe
OMe
OMe
OMe
OMe
OMe
OEt
5-OMe
3-OMe
4-OMe
6-OMe
3-CO2H
4-CO2H
5-CO2H
6-CO2H
6-Me
3-N (Py)
5-N (Py)
5-OEt
6-OEt
6-Me
1.6 0.2
7
1.0 0.3
85
35
9
3
53
54
55
56
57
58
59
60
61
62
63
64
65
66
>38
2.4 0.1
>38
1.6 0.2
87
82
2
2
75
65
43
86
108
72
80
7
2
6
4
1
1
1
14
1
>38
12
1
108
102
81
2
3
14
1
0.91 0.06
2.1 0.1
1.0 0.1
>38
0.16 0.01
0.39 0.03
0.79 0.18
0.69 0.05
2.0 0.1
2
1
97
1.3 0.2
>38
0.064 0.004
0.16 0.02
0.50 0.09
0.24 0.05
85
76
89
89
1
4
1
2
75
86
86
82
1
7
3
4
OEt
Et
Et
6-Et
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled R132H and R132C mIDH1 assays (average of N = 3). IC50 values are
reported only for compounds where ≥75% inhibition of enzyme activity was observed at the highest concentration tested (38 μM).
conducted in one pot, requiring only a single solvent exchange
from isopropanol to acetic acid.
was essentially equipotent to 1 against R132H mIDH1 but lost
efficacy toward the R132C mutant. Substitution at the 4-
position of the thiazole in the form of a biaryl linkage seemed
optimal in contrast to either substitution at the 5-position or
modification to a fused ring system, with analogues 12−14
displaying significant losses in activity. Replacement of the
thiazole with a variety of diazoles 15−22 had a dichotomic
effect on mIDH1 potency with imidazoles 17 and 18, pyrazoles
19 and 20, maintaining activity, and the remainder of the
analogues (15, 16, and 21−26) experiencing significant losses
in biochemical potency. This SAR led us to believe that
maintaining a nitrogen positioned akin to the thiazole nitrogen
(3-position highlighted in 1, Table 2) was important, while a
nitrogen at the 2-position abrogated activity (16, 20, and 21).
Further supporting this observation, expansion of the ring to a
benzene (23−24; meta- and para-substitution) proved
unfavorable with complete loss in mIDH1 inhibitory activity,
while substitution with a 2,6-disubstituted pyridine retained
some activity (25). In an attempt to open the thiazole ring, we
synthesized amide 26, but this proved to be a detrimental
variation of the thiazole. Thus, the thiazole segment, much like
the cyclohexanone moiety, was not amenable to significant
modification.
Tables 3 and 4 showcase the SAR exploration of the aryl
group attached to the pyridone nitrogen (R1). Synthetically,
this region was readily modifiable since it was made from the
last step in Scheme 1; thus, it was extensively investigated.
Given the steric congestion about the pyridinone aryl linkage,
we posited that the orientation of the pyridinone orthogonal or
perpendicular to the arene may be optimal, especially given the
2-methoxy substituent present in the hit molecule. Along these
lines, removal of the two methoxy groups in the form of
analogue 27 resulted in a loss of activity against both mutant
forms of IDH1 (Table 3). Installation of a variety of ortho-
We initiated the optimization of the 7,8-dihydroquinoline-
2,5(1H,6H)-dione ring system by first establishing the essential
components necessary for activity in this region. The
cyclohexanone ring proved was necessary as monocyclic
analogues 2 and 3 were completely inactive. The carbonyl
functionality appeared to play a lesser role as des-carbonyl
analogues 4 and 5 were only slightly less potent and/or
efficacious against the R132H and the R132C IDH1 mutant
enzymes (Table 1). The removal of the methyl groups (6),
contraction of the ring (7), and aromatization (8) all resulted
in significant losses in activity. We also incorporated a
heteroatom into this ring system with analogues 9 and 10,
and while amine 9 was less potent, lactam 10 displayed
comparable activity to the hit, showing that the amide
functional group was well-tolerated. In addition to focusing
primarily on target potency, we closely monitored the activity
of our molecules against WT IDH1. Fortunately, none of the
molecules in this series showed activity against WT IDH1
(IC50 > 57 μM) nor did most of the compounds in the
remainder of the hit-to-lead campaign described below. This
brief survey of the core structure−activity relationships (SARs)
highlighted the importance of the geminal methyl groups, and
the six-membered ring as requirements for biochemical
potency.
The next structural element investigated was the thiazole
ring (Table 2). Given its proximity to the carbon center that
acts as a nucleophile during the conversion of III to V, as
shown above in Scheme 1, many of the modifications to the
thiazole ring required developing new synthetic sequences
which resulted in synthetic challenges and poor throughput; as
a result, Table 2 has analogues that lack the para-chloro
substituent present in the hit. The des-chloro compound 11
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Table 5. Ring-Opened Core Modifications
biochemical
core
IDH1 R132H
% inhibition SD at 38 μM
IDH1 R132C
% inhibition SD at 38 μM
a
a
IC50 (μM) SD
IC50 (μM) SD
1
1.6 0.2
2.3 0.0
0.69 0.05
>38
7.2 0.5
>38
84
84
89
7
1
2
1.0 0.3
85
65
82
4
4
4
10
66
67
68
69
70
0.24 0.05
>38
102
1
72
3
>38
1.5 0.0
87
3
64
5
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled R132H and R132C mIDH1 assays. IC50 is reported only for
compounds with >75% inhibition at 38 μM, the highest concentration tested.
Scheme 2. General Amide Synthesis
substituents regained target potency in the instance of small
alkoxy substituents (28−30) and an ethyl substituent (32).
The ortho-methyl-substituted compound 31 was active but did
not show inhibition beyond 75% at the highest concentration.
Analogues with larger R1 groups, such as 2-iPr (33) and 2-Ph
(34), or with free hydroxyl (35) and larger alkoxy groups (36
and 37), or nitrogen-containing substituents (38−40)
provided only partial inhibition of the mutant enzymes even
at the top concentration tested (38 μM). Interestingly, the only
polar substituent to maintain activity was the 2-carboxylic acid
analogue 41. With 2-halo substitutions, a smaller 2-F (42) lost
activity against both IDH1 mutants, but a 2-Cl (43) was
equipotent to 1 for R132H, emphasizing the need of an ortho-
substitution large enough to force the pyridone ring to be
orthogonal to the central bicyclic core and restrict rotation.
Notably, both 2-trifluoromethyl (44) and 2-trifluoromethoxy
(45) analogues exhibited improved mIDH1 activity over 1,
reiterating that varying electronic character was tolerated at the
2-position. Further modifications by extension with a carbon
spacer (48) or conversion to alkyl groups (49 and 50) were
not tolerated. A handful of heterocyclic replacements such as a
2-pyridyl ring (46) were also evaluated; most heterocycles
(analogues not shown) showed diminished activities, whereas
2,3-disubstituted thiophenes, such as compounds 51 and 52,
served as viable replacements.
Probing further substitution of the pyridinone arene, we
aimed to develop a more complete understanding of this
region of the pharmacophore (Table 4). By keeping the 2-
OMe group constant and walking the second methoxy group
around the remaining positions of the ring (53−55), the
importance of the relative 2,5- and 2,6-substituent arrange-
ments became apparent. A similar scan was conducted with a
polar carboxylic acid group (56−59). The 2-OMe,6-CO2H-
disubstituted compound 59 showed potent inhibition of both
R132H and R132C mutant isoforms. Within this subset (1 and
53−59), we also noticed that the placement of a substituent at
the 4-position led to a profound reduction of activity (54 and
57). A 2-OMe,6-Me compound (60) was also potent
indicating that an alkyl group could also be tolerated at the
6-position. Despite the synthetic challenges associated with
substituting the phenyl for a pyridine given the diminished
nucleophilic reactivity of amino pyridines in the conversion of
V to VII (Scheme 1), we synthesized analogues 61 and 62.
These analogues demonstrated that this change was only
tolerated if the pyridine nitrogen was in the 3-position, next to
the 2-OMe substituent (61). We then moved on to change the
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Table 6. Amide Substitution SAR
biochemical
IDH1 R132H
IDH1 R132C
a
a
compd
R4
R5
IC50 (μM) SD
% inhibition SD at 38 μM
IC50 (μM) SD
% inhibition SD at 38 μM
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
Me
Me
iPr
tBu
iBu
H
Me
H
H
H
H
H
H
H
H
H
H
H
H
H
1.5 0.0
1.2 0.1
2.8 0.2
87
98
47
65
3
3
1
5
64
86
54
49
56
5
1
2
4
1
2
5
4
1
2
2.0 0.1
>38
0.81 0.05
2.0 0.1
0.73 0.10
CH2CH2OH
CH2CH2OMe
CH2CO2H
CH2CH2NH2
CH2CH2NHMe
CH2CONH2
CH2CH2CH2NHMe
Ph
CH2Ph
cyclohexyl
N-piperidine
N-morpholine
N-piperazine
N-4-Me-piperazine
0.42 0.00
2.1 0.0
1.2 0.0
0.38 0.00
0.87 0.06
1.6 0.1
1.0 0.1
104
92
106
97
101
105
104
3
2
2
1
3
3
3
96
102
87
89
11
1
2.0 0.1
0.32 0.02
3.8 0.0
96
77 14
95
69 11
41
31
65
71
93
86
0.91 0.06
0
40 21
>38
>38
1
7
3
2
2
3
51
82
103
88
0
4
3
1
4.2 0.0
0.21 0.00
2.9 0.2
4.1 0.3
1.5 0.0
1.2 0.1
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled mIDH1 R132H and R132C assays. IC50 is reported for compounds
with >75% inhibition at 38 μM, the highest concentration tested.
2-methoxy substituent to a 2-ethoxy substituent and evaluated
the 2,5- and 2,6-diOEt compounds 63 and 64. Both
compounds showed sub-micromolar IC50s. This remarkable
breakthrough in IC50 < 1.0 μM was also observed with a 2-
ethyl group when it was combined with a 6-methyl or ethyl in
65 and 66, respectively.
dimethyl acetal II was carried out by heating the two
components without any solvent to provide intermediate III
which was then condensed with functionalized nitrile IVa
under basic conditions. After the addition of aniline VIa to
ketonitrile Va and stirring with acetic acid, we discovered that
further heating was required to efficiently drive pyridinone
formation in VIIa. Finally, ester hydrolysis and HATU-
mediated amide couplings were utilized to efficiently access a
diversity of ring-opened amide analogues (VIII).
Based on this synthetic route, we surveyed a structurally
diverse set of amides, as depicted in Table 6. The tertiary
dimethylamide 71 displayed a similar activity to that of
compound 70, but larger alkyl substituents at the R4 position
provided analogues (72−74) with decreased mIDH1 activity.
Incorporation of either a nitrogen or oxygen atom at or near
the termini of an alkyl chain at the R4 position (75−81) either
maintained or even provided a boost in potency. Most
noteworthy among these were ethanaloamide 75 and 2-
aminoethyl carboxamide 78, which exhibited threefold
improvements in potency compared to analogue 70. Secondary
amides such as 82, 83, and 84 with large ring substituents such
as phenyl, benzyl, and cyclohexyl, respectively, lost activity. We
also evaluated cyclic tertiary amides (85−88) and found that
piperidine analogue 85’s activity was attenuated with ∼50−
65% inhibition at the highest concentration tested. The
placement of distal heteroatoms (N and O) in morpholine
86 and N-Me-piperazine 88 maintained good potency, while
NH-piperazine 87 was sevenfold more potent in mIDH1
R132H inhibition compared to analogue 70. Importantly,
piperazine 87 also was more stable in a single point rat liver
Our earlier SAR study of the bicyclic dihydroquinoline-
dione core in hit molecule 1 had revealed that most changes
reduced potency, but lactam 10 maintained a similar activity
against the R132H IDH1 mutant (Table 1). This observation
provided an attractive opportunity to both substitute the amide
and open the ring to reveal new opportunities for SAR
exploration in the northwestern region of the chemotype. To
that end, we evaluated the ring-opened variants of the lactam,
as shown in Table 5; this was done with the symmetrical 2,6-
diethylphenyl substituent at the R1 position from lead 66. This
was a strategic decision as we realized that the possibility of
restricted rotation around N-R1 could lead to atropisomers
(vide infra), adding one more variable to our SAR analysis.
Compared to ketone 66, ester (67 and 69) and acid (68)
variants lost much, if not all mIDH1 target potency. However,
amide 70 only experienced a small drop in R132H activity and
did not show >75% inhibition at 38 μM against R132C (Table
5). This analogue proved pivotal in providing an additional
SAR handle for a new amide-substituted pyridone series.
With only moderate variations to our initial multicomponent
coupling, we were able to develop a modular synthesis tolerant
of significant modification to both the amide and the
pyridinone substituents (Scheme 2). The initial condensation
between keto ester Ia and N,N-dimethylformamide (DMF)
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Table 7. Pyridinone 6-Position SAR
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled mIDH1 R132H and R132C assays. IC50 is reported for compounds
with >75% inhibition at 38 μM, the highest concentration tested.
Table 8. In Vitro Drug-like Properties of Analogues with >10-fold Increase in R132C mIDH1 Potency over Compound 87
microsomal stability assay (70: t1/2 = 1.5 min; 87: t1/2 > 30
min).36 Additionally, 87 had better aqueous kinetic solubility
than methyl amide 70 (70: [M] < 1 μM; 87: [M] = 6.7 μM).
These results led us to maintain this substitution while we
examined the SAR of the pyridinone 6-substituent.
and cyclopropylmethyl 93 had benchmark potencies with IC50
< 100 nM for both IDH1 mutants. The replacement of the
methyl group on the n-propyl side chain in 89 with an
electron-donating methoxy (94) or electron-withdrawing
trifluoromethyl group (95) led to a comparative reduction in
potency. Within cyclic ethers, the racemic tetrahydrofuran
(THF) 96 was more potent than the larger tetrahydropyran
97. Analogous pyrrolidine 98 (racemic) proved to be much
less potent with IC50 ∼ 10 μM. We postulated that perhaps,
steric congestion to this region of the pharmacophore helps
position the piperazine away from R3 (as suggestively drawn in
Our evaluation of the pyridinone 6-substituent R3 is
presented in Table 7. The n-propyl analogue 89 was ∼3-fold
more potent toward R132H mIDH1 but with a marked 15-fold
improvement toward mR132C. While this trend did not carry
to the α-branched isopropyl 90, it emerged again with
analogues 91−93 with β-branching. Indeed, isobutylene 92
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Table 9. Piperazine SAR
a
b
IC50 values were determined utilizing the diaphorase- and resazurin-coupled mIDH1 R132H and R132C assays. Compounds showed >97%
c
inhibition at 38 μM, the highest concentration tested. Compounds showed >85% inhibition at 38 μM, the highest concentration tested.
d
Compounds are racemic.
Table 7); we suspect that the amide is also not coplanar to the
pyridine pi-system. It could be that such a conformation is
more desirable toward R132C activity and results in the >10-
fold increase in potency observed in analogues 89, 91−93, and
96 compared to the methyl analogue 87. We assessed in vitro
drug-like properties in this set (Table 8); isobutylene 92 had a
desirable balance between potency, rat liver microsome
stability, and permeability. Thus, it was held at the R3 position
for further SAR studies. We also noticed that all compounds
had low aqueous kinetic solubility.
(PAMPA), rat and mouse microsome stability, and solubility]
nor in vivo PK profiles (data not shown). Another noteworthy
observation was that the analogues described in Tables 7−10
were at least 1000-fold selective for mIDH1s over WT IDH1.
Finally, our SAR studies shifted back to the pyridinone 1-
arene (Table 10). Analogous to our earlier studies, an ortho
substituent proved essential. The complete removal of all
substituents in 113 led to a 7.5-fold drop in R132H potency
and a more significant 55-fold drop in R132C potency. The
presence of one ortho ethyl in 114 was 1−3-fold less potent
compared to its diethyl counterpart 92. While the combination
of ethyl,methyl-di-ortho substitutions in 115 led to a potency
drop, especially toward the R132C mutant, the ethyl-chloro
combination in 116 was equipotent to 92. Keeping the ortho-
ethyl group constant, we shifted to the meta position (R10) and
found that methyl 117, methoxy 118, and chloro 119
maintained their potency across both mutants. While it was
apparent that steric congestion around the pyridone seemed
critical for activity, we anticipated that hindered rotation
around the pyridone N-aryl bond likely led to the existence of
atropisomers that could have dissimilar activities. As two
representative examples, we separated the atropisomers in 118
and 119 and discovered that they had a ∼3- and 3−8-fold
Upon optimizing the R3 substituent, the NR4R5 site (see
VIII in Scheme 2) was further explored (Table 9). A subset of
analogues with diverse groups at the piperazine 3-position such
as methyl 99, ethyl 101, propyl 102, cyclopropyl 103,
hydroxymethyl 104, ketone 105, trifluoromethyl 106, cyano
107, acid 108, and amide 109 maintained their potency against
both IDH mutants, showcasing that electron-donating and
-withdrawing groups were tolerated at this position. The 2-
methyl piperazine 100 was also potent. Furthermore, hetero-
bicyclic systems also produced analogues 110−112 with
nanomolar activity. Although these substitutions were tolerated
for enzymatic inhibition, these additions typically did not
provide additional benefits with respect to their in vitro drug-
like properties [parallel artificial membrane permeability assay
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Table 10. SAR at the Pyridinone N1-Aryl Ring
biochemical
IDH1 R132H
IDH1 R132C
a
a
compd
92
113
R9
R10
R11
IC50 (μM) SD
IC50 (μM) SD
Et
H
H
H
Et
H
0.044 0.003
0.33 0.00
0.058 0.010
3.2 0.6
114
115
116
117
Et
Et
Et
Et
Et
H
H
H
Me
OMe
H
0.056 0.004
0.27 0.00
0.044 0.003
0.044 0.003
0.114 0.007
0.12 0.02
0.16 0.01
2.2 0.2
Me
Cl
H
0.055 0.004
0.11 0.02
0.075 0.000
0.13 0.03
0.67 0.04
0.10 0.01
0.072 0.005
0.54 0.10
0.063 0.015
118
H
(+)-118
(−)-118
119
(+)-119
(−)-119
AG-120
0.42 0.05
Et
Cl
H
0.114 0.007
0.081 0.005
0.25 0.04
NCATS-SM5637, NSC 791985
0.065 0.009
a
IC50 values were determined utilizing the diaphorase- and resazurin-coupled R132H and R132C mIDH1 assays. All compounds showed >80%
inhibition at 38 μM, the highest concentration tested.
Table 11. 2-HG Levels (% of Vehicle Control) in U87-mIDH1 (R132H) Cells after 48 h Incubation with the Compound
Compared to DMSO and Drug-like Properties
a
b
% 2-HG
IDH1 R132H
single point
PAMPA
solubility
compd
91
92
99
100
103
105
108
111
112
118
(−)-119
(+)-119
100 nM
500 nM
IC50 (μM) SD
RLM (t1/2, min)
(10−6 cm/s)
(μg/mL)
33 25
13 3.1
11 5.5
14 5.1
17 3.8
23 4.2
29 16
11 3.1
32 8.4
40 1.7
ND
12 6.4
16 1.1
0.11 0.01
0.044 0.003
0.044 0.003
0.039 0.003
0.078 0.005
0.035 0.002
0.055 0.004
0.094 0.000
0.062 0.004
0.114 0.007
0.25 0.04
17
14
25
17
12
2
23
>30
9
16
<1
<1
<1
<1
<1
<1
16
<1
<1
<1
<1
225
213
40
48
275
<1
89
99
549
255
434
8
2.3
11 5.3
14 0.81
13 3.1
10 8.6
10 3.4
18 2.8
19 3.7
ND
>30
>30
>30
5.9 0.16
4.1 0.17
0.081 0.005
<1
a
b
Values represent % 2-HG after 48 h incubation with an inhibitor, where 100% is normalized to 2-HG levels in the DMSO-treated control. The
enzymatic R132H IC50 has been reintroduced in the table to visualize the entire data set for all compounds in this table. ND: Not Determined.
difference in the R132H and R132C biochemical potencies,
respectively.
biochemical IC50s toward R132H mIDH1 were similar (114
and 81 nM). Notably, in this cellular assay, (+)-119 appears
100 times more potent (<0.7 nM) than in the biochemical
enzyme inhibition assay and more potent than AG-120 which
had a comparable biochemical potency.
For the compounds in Table 11, an analysis of drug-like
properties using our in-house high throughput assays showed
that analogues 111, 118, (−)-119, and (+)-119 had promising
stability in rat liver microsomes with t1/2 > 30 min, high passive
permeability, and low aqueous kinetic solubility. From this
subset, based on its potent cellular activity, we chose (+)-119
to showcase the chemical series in PK/PD studies.
Having developed several biochemically potent mIDH1
inhibitors, for a representative set of compounds, we next
assessed cellular activity in U87 cells, a cell line of glioblastoma
origin engineered to express the IDH1 R132H mutation.
Inhibition of 2-HG production, secreted from cells into media,
was measured by mass spectrometry 48 h after the addition of
compounds at 100 and 500 nM (Table 11). Analogue (+)-119
lowered 2-HG levels by more than 94% at 100 nM. Dose−
response curves for atropisomer (+)-119, the corresponding
unseparated mixture of atropisomers 119, and the approved
drug AG-120 are shown in Figure 2. (+)-119 was more potent
at reducing 2-HG levels than 119, even though their
To directly assess target engagement in cells, we used a high-
throughput CETSA platform that uses a split NanoLuciferase
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lactone hydrolysis and in situ elimination of the tertiary alcohol
provided the sensitive intermediate VIIc. We observed
proximity-promoted deleterious cyclization back to lactone
VIIb under a variety of neutralization conditions as well during
the subsequent amide coupling. Careful neutralization with
acetic acid to neutral pH and subsequent removal via wash
steps was necessary following lactone hydrolysis. The amide
bond formation also had to adhere to a strict order of addition
of HATU, iPr2NEt, and then the Boc-protected piperazine to
furnish VIIIa in 95% yield. Subsequently, separation of
atropisomers proved optimal at the stage of the protected
piperazine VIIIa with the use of a CHIRAL OD-H column.
Final deprotection, which necessitated short reaction times
with a significant excess (35 equiv) of trifluoroacetic acid in
order to minimize relactonization, followed by neutralization of
the TFA salt by aqueous sodium bicarbonate provided the
pure atropisomer (+)-119. The stereochemical configuration
of the atropisomer was proved by X-ray analysis of a single
crystal of the intermediate VIIb (Supporting Information) that
was formed during attempts to form a HCl salt of (+)-119
(NCATS-SM5637, NSC 791985).
Figure 2. Dose-dependent reduction of 2-HG in U87-mIDH1
(R132H) cells (N = 3).
A single dose of 30 mg/kg (+)-119 administered orally to
CD1 mice led to good exposure in the plasma with a Cmax
∼3.34 μM and AUClast of 24,371 h·ng/g. It also crossed the
blood brain barrier with an AUC of 6996 h·ng/g and a brain/
plasma ratio of 28% (Figure 4).
(SplitNanoLuc) reporter to detect soluble protein in cells.37
After tagging the 15-amino acid sequence 86b from NanoLuc
to the C-terminus of R132H mIDH1 (termed IDH1(R132H)-
86b) and transient expression in HEK293T cells, soluble
protein was measured by complementation of the larger 11S
fragment to 86b. This reconstitutes NanoLuciferase activity
and allows its quantification using the substrate furimazine.
Dose−response testing measured the ability of compounds to
increase the thermal stability of IDH1(R132H)-86b when cells
were heated to 56 °C for 3.5 min. (+)-119 and AG-120 were
equipotent in this assay, whereas the corresponding mixture
119 had a 10-fold greater EC50 (Figure 3).
We devised a scalable route to (+)-119 and related
analogues to enable in vivo testing (Scheme 3). Commencing
with a similar multicomponent coupling with dicarbonyl 6,6-
dimethyldihydro-2H-pyran-2,4(3H)-dione Ic, a multicompo-
nent coupling reaction efficiently assembled VIIb which upon
We compared the activities of (+)-119 and AG-120 in vivo,
using the U87 mIDH1 (R132H) xenograft to assess PK/PD
responses (Figure 5). After a single 30 mg/kg p.o. dose, AG-
120 reached a higher plasma Cmax than (+)-119 but after 8 h,
(+)-119 displayed higher plasma concentrations. Similarly, 4 h
after dosing, concentrations of (+)-119 in tumor were higher
than AG-120. (+)-119 had very slow clearance from tumor
with sustained average concentrations of 9.5, 7.2, and 6.8 μM
at 24, 36, and 48 h, respectively, compared to 1.6, 1.4, and 0.77
μM for AG-120. These higher sustained tumoral concen-
trations of (+)-119 appear to be responsible for the greater
reduction in tumor 2-HG, as compared to AG-120, from the
16 h time point onward. If this promising activity translates to
the clinical setting, it could provide a therapeutic advantage
over AG-120 (see the Supporting Information for profiling
data on (+)-119).
CONCLUSIONS
■
An extended medicinal chemistry campaign starting with a 7,8-
dihydro-2H-1λ2-quinoline-2,5(6H)-dione chemotype led to
the discovery of new amide-substituted pyridones as potent
R132H and R132C mIDH1 inhibitors. The lead compound
119 had nanomolar activities against both IDH1 mutants and
lowered the mIDH1-catalyzed product 2-HG in cells. The
single atropisomer (+)-119 (NCATS-SM5637, NSC 791985)
was shown to engage mIDH1 in cells and reduce 2-HG
production more potently that 119 (13-fold in HEK293
engagement assay and 30-fold in U87 2-HG assay). In a PK/
PD model, after a single oral dose at 30 mg/kg, (+)-119
showed sustained tumor concentrations (7 μM after 48 h) and
greater reduction in 2-HG levels at later time points (16−48 h)
than the approved mIDH1 drug AG-120. Further head-to-head
comparative animal studies in various mIDH1-driven cancer
models with key compounds from this chemical series, such as
NCATS-SM5637 (NSC 791985), and AG-120 are ongoing
and will be reported in due course.
Figure 3. Dose-dependent stabilization of NanoLuc-tagged R132H
mIDH1 in HEK293 cells (N = 3).
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Scheme 3. (A) Synthesis of Isobutylene Analogue (+)-119 Including Separation of Atropisomers; (B) Formation of VIIb from
(+)-119 and Its X-ray Coordinates of Its Single Crystal
Figure 4. PK parameters and conc vs time profiles in brain and plasma of CD1 mice (n = 3) after a single 30 mpk oral dose of (+)-119 formulated
as a solution in 20% PEG300, 40% of Solutol solution (30% w/w in water), and 40% DI water.
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Figure 5. PK/PD in a U87 R132H mIDH-based xenograft mouse model: (A) Concentrations of (+)-119 or AG-120 in plasma and tumor after
administration of a single 30 mpk PO dose. (B) Concentrations of 2-HG in tumor.
mL penicillin, and 100 μg/mL streptomycin. 8000 cells/well/100 μL
EXPERIMENTAL SECTION
■
were seeded into clear, tissue culture-treated 96-well plates (Corning)
Materials and Methods: Biology. mIDH1-R132H and mIDH-
in 100 μL culture medium excluding wells along the edge (which
R132C Enzyme Assay. Pubchem AID 624002. Enzyme buffer was
instead were filled with culture medium only) and incubated
dispensed into black, solid 1536-well plates at 3 μL/well in 20 mM
overnight at 37 °C, 5% CO2, 90% RH. Culture medium was aspirated
Tris buffer, pH 7.5, containing final concentrations of 10 mM MgCl2,
and replaced with 100 μL of culture medium containing either a
20 mM NaCl, 0.001% Tween 20, 0.05% BSA, 2 mM β-ME, and 5.2
vehicle (DMSO) or mIDH1 inhibitor. Assays were established with
nM IDH1 R132H. Then, 23 nL of compounds or DMSO was
an inhibitor tested at two concentrations 500 and 100 nM or as seven-
delivered to each well using a pin tool. The inherent compound
point dose response. After 48 h, 75 μL of the culture medium was
fluorescence was measured at this point at 590 nm on a ViewLux plate
collected and snap-frozen on dry ice. Samples were analyzed by LC−
reader (Ex 525, Em 598, bodipy filter); this is test for assay
MS for 2-HG concentrations using Rapidfire/Mass Spectrometry
interference as we measure resorufin (em 590 nm in the end). The
(Quintara). Remaining cells were assessed for viability by adding 100
substrate buffer (3 μL; 20 mM Tris buffer, pH 7.5, containing final
concentrations of 10 mM MgCl2, 20 mM NaCl, 0.001% Tween 20,
0.05% BSA, 0.008 mM NADPH, and 1 mM α-ketoglutarate) was
added to start the enzymatic reaction, and the plate was briefly spun at
μL of fresh media and 50 μL of CellTiter-Glo reagent (Promega).
Luminescence was read using a ViewLux High-throughput CCD
imager (PerkinElmer).
SplitLuc CETSA. The mIDH1(R132H) open reading frame was
270g. After the reaction was allowed to progress for 80 min at room
cloned into a pcDNA3.1(+) backbone using the NheI and EcoRI
temperature, the remaining NADPH was detected with the
restriction sites. A 15 amino acid tag (86b, Gly-Ser-HiBiT-Gly-Ser)
diaphorase/resazurin-coupled system. A total of 3 μL of detection
buffer (20 mM Tris buffer, pH 7.5, containing final concentrations of
10 mM MgCl2, 20 mM NaCl, 0.001% Tween 20, 0.05% BSA, 0.53
μM diaphorase and 0.012 mM resazurin) was added, and after 5 min,
was fused in-frame to the carboxy terminus. HEK293T cells (obtained
from ATCC; CRL-1573) were cultured in DMEM (4.5 g/L glucose)
with 10% fetal bovine serum, 6 mM L-glutamine, 1 mM sodium
pyruvate, 50 U/mL penicillin, and 50 μg/mL streptomycin. Cells were
the fluorescence at 590 nm was measured on an Envision plate reader
grown at 37 °C in a humidified incubator maintained at 5% CO2.
Cells were transfected in T75 flasks using a reverse transfection
procedure, where 9 mL of complexes (45 μL Lipofectamine 2000 and
22.5 μg DNA) was combined with 10 mL of HEK293T cell
suspension (1 × 106 cells/mL, 10 million cells total). After 24 h, cells
were harvested by trypsinization, resuspended at 1 × 106 cells/mL
(DPBS with CaCl2 and MgCl2 plus 1 g/L glucose), and dispensed (15
μL cells/well) into 384-well PCR plates (Roche) using a Multidrop
Combi (Thermo Fisher). Compounds (63 nL) or DMSO vehicle
control (63 nL) were subsequently pinned using a pin tool (GNF)
and incubated for 1 h at 37 °C. Plates were sealed and heated at 56 °C
for 3.5 min and cooled to 25 °C using an AB qPCR machine (Roche)
with a ramp speed of 1.5 °C/s for the heating phase and max ramp
rate for the cooling phase. Three microliters of 6% NP40 was added
per well and incubated for 30 min to allow cell lysis followed by the
addition of 11S (purified from Escherichia coli) and furimazine
(Promega) substrate (at final concentrations of 100 nM and 0.5×,
respectively). Samples were analyzed for luminescence intensity using
a ViewLux reader.
(Ex 544, Em 590, bodipy filter, 10 flashes). The % activity was
determined from the corrected fluorescence values. The activity was
normalized with 5.2 nM R132H IDH1 (no inhibitor) as 0% inhibition
and the activity with no enzyme as 100% inhibition.
We also measured for assay interference by measuring dose-
dependent activity against the diaphorase/resazurin-coupled system
by repeating the assay mentioned above in the absence of mIDH1.
This will flag false positives that may inhibit the NADPH to NADP+
conversion.
Concentration−response curves were fitted to the signals arising
from the resulting fluorescence. The concentration−response curves
were then classified based on curve quality (r2), response magnitude,
and degree of measured activity, and compounds were subsequently
categorized based on their curve class. Active inhibitors showed
concentration-dependent increases in fluorescence, concordant with a
decrease in IDH1 R132H activity and less substrate NADPH
utilization. Inactive compounds showed no effect on the fluorescence
signal relative to the DMSO control.
Cellular 2-HG Production Assay. 2-HG secreted from cells was
quantified as previously described with modifications. U87-R132H
cells were cultured in Dulbecco’s modified Eagle medium (DMEM)
high glucose with glutamine supplemented with 10% FBS, 100 units/
Kinetic Solubility Assay. Pion’s patented μSOL assay was used for
kinetic solubility determination. In this assay, the classical saturation
shake-flask solubility method was adapted as previously described.38
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Test compounds were prepared in 10 mM DMSO stock and diluted
to a final drug concentration of 150 μM in the aqueous solution (pH
7.4, 100 mM phosphate buffer). Samples were incubated at room
temperature for 6 h and vacuum-filtered using Tecan Te-Vac to
remove any precipitates. The concentration of the compound in the
filtrate was measured via UV absorbance (λ: 250−498 nm). The
unknown drug concentration was determined by comparing the fully
solubilized reference plate which contained 17 μM of the compound
dissolved in spectroscopically pure n-propanol. All compounds were
tested in duplicates. The kinetic solubility (μg/mL) of compounds
was calculated using the μSOL Evolution software. The three controls
used were albendazole (low solubility), phenazolpyridine (moderate
solubility), and furosemide (high solubility).39
Rat Liver Microsome Stability Assay. Single time point micro-
somal stability was determined in a 96-well HTS format. Sample
preparation was automated using a Tecan EVO 200 robot. A high-
resolution LC/MS (Thermo Q Exactive) instrument was used to
measure the percentage of compound remaining after incubation
using a previously described method.40 Six standard controls were
tested in each run: buspirone and propranolol (for short half-life),
loperamide and diclofenac (for short to medium half-life), and
carbamazepine and antipyrine (for long half-life). 10 mM DMSO
stock solutions of the drugs were first diluted to 10 μM in 1:2 MeCN/
DI H2O and then further diluted to 1 μM in assay buffer. Briefly, the
incubate consisted of 0.5 mg/mL microsomal protein, 1.0 μM drug
concentration, and NADPH regeneration system (containing 0.650
mM NADP+, 1.65 mM glucose 6-phosphate, 1.65 mM MgCl2, and 0.2
unit/mL G6PDH) in 100 mM phosphate buffer at pH 7.4. The
incubation was carried out at 37 °C for 15 min.36 The reaction was
quenched by adding 555 μL of acetonitrile (∼1:2 ratio) containing
0.28 μM albendazole (internal standard). Sample acquisition and data
analysis were done using a previously described method.40
Parallel Artificial Membrane Permeability Assay. The stirring
double-sink PAMPA method (patented by pION Inc.) was employed
to determine the permeability of compounds via PAMPA as published
before.41 The PAMPA lipid membrane consisted of an artificial
membrane of a proprietary lipid mixture and dodecane (pION Inc.),
optimized to predict gastrointestinal tract passive permeability. The
lipid was immobilized on a plastic matrix of a 96-well “donor” filter
plate placed below a 96-well “acceptor” plate. pH 7.4 solution was
used in both donor and acceptor wells. The test articles, stocked in 10
mM DMSO solutions, were diluted to 0.05 mM in aqueous buffer
(pH 7.4), and the concentration of DMSO was 0.5% in the final
solution. During the 30 min permeation period at room temperature,
the test samples in the donor compartment were stirred using the
Gutbox Technology (pION Inc.) to reduce the aqueous boundary
layer. The test article concentrations in the donor and acceptor
compartments were measured using a UV plate reader (Nano Quant,
calculated for plasma and brain: Tmax, Cmax, and AUC24h. Animals were
also monitored during the in-life phase by once daily cageside
observations; no adverse clinical signs were noted as part of the PK
report.
PK/PD. A PK/PD study was performed in 6-week old female
athymic nude mice (nu/nu NCr). Mice were housed in microisolator
cages with food and water provided ad libitum. All work was
performed on an approved Institutional Animal Care and Use
Committee protocol in AAALACi accredited facilities with automated
12 on−12 off light cycles. Mice were implanted subcutaneously with
the U87MG human glioblastoma cell line (1 × 107 cells/mouse),
containing the IDH1 R132H mutation. On the day of tumor staging
(∼200 mg), mice were randomized into 3 groups of 32 mice each.
These groups were treated with a single oral dose of either vehicle
(10% NMP, 40% PEG300, 25% [30% Solutol in water], 25%
deionized water), compound (+)-119 at 30 mg/kg, or AG120 at 30
mg/kg. Mice were anesthetized with isoflurane by inhalation and the
tumors and K2EDTA anticoagulated blood were collected from
cohorts of 4 mice per group at 1, 2, 4, 8, 16, 24, 36, and 48 h post
dose. Plasma was obtained by centrifugation and all samples were
flash-frozen until analysis. (+)-119 and AG120 in plasma and tumor
tissue and 2-HG in tumor were quantified using validated LC−MS/
MS methods.
Use of Animal Subjects. All animal studies included as part of this
manuscript were performed in accordance with institutional guide-
lines as defined by Institutional Animal Care and Use Committee
(IACUC).
EXPERIMENTAL SECTION CHEMISTRY
■
General Methods for Chemistry. All air- or moisture-sensitive
reactions were performed under positive pressure of nitrogen with
oven-dried glassware. Anhydrous solvents or reagents such as
dichloromethane, DMF, acetonitrile, methanol, and triethylamine
were purchased from Sigma-Aldrich. To follow most chemical
reactions, LC/MS of reaction aliquots was analyzed using a gradient
of 4−100% acetonitrile (containing 0.025% trifluoroacetic acid) and
water (containing 0.05% trifluoroacetic acid) with a 4.5 min run time
at a flow rate of 1 mL/min in an Agilent Extend-C18 column (3.5 μm,
4.6 × 100 mm) at a temperature of 50 °C using an Agilent diode array
detector. Confirmation of molecular formulae was accomplished using
electrospray ionization in the positive mode with the Agilent
Masshunter software (version B.02).
Preparative purification was performed on a Waters semi-
preparative HPLC system. The column used was a Phenomenex
Luna C18 (5 μm, 30 × 75 mm) at a flow rate of 45 mL/min. The
mobile phase consisted of acetonitrile and water (each containing
0.1% trifluoroacetic acid). A gradient of 10−50% acetonitrile over 8
min was used during the purification. Fraction collection was
triggered by UV detection (220 nM). This purification method is
referred to as Standard Acidic Gradient Method.
Purity of all final compounds was ≥95% as determined on an
Agilent LC/MS (Agilent Technologies, Santa Clara, CA) using a 7
min gradient of 4−100% acetonitrile (containing 0.025% trifluoro-
acetic acid) and water (containing 0.05% trifluoroacetic acid) with an
8 min run time at a flow rate of 1 mL/min. A Phenomenex Luna C18
column (3 μm, 3 × 75 mm) was used at a temperature of 50 °C using
an Agilent diode array detector. Mass determination was performed
using an Agilent 6130 mass spectrometer with electrospray ionization
in the positive mode.
̈
Infinite 200 PRO, Tecan Inc., Mannedorf, Switzerland). Permeability
calculations were performed using pION Inc. software and were
expressed in units of 10−6 cm/s. Compounds with a low or weak UV
signal were analyzed using high-resolution LC/MS (Thermo
QExactive). The three controls used were ranitidine (low
permeability), dexamethasone (moderate permeability), and verapa-
mil (high permeability).
Mouse PK Studies. Studies were conducted by Pharmaron. Fed
male CD1 mice (sourced from Si Bei Fu LaboratoryAnimal
Technology Co. Ltd.), approximately 6−8 weeks of age and weight
of approximately 25−30 g, were dosed with (+)-119 at 30 mpk dose
PO. The formulation was a solution at 3 mg/mL in 20% PEG300,
40% of Solutol solution (30% w/w in water), and 40% DI water. This
was prepared prior to dosing a cohort of N = 24 mice. Plasma and
whole brain were collected from N = 3 mice at 15 min, 30 min, 1 h, 2
h, 4 h, 6 h, 84, and 24 h postdose. Approximately, 0.200 mL of blood
was collected via the heart puncture at each time point. Blood samples
were then transferred into plastic microcentrifuge tubes containing
heparin−Na as an anticoagulant. Samples were then centrifuged at
4000g for 5 min at 4 °C to obtain plasma. Plasma samples were then
stored in polypropylene tubes, quickly frozen, and kept at −75 °C
until analyzed by LC/MS/MS. The following PK parameters were
1H NMR spectra were recorded on Varian 400 MHz
spectrometers. Chemical shifts are reported in ppm with a
nondeuterated solvent (DMSO-h6 at 2.50 ppm) as an internal
standard for DMSO-d6 solutions. High-resolution mass spectra
(HRMS) were recorded on an Agilent 6210 Time-of-Flight LC/MS
system.
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Synthetic Procedures. Synthesis of Nitrile Intermediates
(Scheme 1, Intermediate IV).
EtOH and AcOH. The reaction mixture was concentrated under a
stream of air, and 2-(6-chlorobenzo[d]thiazol-2-yl)acetonitrile was
used without further purification.
Method 1: 2-(4-(4-Chlorophenyl)thiazol-2-yl)acetonitrile (N1 or
IVa in Schemes 2 and 3). To a solution of 2-bromo-1-(4-
chlorophenyl)ethanone (2.33 g, 10 mmol) in ethanol (25 mL) was
added 2-cyanoethanethioamide (1 g, 10 mmol). The reaction mixture
was heated at reflux for 15.5 h. The reaction mixture was cooled to 0
°C. A precipitate formed and was removed by filtration, washed with
hexanes, and subsequently dried under vacuum. The product, 2-(4-(4-
chlorophenyl)thiazol-2-yl)acetonitrile is a brown powder; LCMS: m/
z (M + H)+ = 235.0; 1H NMR (400 MHz, CDCl3): δ 7.88−7.77 (m,
2H), 7.48 (s, 1H), 7.44−7.35 (m, 2H), 4.17 (s, 2H).
2-(5-Chlorobenzo[d]thiazol-2-yl)acetonitrile (N6, Intermediate
for Compound 14). 2-(5-Chlorobenzo[d]thiazol-2-yl)acetonitrile
(N6, intermediate for compound 14) was prepared according to
Method 4, however refluxing was conducted overnight followed by
heating in a microwave at 120 °C for 1 h and at 150 °C for 1 h. The
reaction mixture was concentrated under a stream of air, and 2-(5-
chlorobenzo[d]thiazol-2-yl)acetonitrile was used without further
purification; LCMS: m/z (M + H)+ = 209.0.
2-(4-Phenylthiazol-2-yl)acetonitrile (N2, Intermediate for Com-
pound 11). Synthesized by Method 1 substituting 2-bromo-1-
phenylethanone as a starting material. Following the reaction, the
mixture was concentrated and purified via silica gel chromatography
(0−30% EtOAc/hexanes). The product is a red-orange solid (1.53 g,
77%); LCMS: m/z (M + H)+ = 201.1.
Method 5: 2-(1-(4-Chlorophenyl)-1H-imidazol-4-yl)acetonitrile
(N7, Intermediate for Compound 15). A mixture of 2-(1H-
imidazol-4-yl)acetonitrile (150 mg, 1.4 mmol), 1-chloro-4-iodoben-
zene (467 mg, 1.96 mmol), 4,7-dimethoxy-1,10-phenanthroline (101
mg, 0.42 mmol), copper(I) oxide (20 mg, 0.14 mmol), cesium
carbonate (776 mg, 2.38 mmol), PEG (250 mg), and DMSO (1.5
mL) was heated with stirring at 110 °C for 24 h. The reaction mixture
was diluted with water, 0.1 N HCl, and EtOAc and extracted (2×).
The organic layers were combined, dried with magnesium sulfate,
concentrated, and purified via reverse-phase chromatography (C18)
(5−100% acetonitrile/water [0.1% TFA]) to afford 2-(1-(4-
chlorophenyl)-1H-imidazol-4-yl)acetonitrile (35 mg, 12%) as a yellow
oil; LCMS: m/z (M + H)+ = 218.0.
Method 2: 2-(4′-Chloro-[1,1′-biphenyl]-3-yl)acetonitrile (N3,
Intermediate for Compound 23). In a microwave vial, 2-(3-
bromophenyl)acetonitrile (300 mg, 1.53 mmol), (4-chlorophenyl)-
boronic acid (287 mg, 1.84 mmol), tetrakis(triphenylphosphine)-
palladium(0) (88 mg, 0.077 mmol), 2 M aqueous sodium carbonate
solution (2.3 mL), and dimethoxyethane (10 mL) were combined.
The reaction mixture was heated in a microwave with stirring at 140
°C for 1 h. The reaction mixture was diluted with water and extracted
with CH2Cl2 (2 × 10 mL); the organic layers were combined, dried
with magnesium sulfate, concentrated, and purified via silica gel
chromatography (0−25% EtOAc/hexanes) to afford 2-(4′-chloro-
[1,1′-biphenyl]-3-yl)acetonitrile (298 mg, 86%); 1H NMR (400
MHz, CDCl3): δ 7.62−7.38 (m, 7H), 7.37−7.28 (m, 1H), 3.82 (t, J =
0.7 Hz, 2H).
Method 6: (2-(1-Phenyl-1H)-pyrazol-3-yl)acetonitrile (N8, Inter-
mediate for Compound 19). A mixture of copper(II) acetate (382
mg, 2.1 mmol), 2-(1H-pyrazol-3-yl)acetonitrile (150 mg, 1.4 mmol),
phenylboronic acid (341 mg, 2.8 mmol), triethylamine (0.390 mL, 2.8
mmol), pyridine (0.227 mL, 2.8 mmol), 4 Å molecular sieves (500
mg), and dichloromethane (10 mL) was heated at 55 °C overnight.
The reaction mixture was filtered, extracted (DCM/1 N HCl), dried
with magnesium sulfate, and concentrated, and 2-(1-phenyl-1H)-
pyrazol-3-yl)acetonitrile was used without further purification;
LCMS: m/z (M + H)+ = 184.1.
2-(6-(4-Chlorophenyl)pyridin-2-yl)acetonitrile (N4, Intermediate
for Compound 25). Method 3: 2-(6-Bromopyridin-2-yl)acetonitrile:
A solution of n-butyllithium in hexanes (1.6 M, 17.4 mL, 27.9 mmol)
was added slowly to a solution of acetonitrile (1.5 mL, 28.7 mmol) in
THF (40 mL) at −78 °C. A precipitate formed. The slurry was stirred
at this temperature for 30 min. A solution of 2,6-dibromopyridine (2
g, 8.4 mmol) in THF (10 mL) was added slowly to the slurry. The
reaction mixture was stirred at −78 °C for 45 min. The mixture was
allowed to warm slowly to rt over 30 min. The reaction mixture was
diluted with water and extracted with EtOAc (2 × 10 mL); the
organic layers were combined, dried with magnesium sulfate,
concentrated, and purified via silica gel chromatography (0−40%
EtOAc/hexanes) to afford 2-(6-bromopyridin-2-yl)acetonitrile (1.65
g, 99%) as a yellow oil that solidified upon cooling; LCMS: m/z (M +
H)+ = 197.0. Method 2 was used to afford 2-(6-(4-chlorophenyl)-
pyridin-2-yl)acetonitrile N4; LCMS: m/z (M + H)+ = 229.1.
Method 7: 2-(2-Phenyl-1H-imidazol-5-yl)acetonitrile. A mixture
of 5-(chloromethyl)-2-phenyl-1H-imidazole hydrochloride (197 mg,
0.86 mmol) and sodium cyanide (127 mg, 2.58 mmol) in DMSO (3
mL) was stirred at rt overnight. The reaction mixture was diluted with
water and saturated aqueous sodium bicarbonate solution, extracted
(EtOAc × 2), dried with magnesium sulfate, and concentrated, and 2-
(2-phenyl-1H-imidazol-5-yl)acetonitrile was used without further
purification.
Method 8: tert-Butyl 5-(Cyanomethyl)-2-phenyl-1H-imidazole-1-
carboxylate (N9, Intermediate for Compound 17). A mixture of 2-
(2-phenyl-1H-imidazol-5-yl)acetonitrile (50 mg, 0.27 mmol), Boc2O
(0.070 mL, 0.3 mmol), and DMAP (trace) in acetonitrile (3 mL) and
sodium cyanide (127 mg, 2.58 mmol) in DMSO (3 mL) was stirred at
rt for 40 min and concentrated under a stream of air. tert-Butyl 5-
(cyanomethyl)-2-phenyl-1H-imidazole-1-carboxylate was used with-
out further purification; LCMS: m/z (M + H)+ = 284.1 (weak).
Method 4: 2-(6-Chlorobenzo[d]thiazol-2-yl)acetonitrile (N5,
Intermediate for Compound 13). Malononitrile (65 mg, 0.98
mmol) and 2-amino-5-chlorobenzenethiol (157 mg, 0.98 mmol)
were heated at 50 °C for 4 h and at reflux for 1 h in a mixture of
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3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-
pyridin-2(1H)-one (2). Step 1: 2-Oxo-1,2-dihydropyridine-3-carbo-
thioamide: Ammonium sulfide (0.509 mL, 2.99 mmol) was added to
a solution of 2-oxo-1,2-dihydropyridine-3-carbonitrile (211 mg, 1.757
mmol) in methanol (14 mL). The reaction mixture was heated in a
microwave at 130 °C for 2 h. The mixture stood overnight at rt and
crystals formed. The mixture was further cooled to 0 °C for 4 h. The
methanol was poured off and the solid was triturated with methanol
and used as is in the following step. 1H NMR (400 MHz, DMSO-d6):
δ 12.60 (s, 1H), 11.31 (s, 1H), 9.98 (s, 1H), 8.93 (dd, J = 7.4, 2.2 Hz,
1H), 7.77 (dd, J = 6.2, 2.3 Hz, 1H), 6.52 (dd, J = 7.4, 6.2 Hz, 1H).
Step 2: 3-(4-(4-Chlorophenyl)thiazol-2-yl)pyridin-2(1H)-one: To
2-oxo-1,2-dihydropyridine-3-carbothioamide (124 mg, 0.804 mmol)
in ethanol (2 mL) was added 2-bromo-1-(4-chlorophenyl)ethanone
(188 mg, 0.804 mmol). The reaction mixture was heated at reflux for
17.5 h. The reaction mixture was cooled to rt and diluted with
hexanes. The solid was removed by filtration, washed with hexanes,
and dried on high vacuum. The product (213 mg, 65%) is a red-
Method 9: 2-(4-Phenyl-1H-imidazol-1-yl)acetonitrile (N10, Inter-
mediate for Compound 16). A mixture of 4-phenyl-1H-imidazole
(250 mg, 1.7 mmol), chloroacetonitrile (0.22 mL, 3.5 mmol), and
potassium carbonate (1.2 g, 8.7 mmol) in DMF (8 mL) was stirred at
rt for 22 h. The reaction mixture was diluted with water, extracted
(EtOAc × 2), dried with magnesium sulfate, and concentrated to
afford 2-(4-phenyl-1H-imidazol-1-yl)acetonitrile as a brown solid
which was used without further purification; LCMS: m/z (M + H)+ =
184.1.
1
brown powder. H NMR (400 MHz, DMSO-d6): δ 12.10 (s, 1H),
2-(3-Phenyl-1H-pyrazol-1-yl)acetonitrile (N11, Intermediate for
Compound 20). 2-(3-Phenyl-1H-pyrazol-1-yl)acetonitrile (N11,
intermediate for compound 20) was synthesized by Method 9;
LCMS: m/z (M + H)+ = 184.1 (weak).
8.28 (dd, J = 7.2, 2.1 Hz, 1H), 7.80 (s, 1H), 7.76−7.68 (m, 2H), 7.30
(s, 1H), 7.20−7.11 (m, 2H), 6.15 (dd, J = 7.2, 6.3 Hz, 1H).
Step 3: 3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-
dimethoxyphenyl)pyridin-2(1H)-one (Table 1; compound 2): To a
mixture of 3-(4-(4-chlorophenyl)thiazol-2-yl)pyridin-2(1H)-one (60
mg, 0.208 mmol), copper(II) acetate (56.6 mg, 0.312 mmol), and 2,5-
dimethoxyphenylboronic acid (76 mg, 0.416 mmol) were added 1,4-
dioxane (2 mL) and pyridine (0.2 mL). The reaction mixture was
sealed and heated at 80 °C for 60 h. The mixture was filtered with
thiol resin, washed with EtOAc, and concentrated. The crude mixture
was diluted with DMSO and purified by reverse-phase chromatog-
raphy (Standard Acidic Gradient Method) to afford as a TFA salt, 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione. LCMS: m/z (M +
H)+ = 425.1; 1H NMR (400 MHz, DMSO-d6): δ 8.70 (dd, J = 7.3, 2.0
Hz, 1H), 8.16 (s, 1H), 8.07 (d, J = 8.6 Hz, 2H), 7.78 (dd, J = 6.6, 2.0
Hz, 1H), 7.51 (d, J = 8.6 Hz, 2H), 7.17 (dd, J = 8.5, 1.3 Hz, 1H),
7.10−7.02 (m, 2H), 6.59 (t, J = 6.9 Hz, 1H), 3.73 (s, 3H), 3.68 (s,
3H); HRMS (ESI): m/z (M + H)+ calcd for C22H18ClN2O3S,
425.0721; found, 425.0723. Retention time = 3.787 min.
2-(4-Phenyl-1H-pyrazol-1-yl)acetonitrile (N12, Intermediate for
Compound 21). 2-(4-Phenyl-1H-pyrazol-1-yl)acetonitrile (N12,
intermediate for compound 21) was synthesized by Method 9;
LCMS: m/z (M + H)+ = 184.1 (weak).
Method 10: 3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (1).
Step 1: In a vial, 5,5-dimethylcyclohexane-1,3-dione (0.100 g, 0.713
mmol) and DMF-DMA (0.096 mL, 0.713 mmol) were mixed and
stirred well (no solvent) for 5 min. The reaction mixture became
yellow oil.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-6-
methylpyridin-2(1H)-one (3).
Step 2: To the mixture were added i-PrOH (2.55 mL), 2-(4-(4-
chlorophenyl)thiazol-2-yl)acetonitrile (167 mg, 0.713 mmol), and
piperidine (0.071 mL, 0.713 mmol). The reaction mixture was
allowed to stir at rt for 3 h. The solid turned into solution. After 3 h, a
precipitate formed at which point the solvent was removed by blowing
down under a stream of air with mild heating at 30 °C.
Step 1: 2-(4-(4-Chlorophenyl)thiazol-2-yl)-N-(2,5-
dimethoxyphenyl)acetamide: To a mixture of 2-(4-(4-chlorophenyl)-
thiazol-2-yl)acetic acid (155 mg, 0.611 mmol) in CH2Cl2 (3 mL)
were added HATU (348 mg, 0.916 mmol), DIPEA (320 μL, 1.833
mmol), and 2,5-dimethoxyaniline (103 mg, 0.672 mmol). The
reaction mixture was stirred for 1 h at room temperature. The
reaction mixture was diluted with water and CH2Cl2 and extracted (2
× 15 mL); the organic layers were combined, dried with magnesium
sulfate, concentrated, and purified via silica gel chromatography to
afford 2-(4-(4-chlorophenyl)thiazol-2-yl)-N-(2,5-dimethoxyphenyl)-
acetamide as a solid; LCMS: m/z (M + H)+ = 389.
Step 3: To the resulting residue were added acetic acid (1 mL) and
2,5-dimethoxyaniline (109 mg, 0.713 mmol). The reaction mixture
was stirred for 15 min at rt, a precipitate formed almost immediately.
The solvent was removed by blowing down under a stream of air with
mild heating at 30 °C. The crude mixture was diluted with DMSO
and purified by reverse-phase chromatography (Standard Acidic
Gradient Method) to afford as a TFA salt, 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydroqui-
1
noline-2,5(1H,6H)-dione LCMS: m/z (M + H)+ = 521.1; H NMR
(400 MHz, DMSO-d6): δ 9.04 (s, 1H), 8.22 (s, 1H), 8.12−8.05 (m,
2H), 7.58−7.50 (m, 2H), 7.23 (d, J = 9.2 Hz, 1H), 7.13 (dd, J = 9.1,
3.1 Hz, 1H), 7.05 (d, J = 3.0 Hz, 1H), 3.75 (s, 3H), 3.71 (s, 3H), 2.62
(d, J = 17.7 Hz, 1H), 2.46 (d, J = 2.9 Hz, 2H), 2.22 (d, J = 17.7 Hz,
1H), 0.99 (s, 3H), 0.94 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd
for C28H26ClN2O4S, 521.1296; found, 521.1321. Retention time =
3.858 min.
Step 2: 3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphen-
yl)-6-methylpyridin-2(1H)-one (Table 1; Compound 3): A mixture
of 2-(4-(4-chlorophenyl)thiazol-2-yl)-N-(2,5-dimethoxyphenyl)-
acetamide (74 mg, 0.190 mmol), (E)-4-methoxybut-3-en-2-one
(38.8 μL, 0.381 mmol), and potassium 2-methylpropan-2-olate
(21.35 mg, 0.190 mmol) was heated at 80 °C for 3.5 h. The reaction
mixture was diluted with methanol/CH2Cl2/water and to alleviate the
emulsion, it is acidified with 1 N HCl, extracted with EtOAc, and
concentrated. The crude mixture was diluted with DMSO and
purified by reverse-phase chromatography (Standard Acidic Gra-
dient Method) to afford as a TFA salt, 3-(4-(4-chlorophenyl)thiazol-
2-yl)-1-(2,5-dimethoxyphenyl)-6-methylpyridin-2(1H)-one. LCMS:
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m/z (M + H)+ = 521.1; 1H NMR (400 MHz, DMSO-d6): δ 8.61 (d, J
= 7.4 Hz, 1H), 8.15−8.03 (m, 3H), 7.55−7.47 (m, 2H), 7.18 (d, J =
9.1 Hz, 1H), 7.07 (dd, J = 9.1, 3.1 Hz, 1H), 6.98 (d, J = 3.1 Hz, 1H),
6.59 (dd, J = 7.5, 0.9 Hz, 1H), 3.74 (s, 3H), 3.69 (s, 3H), 2.03 (d, J =
0.8 Hz, 3H); HRMS (ESI): m/z (M + H)+ calcd for C23H20ClN2O3S,
439.0878; found, 439.0897. Retention time = 3.822 min.
(ESI): m/z (M + H)+ calcd for C26H22ClN2O4S, 493.0983; found,
493.0973. Retention time = 3.741 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-6,7-
dihydro-1H-cyclopenta[b]pyridine-2,5-dione (7). This compound
was prepared using Method 10 using cyclopentane-1,3-dione in step 1
to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphen-
yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS:
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-5,6,7,8-tetrahydroquinolin-2(1H)-one (4). To a solution of
3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (35 mg, 0.067 mmol)
compound 1 in THF (2 mL) was added lithium aluminum hydride
(0.101 mL, 0.101 mmol). The reaction mixture was stirred at rt for 1
h and then heated at 60 °C for 12 h. The reaction mixture was cooled
to 0 °C and quenched with methanol and a bit of water, diluted with
EtOAc, and extracted (2 × 25 mL); the organic layers were
combined, dried with magnesium sulfate, and concentrated. The
crude mixture was diluted with DMSO and purified by reverse-phase
chromatography (Standard Acidic Gradient Method) to afford as a
TFA salt, 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphen-
yl)-7,7-dimethyl-5,6,7,8-tetrahydroquinolin-2(1H)-one. LCMS: m/z
(M + H)+ = 507.2; 1H NMR (400 MHz, DMSO-d6): δ 8.48 (s, 1H),
8.13−8.00 (m, 3H), 7.54−7.45 (m, 2H), 7.16 (d, J = 9.1 Hz, 1H),
7.05 (dd, J = 9.1, 3.0 Hz, 1H), 6.87 (d, J = 3.0 Hz, 1H), 3.73 (d, J =
1.4 Hz, 3H), 3.66 (s, 3H), 2.73 (t, J = 6.5 Hz, 2H), 2.09 (d, J = 17.8
Hz, 1H), 1.78 (d, J = 17.8 Hz, 1H), 1.47 (t, J = 6.7 Hz, 2H), 0.88 (s,
3H), 0.84 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C28H28ClN2O3S, 507.1504; found, 507.1509. Retention time = 4.196
min.
1
m/z (M + H)+ = 479.1; H NMR (400 MHz, DMSO-d6): δ 8.77 (s,
1H), 8.27 (s, 1H), 8.14 (d, J = 8.61 Hz, 2H), 7.54 (d, J = 8.61 Hz,
2H), 7.27 (d, J = 9.00 Hz, 1H), 7.07−7.22 (m, 2H), 3.76 (d, J = 12.91
Hz, 5H), 2.77−2.92 (m, 1H), 2.55−2.77 (m, 3H); HRMS (ESI): m/z
(M + H)+ calcd for C25H20ClN2O4S, 479.0827; found, 479.0840.
Retention time = 3.672 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-5-
hydroxyquinolin-2(1H)-one (8). To a solution of 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,8-dihydroqui-
noline-2,5(1H,6H)-dione (25 mg, 0.051 mmol) compound 6 in 1,4-
dioxane (3 mL) was added DDQ (17.27 mg, 0.076 mmol). The
reaction mixture was stirred at 70 °C for 12 h. The organic solvent
was concentrated. The crude mixture was diluted with DMSO and
purified by reverse-phase chromatography (Standard Acidic Gra-
dient Method) to afford as a TFA salt, 3-(4-(4-chlorophenyl)thiazol-
2-yl)-1-(2,5-dimethoxyphenyl)-5-hydroxyquinolin-2(1H)-one.
LCMS: m/z (M + H)+ = 491.2; HRMS (ESI): m/z (M + H)+ calcd
for C26H20ClN2O4S, 491.0827; found, 491.0817. Retention time =
3.619 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,8-
dihydro-1,7-naphthyridine-2,5(1H,6H)-dione (9). This compound
was prepared using Method 10 using tert-butyl 3,5-dioxopiperidine-1-
carboxylate in step 1 followed by Boc deprotection after step 3 using
TFA to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxy-
phenyl)-7,8-dihydro-1,7-naphthyridine-2,5(1H,6H)-dione as a TFA
1
salt. LCMS: m/z (M + H)+ = 494.1; H NMR (400 MHz, DMSO-
d6): δ 9.03 (s, 1H), 8.30 (s, 1H), 8.14−8.07 (m, 2H), 7.59−7.52 (m,
2H), 7.29 (d, J = 9.2 Hz, 1H), 7.19 (dd, J = 9.2, 3.1 Hz, 1H), 7.06 (d,
J = 3.1 Hz, 1H), 3.98−3.79 (m, 2H), 3.76 (s, 3H), 3.74 (s, 3H);
HRMS (ESI): m/z (M + 2H)2+ calcd for C25H22ClN3O4S, 493.0821;
found, 493.0863. Retention time = 3.148 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinolin-2(1H)-one (5). Step 1: To a solution
of 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (200 mg, 0.384
mmol) compound 1 in EtOH (10 mL) was added sodium
borohydride (29.0 mg, 0.768 mmol). Gas evolution was observed.
The reaction mixture was stirred at 50 °C for 12 h. The reaction
mixture was cooled to rt, diluted with water and EtOAc, and extracted
(2 × 25 mL); the organic layers were combined, dried with
magnesium sulfate, and concentrated. The crude mixture was taken to
the next step without further purification.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,8-
dihydro-1,6-naphthyridine-2,5(1H,6H)-dione (10). This compound
was prepared using Method 10 using tert-butyl 2,4-dioxopiperidine-1-
carboxylate in step 1 followed by Boc deprotection using TFA to
afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-
7,8-dihydro-1,6-naphthyridine-2,5(1H,6H)-dione as a TFA salt.
1
LCMS: m/z (M + H)+ = 494.2; H NMR (400 MHz, DMSO-d6):
δ 9.06 (s, 1H), 8.20 (s, 1H), 8.13−8.04 (m, 2H), 7.92 (s, 1H), 7.57−
7.47 (m, 2H), 7.21 (dd, J = 8.8, 0.8 Hz, 1H), 7.15−7.06 (m, 2H), 3.74
(s, 3H), 3.71 (s, 3H), 3.42−3.30 (m, 2H), 2.73−2.60 (m, 1H), 2.40
(dt, J = 17.6, 6.5 Hz, 1H); HRMS (ESI): m/z (M + Na)+ calcd for
C25H20ClN3NaO4S, 516.0755; found, 516.0768. Retention time =
3.822 min.
Step 2: To a solution of 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-
dimethoxyphenyl)-5-hydroxy-7,7-dimethyl-5,6,7,8-tetrahydroquino-
lin-2(1H)-one (38 mg, 0.073 mmol) in 1,4-dioxane (10 mL) was
added pTSA (1.38 mg, 0.1 equiv). The reaction mixture was stirred at
rt for 4 h. The organic solvent was concentrated. The crude mixture
was diluted with DMSO and purified by reverse-phase chromatog-
raphy (Standard Acidic Gradient Method) to afford as a TFA salt, 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-di-
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(4-phenylthiazol-2-yl)-
7,8-dihydroquinoline-2,5(1H,6H)-dione (11). This compound was
prepared using Method 10 using 2-(4-phenylthiazol-2-yl)acetonitrile
N2 in step 2 to afford 1-(2,5-dimethoxyphenyl)-7,7-dimethyl-3-(4-
phenylthiazol-2-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA
methyl-7,8-dihydroquinolin-2(1H)-one. LCMS: m/z (M + H)+
=
1
505.2; H NMR (400 MHz, DMSO-d6): δ 8.60 (s, 2H), 8.01−8.23
(m, 6H), 7.54 (m, 2H), 7.18 (d, J = 8.61 Hz, 3H), 7.18−7.30 (m,
2H), 7.06−7.18 (m, 2H), 7.00 (d, J = 3.13 Hz, 2H), 6.47 (d, J = 9.78
Hz, 2H), 5.63 (d, J = 9.78 Hz, 1H), 3.73 (d, J = 19.96 Hz, 7H), 2.37−
2.48 (m, 2H), 2.14 (s, 1H), 0.84−1.14 (m, 7H); HRMS (ESI): m/z
(M + H)+ calcd for C28H26ClN2O3S, 505.1347; found, 505.1351.
Retention time = 4.152 min.
1
salt. LCMS: m/z (M + H)+ = 487.2; H NMR (400 MHz, DMSO-
d6): δ 9.14 (s, 1H), 8.25 (s, 1H), 8.18−8.11 (m, 2H), 7.57 (dd, J =
8.3, 7.0 Hz, 2H), 7.50−7.41 (m, 1H), 7.33 (d, J = 9.1 Hz, 1H), 7.23
(dd, J = 9.1, 3.1 Hz, 1H), 7.14 (d, J = 3.0 Hz, 1H), 3.85 (s, 3H), 3.81
(s, 3H), 2.72 (d, J = 17.8 Hz, 1H), 2.64−2.49 (m, 2H), 2.31 (d, J =
17.7 Hz, 1H), 1.09 (s, 3H), 1.03 (s, 3H); HRMS (ESI): m/z (M +
Na)+ calcd for C28H26N2NaO4S, 509.1505; found, 509.1529.
Retention time = 3.718 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,8-
dihydroquinoline-2,5(1H,6H)-dione (6). This compound was pre-
pared using Method 10 using cyclohexane-1,3-dione in step 1 to
afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-
7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z
3-(5-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (12). This com-
pound was prepared using Method 10 using 2-(5-(4-chlorophenyl)-
thiazol-2-yl)acetonitrile in step 2 to afford 3-(5-(4-chlorophenyl)-
thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydroqui-
1
(M + H)+ = 493; H NMR (400 MHz, DMSO-d6): δ 9.04 (s, 1H),
8.21 (d, J = 1.2 Hz, 1H), 8.11−8.02 (m, 2H), 7.57−7.46 (m, 2H),
7.21 (d, J = 9.1 Hz, 1H), 7.14−7.02 (m, 2H), 3.74 (d, J = 1.1 Hz,
3H), 3.70 (s, 3H), 2.51 (d, J = 1.2 Hz, 2H), 2.47 (m, 4H); HRMS
noline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+
=
4930
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1
521.2; H NMR (400 MHz, DMSO-d6): δ 9.03 (d, J = 4.7 Hz, 1H),
(ESI): m/z (M + H)+ calcd for C28H28N3O4, 470.2074; found,
8.49 (s, 1H), 7.84−7.75 (m, 2H), 7.64−7.54 (m, 2H), 7.32 (d, J = 9.2
Hz, 1H), 7.26−7.17 (m, 1H), 7.13 (d, J = 3.1 Hz, 1H), 3.84 (s, 3H),
3.79 (s, 3H), 2.71 (d, J = 17.7 Hz, 1H), 2.54 (d, J = 3.1 Hz, 2H), 2.30
(d, J = 17.8 Hz, 1H), 1.08 (s, 3H), 1.02 (s, 3H); HRMS (ESI): m/z
(M + H)+ calcd for C26H24ClN2O4S, 495.114; found, 495.1159.
Retention time = 3.787 min.
470.2054. Retention time = 2.59 min.
3-(6-Chlorobenzo[d]thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (13). This com-
pound was prepared using Method 10 using 2-(6-chlorobenzo[d]-
thiazol-2-yl)acetonitrile N5 in step 2 to afford 3-(6-chlorobenzo[d]-
thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydroqui-
noline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+
=
1
495.1; H NMR (400 MHz, DMSO-d6): δ 9.14 (s, 1H), 8.27 (d, J =
2.1 Hz, 1H), 8.08 (d, J = 8.7 Hz, 1H), 7.56 (dd, J = 8.7, 2.2 Hz, 1H),
7.25 (d, J = 9.1 Hz, 1H), 7.18−7.05 (m, 2H), 3.75 (s, 3H), 3.72 (s,
3H), 2.64−2.60 (m, 2H), 2.35−2.17 (m, 2H), 1.00 (s, 3H), 0.94 (s,
3H); HRMS (ESI): m/z (M + H)+ calcd for C26H24ClN2O4S,
495.114; found, 495.1138. Retention time = 3.795 min.
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-2,5-dioxo-1,2,5,6,7,8-
hexahydro-quinoline-3-carbonitrile dione (18). Step 1: Similar to
Method 10; Step 2: Similar to Method 10 with stirring only for 1 h.
Also, aniline was added prior to concentration; Step 3: Acetic acid was
added and stirred overnight at rt. The reaction mixture was diluted
with water and DCM and extracted (2×); the organic layers were
combined, dried with magnesium sulfate, concentrated, and purified
via silica gel chromatography (10−100% EtOAc/hexanes) to afford 1-
(2,5-dimethoxyphenyl)-7,7-dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydro-
quinoline-3-carbonitrile (70% on 2.85 mmol scale); LCMS: m/z (M
+ H)+ = 353.1. Step 4: 1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-2,5-
dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carboximidamide: To a mix-
ture of 1-(2,5-dimethoxyphenyl)-7,7-dimethyl-2,5-dioxo-1,2,5,6,7,8-
hexahydroquinoline-3-carbonitrile (60 mg, 0.170 mmol) in MeOH
(1 mL) was added sodium methanolate (398 μL, 1.703 mmol) in
MeOH. The reaction mixture was stirred at 45 °C for 45 min and
then ammonia hydrochloride (91 mg, 1.703 mmol) and AcOH (1.5
mL) were added. The reaction mixture was stirred at 60 °C for 12 h.
The reaction mixture was diluted with water and DCM and extracted
(2×); the organic layers were combined, dried with magnesium
sulfate, concentrated, and purified via silica gel chromatography (10−
100% EtOAc/hexanes) to afford 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carboximida-
mide; LCMS: m/z (M + H)+ = 370.1. Step 5: To a mixture of 1-(2,5-
dimethoxyphenyl)-7,7-dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydroqui-
noline-3-carboximidamide (50 mg, 0.135 mmol) in THF (1 mL) were
added 2-bromo-1-(4-chlorophenyl)ethan-1-one (135 μL, 0.135
mmol) and sodium bicarbonate (11.37 mg, 0.135 mmol). The
reaction mixture was stirred at 70 °C for 2 h and then AcOH (7.75
μL, 0.135 mmol) was added. The reaction mixture was stirred at 70
°C for 2 h. The solvent was removed by blowing down under a stream
of air with mild heating at 30 °C. The crude mixture was diluted with
DMSO and purified by reverse-phase chromatography (Standard
Acidic Gradient Method) to afford as a TFA salt, 3-(5-(4-
chlorophenyl)-1H-imidazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione. LCMS: m/z (M +
3-(5-Chlorobenzo[d]thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (14). This com-
pound was prepared using Method 10 using 2-(5-chlorobenzo[d]-
thiazol-2-yl)acetonitrile N6 in step 2 to afford 3-(5-chlorobenzo[d]-
thiazol-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydroqui-
noline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+
=
1
495.1; H NMR (400 MHz, DMSO-d6): δ 9.15 (s, 1H), 8.20−8.12
(m, 2H), 7.46 (dd, J = 8.5, 2.0 Hz, 1H), 7.25 (d, J = 9.1 Hz, 1H),
7.18−7.05 (m, 2H), 3.75 (s, 3H), 3.72 (s, 3H), 2.64 (d, J = 17.8 Hz,
1H), 2.24 (d, J = 17.8 Hz, 1H), 1.00 (s, 3H), 0.94 (s, 3H); HRMS
(ESI): m/z (M + Na)+ calcd for C28H25ClN2NaO4S, 543.1116; found,
543.113. Retention time = 3.811 min.
3-(1-(4-Chlorophenyl)-1H-imidazol-4-yl)-1-(2,5-dimethoxyphen-
yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (15). This
compound was prepared using Method 10 using 2-(1-(4-chloro-
phenyl)-1H-imidazol-4-yl)acetonitrile N7 in step 2 to afford 3-(1-(4-
chlorophenyl)-1H-imidazol-4-yl)-1-(2,5-dimethoxyphenyl)-7,7-di-
methyl-7,8-dihydro-quinoline-2,5(1H,6H)-dione as a TFA salt.
1
LCMS: m/z (M + H)+ = 504.1; H NMR (400 MHz, DMSO-d6):
δ 8.65 (s, 1H), 8.38 (d, J = 1.4 Hz, 1H), 8.20 (d, J = 1.4 Hz, 1H),
7.75−7.62 (m, 2H), 7.59−7.48 (m, 1H), 7.18 (d, J = 9.1 Hz, 1H),
7.07 (dd, J = 9.1, 3.0 Hz, 1H), 6.94 (d, J = 3.0 Hz, 1H), 3.72 (s, 3H),
3.67 (s, 3H), 2.63 (dd, J = 3.7, 1.9 Hz, 1H), 2.38 (d, J = 8.1 Hz, 1H),
2.31−2.26 (m, 1H), 0.96 (s, 3H), 0.91 (s, 3H); HRMS (ESI): m/z
(M + H)+ calcd for C28H27ClN3O4, 504.1685; found, 504.1678.
Retention time = 3.343 min.
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(4-phenyl-1H-imida-
zol-1-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (16). This com-
pound was prepared using Method 10 using 2-(4-phenyl-1H-
imidazol-1-yl)acetonitrile N10 in step 2 to afford 1-(2,5-dimethox-
yphenyl)-7,7-dimethyl-3-(4-phenyl-1H-imidazol-1-yl)-7,8-dihydroqui-
1
H)+ = 504.1; H NMR (400 MHz, DMSO-d6): δ 8.78 (s, 1H), 7.88
noline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+
=
(d, J = 8.2 Hz, 2H), 7.63 (s, 1H), 7.38 (d, J = 8.5 Hz, 2H), 7.20 (d, J =
9.2 Hz, 1H), 7.15−6.95 (m, 2H), 3.71 (d, J = 13.8 Hz, 6H), 2.66−
2.54 (m, 2H), 2.42 (d, J = 4.5 Hz, 2H), 0.98 (s, 3H), 0.92 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C28H27ClN3O4, 504.1685;
found, 504.1709. Retention time = 3.171 min.
470.2; 1H NMR (400 MHz, DMSO-d6): δ 8.71 (s, 1H), 8.35 (s, 1H),
8.27 (s, 1H), 7.88−7.80 (m, 2H), 7.41 (dd, J = 8.3, 7.1 Hz, 2H),
7.33−7.19 (m, 2H), 7.12 (dd, J = 9.1, 3.1 Hz, 1H), 7.02 (d, J = 3.1
Hz, 1H), 3.74 (s, 3H), 3.73 (s, 3H), 2.60 (d, J = 17.6 Hz, 1H), 2.44
(d, J = 4.1 Hz, 2H), 2.19 (d, J = 17.5 Hz, 1H), 0.99 (s, 3H), 0.94 (s,
3H); HRMS (ESI): m/z (M + H)+ calcd for C28H28N3O4, 470.2074;
found, 470.2095. Retention time = 3.02 min.
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(1-phenyl-1H-pyrazol-
3-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (19). This compound
was prepared using Method 10 using 2-(1-phenyl-1H-pyrazol-3-
yl)acetonitrile N8 in step 2 to afford 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-3-(1-phenyl-1H-pyrazol-3-yl)-7,8-dihydroquinoline-2,5-
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(2-phenyl-1H-imida-
zol-4-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (17). This com-
pound was prepared using Method 10 using tert-butyl 5-
(cyanomethyl)-2-phenyl-1H-imidazole-1-carboxylate N9 in step 2
followed by treatment with TFA to afford 1-(2,5-dimethoxyphenyl)-
7,7-dimethyl-3-(2-phenyl-1H-imidazol-4-yl)-7,8-dihydroquinoline-
2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ = 470.2; 1H
NMR (400 MHz, DMSO-d6): δ 8.71 (s, 1H), 8.01 (d, J = 7.6 Hz,
2H), 7.45 (d, J = 31.3 Hz, 3H), 7.18 (d, J = 9.1 Hz, 1H), 7.08 (dd, J =
9.1, 3.0 Hz, 2H), 6.94 (d, J = 3.0 Hz, 1H), 3.73 (s, 3H), 3.68 (s, 3H),
2.66−2.55 (m, 1H), 2.40 (d, J = 8.2 Hz, 1H), 2.29 (p, J = 1.9 Hz,
1H), 2.13 (d, J = 17.5 Hz, 1H), 0.97 (s, 3H), 0.92 (s, 3H); HRMS
1
(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ = 470.2; H
NMR (400 MHz, DMSO-d6): δ 8.68 (s, 1H), 8.51 (d, J = 2.5 Hz,
1H), 7.94−7.86 (m, 2H), 7.56−7.47 (m, 2H), 7.37−7.28 (m, 1H),
7.20 (d, J = 9.1 Hz, 1H), 7.16−7.05 (m, 2H), 6.98 (d, J = 3.0 Hz,
1H), 3.75 (s, 3H), 3.71 (s, 3H), 2.56 (d, J = 17.6 Hz, 1H), 2.41 (d, J =
7.3 Hz, 2H), 2.14 (d, J = 17.6 Hz, 1H), 0.98 (s, 3H), 0.93 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C28H28N3O4, 470.2074; found,
470.2094. Retention time = 3.539 min.
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(3-phenyl-1H-pyrazol-
1-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (20). This compound
4931
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Article
was prepared using Method 10 using 2-(3-phenyl-1H-pyrazol-1-
yl)acetonitrile N11 in step 2 to afford 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-3-(3-phenyl-1H-pyrazol-1-yl)-7,8-dihydroquinoline-2,5-
(dd, J = 11.1, 6.7 Hz, 2H), 7.19 (d, J = 8.9 Hz, 2H), 7.08 (d, J = 9.4
Hz, 1H), 7.01−6.93 (m, 1H), 6.47 (s, 0H), 3.73 (s, 3H), 3.69 (s, 3H),
2.51 (s, 3H), 2.14 (d, J = 17.8 Hz, 1H), 0.97 (s, 3H), 0.92 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C28H28N3O4, 470.2074; found,
470.2073. Retention time = 3.428 min.
1
(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ = 470.2; H
NMR (400 MHz, DMSO-d6): δ 8.64 (d, J = 2.6 Hz, 1H), 8.51 (s,
1H), 7.96−7.88 (m, 2H), 7.50−7.41 (m, 2H), 7.41−7.32 (m, 1H),
7.22 (d, J = 9.1 Hz, 1H), 7.12 (dd, J = 9.1, 3.1 Hz, 1H), 7.04 (d, J =
3.0 Hz, 1H), 6.96 (d, J = 2.6 Hz, 1H), 3.75 (s, 3H), 3.72 (s, 3H), 2.57
(d, J = 17.5 Hz, 1H), 2.44 (d, J = 4.2 Hz, 2H), 2.16 (d, J = 17.6 Hz,
1H), 0.99 (s, 3H), 0.94 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd
for C28H28N3O4, 470.2074; found, 470.2074. Retention time = 3.66
min.
3-(4′-Chloro-[1,1′-biphenyl]-3-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (23). This com-
pound was prepared using Method 10 using 2-(4′-chloro-[1,1′-
biphenyl]-3-yl)acetonitrile N3 in step 2 to afford 3-(4′-chloro-[1,1′-
biphenyl]-3-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydro-
quinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ =
1
514.2; H NMR (400 MHz, DMSO-d6): δ 8.12 (s, 1H), 7.99−7.93
(m, 1H), 7.79−7.60 (m, 4H), 7.56−7.45 (m, 3H), 7.19 (d, J = 9.1 Hz,
1H), 7.08 (dd, J = 9.1, 3.1 Hz, 1H), 6.97 (d, J = 3.0 Hz, 1H), 3.74 (s,
3H), 3.71 (s, 3H), 2.97 (s, 3H), 2.60−2.49 (m, 1H), 2.47−2.32 (m,
2H), 2.14 (d, J = 17.5 Hz, 1H), 0.98 (s, 3H), 0.94 (s, 3H); HRMS
(ESI): m/z (M + H)+ calcd for C31H29ClNO4, 514.178; found,
514.1777. Retention time = 3.835 min.
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(4-phenyl-1H-pyrazol-
1-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (21). This compound
was prepared using Method 10 using 2-(4-phenyl-1H-pyrazol-1-
yl)acetonitrile N12 in step 2 to afford 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-3-(4-phenyl-1H-pyrazol-1-yl)-7,8-dihydroquinoline-2,5-
1
(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ = 470.2; H
NMR (400 MHz, DMSO-d6): δ 8.95 (d, J = 0.8 Hz, 1H), 8.44 (s,
1H), 8.25 (d, J = 0.8 Hz, 1H), 7.67−7.59 (m, 2H), 7.41−7.31 (m,
2H), 7.26−7.16 (m, 2H), 7.12 (dd, J = 9.1, 3.1 Hz, 1H), 7.04 (d, J =
3.1 Hz, 1H), 3.75 (s, 3H), 3.72 (s, 3H), 2.62−2.50 (m, 1H), 2.43 (d, J
= 4.1 Hz, 2H), 2.17 (d, J = 17.6 Hz, 1H), 0.99 (s, 3H), 0.94 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C28H28N3O4, 470.2074; found,
470.208. Retention time = 3.608 min.
3-([1,1′-Biphenyl]-4-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-
7,8-dihydroquinoline-2,5(1H,6H)-dione (24). This compound was
prepared using Method 10 using 2-([1,1′-biphenyl]-4-yl)acetonitrile
in step 2 to afford 3-([1,1′-biphenyl]-4-yl)-1-(2,5-dimethoxyphenyl)-
7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt.
1
LCMS: m/z (M + H)+ = 480.2; H NMR (400 MHz, DMSO-d6): δ
8.09 (s, 1H), 7.83−7.75 (m, 2H), 7.74−7.65 (m, 4H), 7.51−7.42 (m,
2H), 7.40−7.31 (m, 1H), 7.20 (d, J = 9.2 Hz, 1H), 7.08 (dd, J = 9.1,
3.1 Hz, 1H), 6.98 (d, J = 3.0 Hz, 1H), 3.74 (s, 3H), 3.72 (s, 3H),
2.45−2.33 (m, 2H), 2.14−2.10 (m, 2H), 0.99 (s, 3H), 0.94 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C31H30NO4, 480.2169; found,
480.2176. Retention time = 3.719 min.
3-(6-(4-Chlorophenyl)pyridin-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (25). This com-
pound was prepared using Method 10 using 2-(6-(4-chlorophenyl)-
pyridin-2-yl)acetonitrile N4 in step 2 to afford 3-(6-(4-chlorophenyl)-
pyridin-2-yl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydroqui-
1-(2,5-Dimethoxyphenyl)-7,7-dimethyl-3-(5-phenyl-1H-pyrazol-
3-yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (22). Step 1: A mixture
of 1-(2,5-dimethoxyphenyl)-7,7-dimethyl-2,5-dioxo-1,2,5,6,7,8-hexa-
hydroquinoline-3-carbonitrile (60 mg, 0.17 mmol) (intermediate
after step 3 in the synthesis of compound 18) in concentrated HCl (3
mL) was heated at 80 °C for 22 h. The reaction mixture was diluted
with water, extracted (DCM/MeOH × 3), dried with magnesium
sulfate, and concentrated to afford 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carboxylic acid
which was used without further purification; LCMS: m/z (M + H)+
= 372.1. Step 2: To the acid (28 mg, 0.075 mmol) in DCM (3 mL)
were added a drop of DMF and oxalyl chloride (0.033 mL, 0.38
mmol). The reaction mixture was stirred at rt for 1.2 h. The reaction
mixture was concentrated under a stream of argon, rediluted with
DCM, and reconcentrated to afford 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carbonyl chlor-
ide; this was verified by LCMS that showed the formation of the
methyl ester on the addition of MeOH to an aliquot from the
reaction.
noline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+
=
515.1; 1H NMR (400 MHz, DMSO-d6): δ 8.94 (s, 1H), 8.27 (dd, J =
7.2, 1.6 Hz, 1H), 8.16 (d, J = 8.6 Hz, 2H), 7.95−7.85 (m, 2H), 7.59
(d, J = 8.6 Hz, 2H), 7.19 (d, J = 9.1 Hz, 1H), 7.08 (dd, J = 9.1, 3.0 Hz,
1H), 6.99 (d, J = 3.0 Hz, 1H), 3.73 (s, 3H), 3.70 (s, 3H), 2.58 (d, J =
17.6 Hz, 1H), 2.41 (d, J = 7.2 Hz, 2H), 2.15 (d, J = 17.6 Hz, 1H),
0.98 (s, 3H), 0.93 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C30H28ClN2O4, 515.1732; found, 515.175. Retention time = 3.8 min.
N-(4-Chlorobenzyl)-1-(2,5-dimethoxyphenyl)-7,7-dimethyl-2,5-
dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carboxamide (26). This
compound was prepared using Method 10 using N-(4-chloroben-
zyl)-2-cyanoacetamide in step 2 to afford N-(4-chlorobenzyl)-1-(2,5-
dimethoxyphenyl)-7,7-dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydroqui-
noline-3-carboxamide as a TFA salt. LCMS: m/z (M + H)+ = 495.2;
1H NMR (400 MHz, DMSO-d6): δ 9.55 (t, J = 6.0 Hz, 1H), 8.79 (s,
Step 3: To a solution of acetophenone (0.026 mL, 0.23 mmol) in
THF (1 mL) that had been cooled to −78 °C was added a solution of
LiHMDS (1 M THF, 0.225 mL, 0.225 mmol) slowly. The reaction
mixture was continued to stir at this temperature for 1 h (faint yellow
solution) at which point a solution of 1-(2,5-dimethoxyphenyl)-7,7-
dimethyl-2,5-dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carbonyl chlor-
ide (VI) (0.075 mmol) in THF (1.5 mL) was added. The reaction
mixture became more yellow and was allowed to warm slowly for 1.5
h. The reaction mixture turned from yellow to red (likely red is
doubly deprotonated trione). Step 4: Hydrazine (3 equiv) in ethanol
was added and stirring resumed for 1 h. Acetic acid (3 drops) was
added, and the reaction mixture turned from red to yellow along with
the formation of a precipitate. The reaction mixture was heated at 50
°C for 1 h and stood at rt for 1 week. The crude mixture was diluted
with DMSO and purified by reverse-phase chromatography (Stand-
ard Acidic Gradient Method) to afford as a TFA salt, 1-(2,5-
dimethoxyphenyl)-7,7-dimethyl-3-(5-phenyl-1H-pyrazol-3-yl)-7,8-di-
hydroquinoline-2,5(1H,6H)-dione. LCMS: m/z (M + H)+ = 470.2;
1H NMR (400 MHz, DMSO-d6): δ 13.14 (s, 1H), 8.48 (s, 1H), 7.81
1H), 7.40−7.29 (m, 2H), 7.30 (d, J = 8.5 Hz, 2H), 7.19 (d, J = 9.1
Hz, 1H), 7.09 (dd, J = 9.1, 3.1 Hz, 1H), 6.99 (d, J = 3.0 Hz, 1H),
4.54−4.38 (m, 2H), 3.72 (s, 3H), 3.69 (s, 3H), 2.59 (d, J = 17.8 Hz,
1H), 2.42 (d, J = 2.2 Hz, 2H), 2.17 (d, J = 17.8 Hz, 1H), 0.96 (s, 3H),
0.90 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for C27H28ClN2O5,
495.1681; found, 495.1691. Retention time = 3.467 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-phenyl-7,8-di-
hydroquinoline-2,5 (1H,6H)-dione (27). This compound was
prepared using Method 10 using aniline in step 3 to afford N4-(4-
((1H-tetrazol-5-yl)methoxy)-3-chlorophenyl)-N6-([1,1′-biphenyl]-4-
yl)pyrimidine-4,6-diamine as a TFA salt. LCMS: m/z (M + H)+ =
1
461; H NMR (400 MHz, DMSO-d6): δ 9.06 (s, 1H), 8.22 (s, 1H),
8.13−8.05 (m, 2H), 7.67−7.51 (m, 5H), 7.47−7.40 (m, 2H), 2.45 (s,
2H), 2.42 (s, 2H), 0.96 (s, 6H); HRMS (ESI): m/z (M + H)+ calcd
for C26H22ClN2O2S, 461.1085; found, 461.1086. Retention time =
3.853 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-methoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (28). This com-
pound was prepared using Method 10 using 2-methoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-methoxy-
(d, J = 7.4 Hz, 1H), 7.74−7.66 (m, 1H), 7.45−7.31 (m, 1H), 7.27
4932
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Article
phenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
TFA salt. LCMS: m/z (M + H)+ = 491; 1H NMR (400 MHz,
DMSO-d6): δ 9.05 (s, 1H), 8.22 (s, 1H), 8.13−8.04 (m, 2H), 7.61−
7.49 (m, 3H), 7.37 (dd, J = 7.7, 1.6 Hz, 1H), 7.31 (dd, J = 8.5, 1.2 Hz,
1H), 7.17 (td, J = 7.6, 1.2 Hz, 1H), 3.77 (s, 3H), 2.61−2.51 (m, 2H),
2.250−2.20 (m, 2H), 0.98 (s, 3H), 0.94 (s, 3H); HRMS (ESI): m/z
(M + H)+ calcd for C27H24ClN2O3S, 491.1191; found, 491.1203.
Retention time = 3.86 min.
1-([1,1′-Biphenyl]-2-yl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (34). This com-
pound was prepared using Method 10 using [1,1′-biphenyl]-2-
amine in step 3 to afford 1-([1,1′-biphenyl]-2-yl)-3-(4-(4-
chlorophenyl)thiazol-2-yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5-
1
(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ = 537.2; H
NMR (400 MHz, DMSO-d6): δ 8.92 (s, 1H), 8.22 (s, 1H), 8.13−7.99
(m, 2H), 7.75−7.58 (m, 2H), 7.58−7.44 (m, 2H), 7.24 (qq, J = 7.1,
3.8, 3.0 Hz, 7H), 2.56 (d, J = 18.0 Hz, 1H), 2.40 (s, 1H), 2.18 (d, J =
16.2 Hz, 1H), 2.00 (d, J = 18.0 Hz, 1H), 0.91 (s, 3H), 0.48 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C32H26ClN2O2S, 537.139;
found, 537.1398. Retention time = 4.037 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-ethoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (29). This com-
pound was prepared using Method 10 using 2-ethoxyaniline in step
3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-ethoxyphenyl)-
7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-hydroxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (35). This com-
pound was prepared using Method 10 using 2-aminophenol in step
3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-hydroxyphenyl)-
7,7-dimethyl-7,8-dihydro-quinoline-2,5(1H,6H)-dione as a TFA salt.
1
LCMS: m/z (M + H)+ = 505.1; H NMR (400 MHz, DMSO-d6): δ
9.04 (s, 1H), 8.20 (s, 1H), 8.07 (d, J = 8.7 Hz, 2H), 7.57−7.48 (m,
3H), 7.34 (dd, J = 7.7, 1.7 Hz, 1H), 7.27 (d, J = 8.4 Hz, 1H), 7.14 (t, J
= 7.6 Hz, 1H), 4.06 (q, J = 6.9 Hz, 2H), 2.60 (d, J = 17.8 Hz, 1H),
2.50 (d, J = 16.2 Hz, 1H), 2.40 (d, J = 16.3 Hz, 1H), 2.16 (d, J = 17.7
Hz, 1H), 1.11 (t, J = 6.9 Hz, 3H), 0.97 (s, 3H), 0.93 (s, 3H); HRMS
(ESI): m/z (M + H)+ calcd for C28H26ClN2O3S, 505.1347; found,
505.1354. Retention time = 3.927 min.
1
LCMS: m/z (M + H)+ = 477.1; H NMR (400 MHz, DMSO-d6): δ
10.14 (s, 1H), 9.03 (s, 1H), 8.20 (s, 1H), 8.07 (d, J = 8.4 Hz, 2H),
7.52 (d, J = 8.3 Hz, 2H), 7.41−7.33 (m, 1H), 7.24 (dd, J = 7.9, 1.6
Hz, 1H), 7.07 (d, J = 8.2 Hz, 1H), 6.99 (t, J = 7.6 Hz, 1H), 2.57 (d, J
= 17.8 Hz, 1H), 2.45 (s, 2H), 2.29 (d, J = 17.7 Hz, 1H), 0.97 (s, 3H),
0.94 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for C26H22ClN2O3S,
477.1034; found, 477.1046. Retention time = 3.642 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-isopropoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (30). This com-
pound was prepared using Method 10 using 2-isopropoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-isopropox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(2-phenoxy-
phenyl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (36). This com-
pound was prepared using Method 10 using 2-phenoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(2-
phenoxyphenyl)-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA
1
TFA salt. LCMS: m/z (M + H)+ = 519.2; H NMR (400 MHz,
DMSO-d6): δ 9.03 (d, J = 1.3 Hz, 1H), 8.19 (d, J = 1.4 Hz, 1H), 8.07
(d, J = 8.6 Hz, 2H), 7.56−7.46 (m, 3H), 7.34 (d, J = 7.7 Hz, 1H),
7.29 (d, J = 8.4 Hz, 1H), 7.12 (t, J = 7.0 Hz, 1H), 4.63 (h, J = 6.0 Hz,
1H), 2.62 (d, J = 17.7 Hz, 1H), 2.50 (d, J = 16.1 Hz, 1H), 2.40 (d, J =
16.3 Hz, 1H), 2.15 (d, J = 17.7 Hz, 1H), 1.13 (d, J = 5.9 Hz, 3H),
1.04 (d, J = 6.0 Hz, 3H), 0.97 (s, 3H), 0.93 (s, 3H); HRMS (ESI): m/
z (M + H)+ calcd for C29H28ClN2O3S, 519.1504; found, 519.1492.
Retention time = 4.026 min.
1
salt. LCMS: m/z (M + H)+ = 553.1; H NMR (400 MHz, DMSO-
d6): δ 8.99 (s, 1H), 8.20 (s, 1H), 8.05 (d, J = 8.3 Hz, 2H), 7.60−7.48
(m, 4H), 7.34 (dt, J = 18.2, 7.6 Hz, 3H), 7.08 (dt, J = 7.6, 3.3 Hz,
2H), 6.98 (d, J = 8.0 Hz, 2H), 2.68 (d, J = 17.8 Hz, 1H), 2.53−2.35
(m, 3H), 1.01 (s, 3H), 0.89 (s, 3H); HRMS (ESI): m/z (M + H)+
calcd for C32H26ClN2O3S, 553.1347; found, 553.1347. Retention time
= 4.048 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(o-tolyl)-7,8-
dihydroquinoline-2,5(1H,6H)-dione (31). This compound was
prepared using Method 10 using o-toluidine in step 3 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(o-tolyl)-7,8-dihy-
droquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+
1-(2-(Benzyloxy)phenyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (37). This com-
pound was prepared using Method 10 using 2-(benzyloxy)aniline in
step 3 to afford 1-(2-(benzyloxy)phenyl)-3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as
1
= 475.1; H NMR (400 MHz, DMSO-d6): δ 9.07 (s, 1H), 8.21 (s,
1
a TFA salt. LCMS: m/z (M + H)+ = 567.1; H NMR (400 MHz,
1H), 8.07 (d, J = 8.2 Hz, 2H), 7.60−7.39 (m, 5H), 7.32 (d, J = 7.6
Hz, 1H), 2.56 (d, J = 17.8 Hz, 1H), 2.46 (d, J = 8.1 Hz, 2H), 2.12 (d,
J = 17.9 Hz, 1H), 2.00 (s, 3H), 0.97 (s, 3H), 0.94 (s, 3H); HRMS
(ESI): m/z (M + H)+ calcd for C27H24ClN2O2S, 475.1242; found,
475.1249. Retention time = 3.934 min.
DMSO-d6): δ 9.02 (s, 1H), 8.21 (s, 1H), 8.07 (d, J = 8.5 Hz, 2H),
7.58−7.49 (m, 3H), 7.43−7.34 (m, 2H), 7.19 (dd, J = 7.4, 3.7 Hz,
6H), 5.22−5.09 (m, 2H), 2.58 (d, J = 17.8 Hz, 1H), 2.46 (d, J = 16.1
Hz, 1H), 2.35 (d, J = 16.2 Hz, 1H), 2.17 (d, J = 17.9 Hz, 1H), 0.95 (s,
3H), 0.82 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C33H28ClN2O3S, 567.1504; found, 567.1516. Retention time = 3.99
min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-ethylphenyl)-7,7-dimeth-
yl-7,8-dihydroquinoline-2,5(1H,6H)-dione (32). This compound was
prepared using Method 10 using 2-ethylaniline in step 3 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-ethylphenyl)-7,7-dimethyl-7,8-
dihydroquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M +
1-(2-Aminophenyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (38). This com-
pound was prepared using Method 10 using benzene-1,2-diamine in
step 3 to afford 1-(2-aminophenyl)-3-(4-(4-chlorophenyl)thiazol-2-
yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA
1
H)+ = 489.2; H NMR (400 MHz, DMSO-d6): δ 9.08 (s, 1H), 8.22
(s, 1H), 8.13−8.05 (m, 2H), 7.58−7.49 (m, 4H), 7.49−7.41 (m, 1H),
7.32 (d, J = 7.7 Hz, 1H), 2.63−2.50 (m, 1H), 2.49−2.40 (m, 2H),
2.34 (dd, J = 15.1, 7.5 Hz, 1H), 2.32−2.19 (m, 1H), 2.14 (d, J = 17.9
Hz, 1H), 1.08 (t, J = 7.6 Hz, 3H), 0.98 (s, 3H), 0.94 (s, 3H); HRMS
(ESI): m/z (M + H)+ calcd for C28H26ClN2O2S, 489.1398; found,
489.1417. Retention time = 4.023 min.
1
salt. LCMS: m/z (M + H)+ = 476.1; H NMR (400 MHz, DMSO-
d6): δ 9.00 (s, 1H), 8.18 (s, 1H), 8.07 (d, J = 8.2 Hz, 2H), 7.52 (d, J =
8.2 Hz, 2H), 7.18 (t, J = 7.8 Hz, 1H), 6.96 (d, J = 7.1 Hz, 1H), 6.83
(d, J = 8.1 Hz, 1H), 6.66 (t, J = 7.5 Hz, 1H), 5.30 (s, 2H), 2.57 (d, J =
17.7 Hz, 1H), 2.47 (s, 1H), 2.35 (d, J = 16.3 Hz, 1H), 2.25 (d, J =
17.7 Hz, 1H), 0.96 (s, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C26H23ClN3O2S, 476.1194; found, 476.1207. Retention time = 3.721
min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-isopropylphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (33). This com-
pound was prepared using Method 10 using 2-isopropylaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-isopropyl-
phenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(2-
(methylamino)phenyl)-7,8-dihydroquinoline-2,5(1H,6H)-dione
(39). This compound was prepared using Method 10 using N1-
methylbenzene-1,2-diamine in step 3 to afford 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-1-(2-(methylamino)phenyl)-7,8-dihydro-
quinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ =
1
TFA salt. LCMS: m/z (M + H)+ = 503.1; H NMR (400 MHz,
DMSO-d6): δ 9.07 (s, 1H), 8.20 (s, 1H), 8.07 (d, J = 8.3 Hz, 2H),
7.64−7.49 (m, 4H), 7.46−7.37 (m, 1H), 7.28 (d, J = 7.4 Hz, 1H),
2.63 (d, J = 17.9 Hz, 1H), 2.55−2.38 (m, 3H), 2.08 (d, J = 17.9 Hz,
1H), 1.14 (d, J = 6.8 Hz, 3H), 1.06 (d, J = 6.8 Hz, 3H), 0.97 (s, 3H),
0.92 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for C29H28ClN2O2S,
503.1555; found, 503.1558. Retention time = 4.121 min.
1
490.1; H NMR (400 MHz, DMSO-d6): δ 9.01 (d, J = 1.5 Hz, 1H),
8.19 (d, J = 1.4 Hz, 1H), 8.12−8.02 (m, 2H), 7.59−7.47 (m, 2H),
4933
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Article
7.37−7.27 (m, 1H), 7.01 (dd, J = 7.7, 1.6 Hz, 1H), 6.80−6.64 (m,
2H), 5.51 (q, J = 4.7 Hz, 1H), 2.69−2.51 (m, 5H), 2.40−2.30 (m,
1H), 2.13 (d, J = 17.7 Hz, 1H), 0.94 (d, J = 7.9 Hz, 6H); HRMS
(ESI): m/z (M + H)+ calcd for C27H25ClN3O2S, 490.1351; found,
490.136. Retention time = 3.845 min.
droquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M +
Na)+ = 545.1; HRMS (ESI): m/z (M + H)+ calcd for
C27H20ClF3N2NaO3S, 567.0727; found, 567.0755. Retention time =
3.96 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(pyridin-2-yl)-
7,8-dihydroquinoline-2,5(1H,6H)-dione (46). This compound was
prepared using Method 10 using pyridin-2-amine in step 3 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(pyridin-2-yl)-7,8-di-
hydroquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M +
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-(dimethylamino)-
phenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (40).
This compound was prepared using Method 10 using N1,N1-
dimethylbenzene-1,2-diamine in step 3 to afford 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2-(dimethylamino)phenyl)-7,7-dimeth-
yl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z
1
H)+ = 462.1; H NMR (400 MHz, DMSO-d6): δ 9.07 (s, 1H), 8.72
(ddd, J = 4.9, 1.9, 0.8 Hz, 1H), 8.24 (s, 1H), 8.16 (td, J = 7.7, 1.9 Hz,
1H), 8.12−8.06 (m, 2H), 7.73−7.62 (m, 2H), 7.58−7.50 (m, 2H),
2.60 (d, J = 17.8 Hz, 1H), 2.47 (s, 2H), 2.12 (d, J = 17.8 Hz, 1H),
0.98 (s, 3H), 0.96 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C25H21ClN3O2S, 462.1038; found, 462.1057. Retention time = 3.723
min.
1
(M + H)+ = 504.2; H NMR (400 MHz, DMSO-d6): δ 9.06 (d, J =
1.4 Hz, 1H), 8.21 (d, J = 1.5 Hz, 1H), 8.13−8.02 (m, 2H), 7.57−7.42
(m, 2H), 7.24 (ddd, J = 7.7, 5.0, 1.5 Hz, 3H), 7.15 (td, J = 7.5, 1.4 Hz,
1H), 2.52 (d, J = 1.4 Hz, 7H), 2.44 (s, 1H), 2.33−2.26 (m, 2H), 0.94
(d, J = 3.8 Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C28H27ClN3O2S, 504.1507; found, 504.1516. Retention time = 4.019
min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-methoxybenzyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (47). This com-
pound was prepared using Method 10 using (2-methoxyphenyl)-
methanamine in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-
(2-methoxybenzyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-
2-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-
5,6,7,8-tetrahydro-quinolin-1(2H)-yl)benzoic Acid (41). This com-
pound was prepared using Method 10 using 2-aminobenzoic acid in
step 3 to afford 2-(3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-dimethyl-
2,5-dioxo-5,6,7,8-tetrahydroquinolin-1(2H)-yl)benzoic acid as a TFA
1
dione as a TFA salt. LCMS: m/z (M + H)+ = 505.1; H NMR (400
MHz, DMSO-d6): δ 9.03 (s, 1H), 8.20 (s, 1H), 8.07 (d, J = 8.6 Hz,
2H), 7.52 (d, J = 8.6 Hz, 2H), 7.27 (t, J = 7.9 Hz, 1H), 7.08 (d, J = 8.3
Hz, 1H), 6.83 (t, J = 7.5 Hz, 1H), 6.60 (d, J = 7.6 Hz, 1H), 5.39 (s,
2H), 3.88 (s, 3H), 2.85 (s, 2H), 2.46 (d, J = 11.6 Hz, 2H), 0.94 (s,
6H); HRMS (ESI): m/z (M + H)+ calcd for C28H26ClN2O3S,
505.1347; found, 505.1334. Retention time = 3.997 min.
1
salt. LCMS: m/z (M + H)+ = 505.1; H NMR (400 MHz, DMSO-
d6): δ 13.21 (s, 1H), 9.04 (s, 1H), 8.19 (s, 1H), 8.13 (d, J = 7.5 Hz,
1H), 8.07 (d, J = 8.6 Hz, 2H), 7.80 (s, 1H), 7.68 (t, J = 7.5 Hz, 1H),
7.52 (d, J = 8.6 Hz, 2H), 7.47 (d, J = 7.6 Hz, 1H), 2.66−2.55 (m,
1H), 2.41−2.27 (m, 2H), 2.14 (d, J = 17.7 Hz, 1H), 0.97 (s, 3H),
0.89 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for C27H22ClN2O4S,
505.0983; found, 505.1001. Retention time = 3.523 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-fluorophenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (42). This com-
pound was prepared using Method 10 using 2-fluoroaniline in step
3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-fluorophenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt.
LCMS: m/z (M + H)+ = 479.1; H NMR (400 MHz, DMSO-d6):
1
δ 9.06 (s, 1H), 8.23 (s, 1H), 8.07 (d, J = 8.4 Hz, 2H), 7.71−7.49 (m,
5H), 7.49−7.42 (m, 1H), 2.61 (d, J = 17.8 Hz, 1H), 2.48 (d, J = 2.0
Hz, 2H), 2.31 (d, J = 17.7 Hz, 1H), 0.99 (s, 3H), 0.94 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C26H21ClFN2O2S, 479.0991;
found, 479.0991. Retention time = 3.885 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(1-phenyleth-
yl)-7,8-dihydroquinoline-2,5(1H,6H)-dione (48). Step 1 1-((4,4-
Dimethyl-2,6-dioxocyclohexylidene)methyl)urea: To a solution of
triethyl orthoformate (0.89 mL, 5.35 mmol) and urea (214 mg, 3.57
mmol) in DMF (1.5 mL) was added isopropanol (10 mL). The
resulting solution was heated at 80 °C for 2 h and cooled to 0 °C. A
white precipitate formed and was removed by filtration (washed with
water and hexanes). 1-((4,4-Dimethyl-2,6-dioxocyclohexylidene)-
methyl)urea was isolated as a white solid (480 mg, 64%); LCMS:
m/z (M + H)+ = 211.1.
1-(2-Chlorophenyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (43). This com-
pound was prepared using Method 10 using 2-chloroaniline in step
3 to afford 1-(2-chlorophenyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-
7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt.
1
LCMS: m/z (M + H)+ = 495.1; H NMR (400 MHz, DMSO-d6): δ
9.07 (s, 1H), 8.23 (s, 1H), 8.07 (d, J = 8.5 Hz, 2H), 7.83−7.76 (m,
1H), 7.63 (dd, J = 3.4, 1.9 Hz, 3H), 7.53 (d, J = 8.3 Hz, 2H), 2.60 (d,
J = 17.8 Hz, 1H), 2.47 (s, 2H), 2.12 (d, J = 17.8 Hz, 1H), 0.98 (s,
3H), 0.95 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C26H21Cl2N2O2S, 495.0695; found, 495.0716. Retention time = 3.956
min.
Step 2 3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-7,8-dihy-
dro-2H-chromene-2,5(6H)-dione: A mixture of 1-((4,4-dimethyl-2,6-
dioxocyclohexylidene)methyl)urea (40 mg, 0.19 mmol), nitrile 1 (54
mg, 0.23 mmol), and a solution of benzyltrimethylammonium
hydroxide (40% in MeOH, 0.113 mL, 0.285 mmol) in DMF/
MeOH (1:1−1 mL) was heated at 140 °C for 1 h 20 min. Upon
cooling, the mixture was diluted with water, acidified at 0 °C with 1 N
HCl, stirred overnight, and filtered to afford a brown solid (3-(4-(4-
chlorophenyl)thiazol-2-yl)-7,7-dimethyl-7,8-dihydro-2H-chromene-
2,5(6H)-dione, 61 mg, 91%); LCMS: m/z (M + H)+ = 386.0.
Step 3 (48): A solution of 3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-
dimethyl-7,8-dihydro-2H-chromene-2,5(6H)-dione (34 mg, 0.088
mmol) and 1-phenylethan-1-amine (20.6 mg, 0.17 mmol) in DMF
(1.0 mL) was heated at 150 °C for 2 h. The crude mixture was diluted
with DMSO and purified by reverse-phase chromatography (Stand-
ard Acidic Gradient Method) to afford as a TFA salt, 3-(4-(4-
chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(1-phenylethyl)-7,8-dihy-
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(2-
(trifluoromethyl)phenyl)-7,8-dihydroquinoline-2,5(1H,6H)-dione
(44). This compound was prepared using Method 10 using 2-
(trifluoromethyl)aniline in step 3 to afford 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-1-(2-(trifluoromethyl)phenyl)-7,8-dihydro-
quinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ =
1
529.1; H NMR (400 MHz, DMSO-d6): δ 9.05 (d, J = 1.5 Hz, 1H),
8.23 (d, J = 1.6 Hz, 1H), 8.10−8.01 (m, 3H), 7.97 (t, J = 7.8 Hz, 1H),
7.84 (t, J = 7.8 Hz, 1H), 7.72 (d, J = 7.9 Hz, 1H), 7.57−7.48 (m, 2H),
2.70−2.55 (m, 2H), 2.42−2.27 (m, 1H), 2.10 (d, J = 17.9 Hz, 1H),
0.98 (s, 3H), 0.90 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C27H21ClF3N2O2S, 529.0959; found, 529.0976. Retention time =
3.936 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-1-(2-
(trifluoromethoxy)phenyl)-7,8-dihydroquinoline-2,5(1H,6H)-dione
(45). This compound was prepared using Method 10 using 2-
(trifluoromethoxy)aniline in step 3 to afford 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-1-(2-(trifluoromethoxy)phenyl)-7,8-dihy-
1
droquinoline-2,5(1H,6H)-dione. LCMS: m/z (M + H)+ = 489.1; H
NMR (400 MHz, DMSO-d6): δ 9.00 (s, 1H), 8.19 (s, 1H), 8.09−8.02
(m, 2H), 7.55−7.48 (m, 2H), 7.34 (t, J = 7.5 Hz, 2H), 7.30−7.19 (m,
3H), 3.06 (m, 1H), 2.69−2.51 (m, 2H), 2.13 (d, J = 17.7 Hz,
2H),1.93 (d, J = 6.9 Hz, 3H), 0.95 (s, 3, H), 0.94 (s, 3H); HRMS
4934
https://doi.org/10.1021/acs.jmedchem.1c00019
J. Med. Chem. 2021, 64, 4913−4946

Journal of Medicinal Chemistry
pubs.acs.org/jmc
Article
(ESI): m/z (M + H)+ calcd for C28H26ClN2O2S, 489.1398; found,
489.1375. Retention time = 4.042 min.
pound was prepared using Method 10 using 2,4-dimethoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,4-dimethox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
1
TFA salt. LCMS: m/z (M + H)+ = 521.13; H NMR (400 MHz,
CDCl3): δ 9.33 (s, 1H), 8.03−7.96 (m, 2H), 7.56 (s, 1H), 7.42 (dd, J
= 8.8, 2.2 Hz, 2H), 7.11 (d, J = 9.1 Hz, 1H), 6.70−6.64 (m, 2H), 3.90
(s, 3H), 3.78 (s, 3H), 2.55−2.45 (m, 3H), 2.34 (d, J = 17.9 Hz, 1H),
1.06 (d, J = 6.4 Hz, 6H). Aliphatic region complicated significantly by
amide rotamers; HRMS (ESI): m/z (M + H)+ calcd for
C28H26ClN2O4S, 521.1296; found, 521.1308. Retention time =
3.882 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-isopropyl-7,7-dimethyl-7,8-
dihydroquinoline-2,5(1H,6H)-dione (49). This compound was
prepared according to the method used to make compound 48
using isopropylamine in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-
2-yl)-1-isopropyl-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (55). This com-
pound was prepared using Method 10 using 2,6-dimethoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-dimethox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
1
dione as a TFA salt. LCMS: m/z (M + H)+ = 427.1; H NMR (400
MHz, DMSO-d6): δ 8.94 (s, 1H), 8.21 (s, 1H), 8.12−8.03 (m, 2H),
7.57−7.48 (m, 2H), 4.81 (br s, 1H), 3.08 (s, 2H), 2.45 (s, 2H), 1.60
(d, J = 6.7 Hz, 6H), 1.08 (s, 6H); HRMS (ESI): m/z (M + H)+ calcd
for C23H24ClN2O2S, 427.1242; found, 427.1242. Retention time =
3.952 min.
1
TFA salt. LCMS: m/z (M + H)+ = 521.13; H NMR (400 MHz,
DMSO-d6): δ 9.05 (s, 1H), 8.22 (s, 1H), 8.13−8.04 (m, 2H), 7.58−
7.49 (m, 3H), 6.91 (d, J = 8.6 Hz, 2H), 3.75 (s, 6H), 2.52−2.46 (m,
3H), 2.35 (d, J = 17.9 Hz, 1H), 0.96 (s, 6H); HRMS (ESI): m/z (M
+ H)+ calcd for C28H26ClN2O4S, 521.1296; found, 521.1318.
Retention time = 3.864 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-cyclohexyl-7,7-dimethyl-
7,8-dihydroquinoline-2,5(1H,6H)-dione (50). This compound was
prepared using Method 10 using cyclohexanamine in step 3 to afford
3-(4-(4-chlorophenyl)thiazol-2-yl)-1-cyclohexyl-7,7-dimethyl-7,8-di-
hydroquinoline-2,5(1H,6H)-dione as a TFA salt. LCMS: m/z (M +
3-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-
5,6,7,8-tetrahydroquinolin-1(2H)-yl)-2-methoxybenzoic Acid (56).
This compound was prepared using Method 10 using 3-amino-2-
methoxybenzoic acid in step 3 to afford 3-(3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-5,6,7,8-tetrahydroquinolin-
1(2H)-yl)-2-methoxybenzoic acid as a TFA salt. LCMS: m/z (M +
H)+ = 535.1; 1H NMR (400 MHz, DMSO-d6): δ 13.33 (s, 1H), 9.08
(s, 1H), 8.24 (s, 1H), 8.13−8.04 (m, 2H), 7.93 (dd, J = 7.8, 1.8 Hz,
1H), 7.64 (d, J = 7.4 Hz, 1H), 7.58−7.49 (m, 2H), 7.42 (t, J = 7.8 Hz,
1H), 3.62 (s, 3H), 2.57 (d, J = 17.8 Hz, 1H), 2.53 (s, 1H), 2.46−2.40
(m, 1H), 2.32 (d, J = 17.8 Hz, 1H), 0.99 (s, 3H), 0.96 (s, 3H);
HRMS (ESI): m/z (M + H)+ calcd for C28H24ClN2O5S, 535.1089;
found, 535.1078. Retention time = 3.604 min.
4-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-
5,6,7,8-tetrahydroquinolin-1(2H)-yl)-3-methoxybenzoic Acid (57).
This compound was prepared using Method 10 using 4-amino-3-
methoxybenzoic acid in step 3 to afford 4-(3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-5,6,7,8-tetrahydroquinolin-
1(2H)-yl)-3-methoxybenzoic acid as a TFA salt. LCMS: m/z (M +
H)+ = 535.1; 1H NMR (400 MHz, DMSO-d6): δ 13.37 (s, 1H), 9.06
(s, 1H), 8.23 (s, 1H), 8.12−8.05 (m, 2H), 7.75 (d, J = 7.8 Hz, 2H),
7.53 (dd, J = 8.2, 6.3 Hz, 3H), 3.84 (s, 3H), 2.62−2.50 (m, 2H),
2.49−2.40 (m, 1H), 2.22 (d, J = 17.7 Hz, 1H), 0.99 (s, 3H), 0.94 (s,
3H); HRMS (ESI): m/z (M + H)+ calcd for C28H24ClN2O5S,
535.1089; found, 535.1099. Retention time = 3.643 min.
3-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-
5,6,7,8-tetrahydroquinolin-1(2H)-yl)-4-methoxybenzoic Acid (58).
This compound was prepared using Method 10 using 3-amino-4-
methoxybenzoic acid in step 3 to afford 3-(3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-5,6,7,8-tetrahydroquinolin-
1(2H)-yl)-4-methoxybenzoic acid as a TFA salt. LCMS: m/z (M +
H)+ = 535.1; 1H NMR (400 MHz, DMSO-d6): δ 13.01 (s, 1H), 9.05
(s, 1H), 8.23 (s, 1H), 8.15 (dd, J = 8.7, 2.2 Hz, 1H), 8.12−8.05 (m,
2H), 7.94 (d, J = 2.2 Hz, 1H), 7.57−7.51 (m, 2H), 7.41 (d, J = 8.8
Hz, 1H), 3.86 (s, 3H), 2.62 (d, J = 17.9 Hz, 1H), 2.55−2.49 (m, 1H),
2.47−2.39 (m, 1H), 2.19 (d, J = 17.8 Hz, 1H), 0.99 (s, 3H), 0.94 (s,
3H); HRMS (ESI): m/z (M + H)+ calcd for C28H24ClN2O5S,
535.1089; found, 535.1112. Retention time = 3.596 min.
2-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-
5,6,7,8-tetrahydroquinolin-1(2H)-yl)-3-methoxybenzoic Acid (59).
This compound was prepared using Method 10 using 2-amino-3-
methoxybenzoic acid in step 3 to afford 2-(3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-5,6,7,8-tetrahydroquinolin-
1(2H)-yl)-3-methoxybenzoic acid as a TFA salt. LCMS: m/z (M +
H)+ = 535.1; 1H NMR (400 MHz, DMSO-d6): δ 13.19 (s, 1H), 9.05
(s, 1H), 8.21 (s, 1H), 8.12−8.04 (m, 2H), 7.76−7.65 (m, 2H), 7.61−
7.50 (m, 3H), 3.81 (s, 3H), 2.58−2.49 (m, 2H), 2.37 (d, J = 2.8 Hz,
2H), 0.97 (s, 3H), 0.94 (s, 3H); HRMS (ESI): m/z (M + H)+ calcd
1
H)+ = 467.2; H NMR (400 MHz, DMSO-d6): δ 8.93 (s, 1H), 8.19
(s, 1H), 8.05 (d, J = 8.3 Hz, 2H), 7.51 (d, J = 8.4 Hz, 2H), 4.35−4.20
(m, 1H), 2.73−2.66 (m, 3H), 2.54−2.39 (m, 2H), 1.81 (d, J = 12.8
Hz, 2H), 1.68 (t, J = 14.3 Hz, 3H), 1.43 (d, J = 13.2 Hz, 2H), 1.22 (d,
J = 9.9 Hz, 2H), 1.07 (s, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C26H28ClN2O2S, 467.1555; found, 467.1555. Retention time = 4.193
min.
Methyl 2-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-
dioxo-5,6,7,8-tetrahydro-quinolin-1(2H)-yl)thiophene-3-carboxy-
late (51). This compound was prepared using Method 10 using
methyl 2-aminothiophene-3-carboxylate in step 3 to afford methyl 2-
(3-(4-(4-chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-5,6,7,8-
tetrahydroquinolin-1(2H)-yl)thiophene-3-carboxylate as a TFA salt.
1
LCMS: m/z (M + H)+ = 525.07; H NMR (400 MHz, CDCl3): δ
9.34 (s, 1H), 8.02−7.95 (m, 2H), 7.61 (d, J = 5.7 Hz, 1H), 7.58 (s,
1H), 7.50 (t, J = 6.0 Hz, 1H), 7.45−7.39 (m, 2H), 3.71 (s, 3H),
2.61−2.45 (m, 4H), 1.08 (d, J = 9.4 Hz, 6H). Aliphatic region
complicated significantly by amide rotamers; HRMS (ESI): m/z (M +
H)+ calcd for C26H22ClN2O4S2, 525.0704; found, 525.071. Retention
time = 3.812 min.
2-(3-(4-(4-Chlorophenyl)thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-
5,6,7,8-tetrahydroquinolin-1(2H)-yl)thiophene-3-carbonitrile (52).
This compound was prepared using Method 10 using 2-amino-
thiophene-3-carbonitrile in step 3 to afford 2-(3-(4-(4-chlorophenyl)-
thiazol-2-yl)-7,7-dimethyl-2,5-dioxo-5,6,7,8-tetrahydroquinolin-
1(2H)-yl)thiophene-3-carbonitrile as a TFA salt. LCMS: m/z (M +
1
H)+ = 492.1; H NMR (400 MHz, DMSO-d6): δ 9.04 (s, 1H), 8.27
(s, 1H), 8.08 (d, J = 8.7 Hz, 2H), 8.04 (d, J = 5.7 Hz, 1H), 7.65 (d, J =
5.7 Hz, 1H), 7.53 (d, J = 8.6 Hz, 2H), 2.68 (d, J = 17.8 Hz, 2H), 2.51
(m, 2H), 1.02 (s, 3H), 1.00 (s, 3H); HRMS (ESI): m/z (M + H)+
calcd for C25H19ClN3O2S2, 492.0602; found, 492.0606. Retention
time = 3.776 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,3-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (53). This com-
pound was prepared using Method 10 using 2,3-dimethoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,3-dimethox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
1
TFA salt. LCMS: m/z (M + H)+ = 521.13; H NMR (400 MHz,
CDCl3): δ 9.36 (s, 1H), 8.00 (d, J = 7.8 Hz, 2H), 7.57 (d, J = 0.9 Hz,
1H), 7.42 (d, J = 7.7 Hz, 2H), 7.26 (s, 1H), 7.12 (d, J = 8.4 Hz, 1H),
6.81 (d, J = 7.9 Hz, 1H), 3.97 (d, J = 0.6 Hz, 3H), 3.76 (d, J = 0.9 Hz,
3H), 2.53−2.36 (m, 4H), 1.07 (t, J = 9.8 Hz, 6H). Aliphatic region
complicated significantly by amide rotamers; HRMS (ESI): m/z (M +
H)+ calcd for C28H26ClN2O4S, 521.1296; found, 521.1272. Retention
time = 3.908 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,4-dimethoxyphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (54). This com-
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1
for C28H24ClN2O5S, 535.1089; found, 535.1099. Retention time =
3.547 min.
dione as a TFA salt. LCMS: m/z (M + H)+ = 503.2; H NMR (400
MHz, DMSO-d6): δ 9.10 (s, 1H), 8.22 (s, 1H), 8.08 (d, J = 8.6 Hz,
2H), 7.53 (d, J = 8.6 Hz, 2H), 7.44 (t, J = 7.6 Hz, 1H), 7.34 (t, J = 8.0
Hz, 2H), 2.50 (d, J = 2.8 Hz, 2H), 2.32 (d, J = 14.0 Hz, 3H), 2.21−
2.10 (m, 1H), 1.96 (s, 3H), 1.16−1.01 (m, 3H), 0.95 (s, 6H); HRMS
(ESI): m/z (M + H)+ calcd for C29H28ClN2O2S, 503.1555; found,
503.1562. Retention time = 4.101 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-methoxy-6-methylphen-
yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (60). This
compound was prepared using Method 10 using 2-methoxy-6-
methylaniline in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-
1-(2,3-dimethoxyphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5-
1
(1H,6H)-dione as a TFA salt. LCMS: m/z (M + H)+ = 505.1; H
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (66). This com-
pound was prepared using Method 10 using 2-(4-(4-chlorophenyl)-
thiazol-2-yl)acetonitrile in step 2 and 2,6-diethylaniline in step 3 to
afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-7,7-
dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a TFA salt.
NMR (400 MHz, DMSO-d6): δ 9.08 (s, 1H), 8.23 (s, 1H), 8.13−8.02
(m, 2H), 7.58−7.42 (m, 3H), 7.16−7.03 (m, 2H), 3.74 (s, 3H),
2.48−2.37 (m, 2H), 2.269 (m, 2H), 1.99 (s, 3H), 0.96 (s, 3H), 0.95
(s, 3H); HRMS (ESI): m/z (M + H)+ calcd for C28H26ClN2O3S,
505.1347; found, 505.135. Retention time = 3.963 min.
LCMS: m/z (M + H)+ = 517.2; H NMR (400 MHz, DMSO-d6):
1
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-methoxypyridin-3-yl)-
7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (61). This
compound was prepared using Method 10 using 2-methoxypyridin-
3-amine in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-
methoxypyridin-3-yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-
dione as a TFA salt. LCMS: m/z (M + H)+ = 492.11; 1H NMR (400
MHz, CD3OD): δ 9.04 (s, 1H), 8.39−8.38 (m, 1H), 8.22 (s, 1H),
8.07 (d, J = 8.4 Hz, 2H), 7.91−7.89 (m, 1H), 7.52 (d, J = 8.4 Hz,
2H), 7.27 (d, J = 8.4 Hz, 1H), 3.86 (s, 3H), 3.66−3.53 (m, 1H),
3.47−3.32 (m, 1H), 2.57 (d, J = 20 Hz, 1H), 2.23 (d, J = 20 Hz, 1H),
1.19−0.94 (m, 6H). Aliphatic region complicated significantly by
amide rotamers; HRMS (ESI): m/z (M + H)+ calcd for
C26H23ClN3O3S, 492.1143; found, 492.116. Retention time = 3.836
min.
δ 9.11 (s, 1H), 8.23 (s, 1H), 8.13−8.05 (m, 2H), 7.59−7.47 (m, 3H),
7.38 (d, J = 7.7 Hz, 2H), 2.51 (s, 2H), 2.40−2.26 (m, 4H), 2.16 (dq, J
= 15.0, 7.5 Hz, 2H), 1.07 (t, J = 7.5 Hz, 6H), 0.95 (s, 6H); HRMS
(ESI): m/z (M + H)+ calcd for C30H30ClN2O2S, 517.1711; found,
517.1699. Retention time = 4.187 min.
Method 11: Methyl 5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-
diethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxylate
(67). Step 1: In a vial, methyl 3-oxobutanoate (0.385 mL, 3.57 mmol)
and DMF−DMA (0.474 mL, 3.57 mmol) were mixed and heated well
at 100 °C for 15 min. The reaction mixture became red oil.
Step 2: To the mixture were added i-PrOH (40 mL), 2-(4-(4-
chlorophenyl)thiazol-2-yl)acetonitrile N1/IVa (837 mg, 3.57 mmol),
and potassium tert-butoxide (400 mg, 3.57 mmol). The reaction
mixture was allowed to stir at rt for 2 h at which point the solvent was
removed.
Step 3: To the resulting residue were added acetic acid (30 mL)
and 2,6-dimethylaniline (646 μL, 3.9 mmol). The reaction mixture
was stirred for 15 min and the mixture was diluted with water and
extracted (EtOAc × 2). The organic layers were combined (not dried
with magnesium sulfate) and concentrated.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(4-methoxypyridin-3-yl)-
7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (62). This
compound was prepared using Method 10 using 4-methoxypyridin-
3-amine in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(4-
methoxypyridin-3-yl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-
dione as a TFA salt. LCMS: m/z (M + H)+ = 492.11; 1H NMR (400
MHz, CD3OD): δ 9.01 (s, 1H), 8.21−8.19 (m, 2H), 8.08−8.06 (m,
2H), 7.88−7.86 (m, 1H), 7.52 (d, J = 8.4 Hz, 2H), 6.48 (d, J = 8.4
Hz, 1H), 3.76 (s, 3H), 3.68−3.64 (m, 1H), 2.77−2.73 (m, 2H),
2.41−2.41 (m, 1H), 1.20−0.96 (m, 6H). Aliphatic region complicated
significantly by amide rotamers; HRMS (ESI): m/z (M + H)+ calcd
for C26H23ClN3O3S, 492.1143; found, 492.1148. Retention time =
3.133 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,5-diethoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (63). This com-
pound was prepared using Method 10 using 2,5-diethoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,5-diethox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
Step 4: The residue was taken up in DMF (40 mL) and heated at
125 °C for 1.5 h. The reaction mixture was diluted with water and
EtOAc and extracted (2×); the organic layers were combined, dried
with Na2SO4, and concentrated. The crude mixture was diluted with
DMSO and purified by reverse-phase chromatography (Standard
Acidic Gradient Method) to afford as a TFA salt, methyl 5-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-6-oxo-1,6-
dihydropyridine-3-carboxylate (1.05 g, 60%); LCMS: m/z (M + H)+
1
TFA salt. LCMS: m/z (M + H)+ = 549.16; H NMR (400 MHz,
CDCl3): δ 9.34 (s, 1H), 8.03−7.97 (m, 2H), 7.57 (s, 1H), 7.42 (d, J =
8.5 Hz, 2H), 7.04 (d, J = 1.6 Hz, 2H), 6.78−6.75 (m, 1H), 4.10−3.95
(m, 4H), 2.50 (d, J = 18.4 Hz, 3H), 2.36 (d, J = 18.0 Hz, 1H), 1.42 (t,
J = 7.0 Hz, 3H), 1.19 (t, J = 7.0 Hz, 3H), 1.07 (t, J = 7.3 Hz, 6H).
Aliphatic region complicated significantly by amide rotamers; HRMS
(ESI): m/z (M + H)+ calcd for C30H30ClN2O4S, 549.1603; found,
549.1609. Retention time = 4.023 min.
1
= 493.1; H NMR (400 MHz, DMSO-d6): δ 9.14 (s, 1H), 8.22 (s,
1H), 8.12−8.03 (m, 2H), 7.59−7.44 (m, 3H), 7.36 (d, J = 7.7 Hz,
2H), 3.89 (s, 3H), 3.31 (s, 7H), 2.61−2.50 (m, 1H), 2.47−2.34 (m,
3H), 2.33−2.07 (m, 8H), 1.05 (t, J = 7.5 Hz, 6H), 1.00 (t, J = 7.6 Hz,
0H), 0.82 (s, 1H); HRMS (ESI): m/z (M + H)+ calcd for
C27H26ClN2O3S, 493.1347; found, 493.1338. Retention time = 4.247
min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-meth-
yl-6-oxo-1,6-dihydropyridine-3-carboxylic Acid (68). To a solution
of methyl 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-
methyl-6-oxo-1,6-dihydropyridine-3-carboxylate (1.0 g, 2.03 mmol,
compound 67) in THF (10 mL) and MeOH (10 mL) was added
lithium hydroxide (0.168 g, 14.22 mmol) and the mixture became
yellow. The mixture was stirred for 1 h at 70 °C, concentrated with a
stream of air, and diluted with DCM. The pH of the aqueous layer
was adjusted to pH 7 using 1 N HCl, the mixture was extracted with 2
× 25 mL DCM, and the organic layers were dried with Na2SO4 and
concentrated. The crude mixture was diluted with DMSO and
purified by reverse-phase chromatography (Standard Acidic Gra-
dient Method) to afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethoxyphenyl)-7,7-di-
methyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (64). This com-
pound was prepared using Method 10 using 2,6-diethoxyaniline in
step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethox-
yphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione as a
1
TFA salt. LCMS: m/z (M + H)+ = 549.16; H NMR (400 MHz,
CDCl3): δ 9.34 (s, 1H), 8.03−7.97 (m, 2H), 7.56 (s, 1H), 7.45−7.34
(m, 3H), 6.70 (dd, J = 8.5, 3.8 Hz, 2H), 4.06 (hd, J = 9.8, 7.2 Hz,
4H), 2.49 (s, 2H), 2.40 (s, 2H), 1.22 (t, J = 7.0 Hz, 6H), 1.07 (d, J =
11.2 Hz, 6H). Aliphatic region complicated significantly by amide
rotamers; HRMS (ESI): m/z (M + H)+ calcd for C30H30ClN2O4S,
549.161; found, 549.1609. Retention time = 4.023 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-ethyl-6-methylphenyl)-
7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-dione (65). This
compound was prepared using Method 10 using 2-ethyl-6-methylani-
line in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2-ethyl-
6-methylphenyl)-7,7-dimethyl-7,8-dihydroquinoline-2,5(1H,6H)-
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diethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid;
1.20 (d, J = 6.6 Hz, 6H), 1.08 (t, J = 7.5 Hz, 6H); HRMS (ESI): m/z
(M + H)+ calcd for C29H31ClN3O2S, 520.182; found, 520.1817.
Retention time = 3.916 min.
1
LCMS: m/z (M + H)+ = 478.7; H NMR (400 MHz, DMSO-d6): δ
13.33 (s, 1H), 9.17 (s, 1H), 8.19 (s, 1H), 8.11−8.02 (m, 2H), 7.57−
7.42 (m, 3H), 7.35 (d, J = 7.7 Hz, 2H), 2.34−2.19 (m, 5H), 2.14 (dq,
J = 15.1, 7.5 Hz, 2H), 1.04 (t, J = 7.6 Hz, 6H); HRMS (ESI): m/z (M
+ H)+ calcd for C26H24ClN2O3S, 479.1191; found, 479.1186.
Retention time = 3.835 min.
N-(tert-Butyl)-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide (73).
This compound was prepared using Method 12 using 2-
methylpropan-2-amine to afford N-(tert-butyl)-5-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-6-oxo-1,6-
Ethyl 5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-
oxo-2-phenyl-1,6-dihydro-pyridine-3-carboxylate (69). This com-
pound was prepared using Method 11 using ethyl 3-oxo-3-
phenylpropanoate in step 1 to afford ethyl 5-(4-(4-chlorophenyl)-
thiazol-2-yl)-1-(2,6-diethylphenyl)-6-oxo-2-phenyl-1,6-dihydropyri-
1
dihydropyridine-3-carboxamide. LCMS: m/z (M + H)+ = 534.1; H
NMR (400 MHz, DMSO-d6): δ 8.68 (s, 1H), 8.49 (d, J = 7.5 Hz,
1H), 8.20 (s, 1H), 8.10 (d, J = 8.5 Hz, 2H), 7.54 (d, J = 8.5 Hz, 2H),
7.48 (dd, J = 8.2, 7.1 Hz, 1H), 7.37 (s, 1H), 7.35 (s, 1H), 4.06 (dq, J
= 13.4, 6.7 Hz, 1H), 2.32 (dq, J = 15.2, 7.6 Hz, 2H), 2.18 (dq, J =
15.1, 7.5 Hz, 2H), 2.00 (s, 3H), 1.20 (d, J = 6.6 Hz, 6H), 1.08 (t, J =
7.5 Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for C30H33ClN3O2S,
534.1977; found, 534.1983. Retention time = 4.032 min.
1
dine-3-carboxylate. LCMS: m/z (M + H)+ = 569.2; H NMR (400
MHz, DMSO-d6): δ 9.16 (s, 1H), 8.28 (s, 1H), 8.15−8.02 (m, 2H),
7.62−7.46 (m, 2H), 7.26−7.01 (m, 8H), 3.91 (q, J = 7.1 Hz, 2H),
2.60−2.48 (m, 1H), 2.47−2.15 (m, 6H), 1.04 (t, J = 7.5 Hz, 6H),
0.78 (t, J = 7.1 Hz, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C33H30ClN2O3S, 569.166; found, 569.1643. Retention time = 4.366
min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-N-iso-
butyl-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide (74).
This compound was prepared using Method 12 using 2-
methylpropan-1-amine to afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-
1-(2,6-diethylphenyl)-N-isobutyl-2-methyl-6-oxo-1,6-dihydropyri-
1
dine-3-carboxamide. LCMS: m/z (M + H)+ = 534.2; H NMR (400
MHz, DMSO-d6): δ 8.70 (s, 1H), 8.61 (t, J = 5.8 Hz, 1H), 8.18 (d, J =
0.6 Hz, 1H), 8.07 (d, J = 8.5 Hz, 2H), 7.52 (d, J = 8.5 Hz, 2H), 7.46
(dd, J = 8.2, 7.1 Hz, 1H), 7.35 (s, 1H), 7.33 (s, 1H), 3.08 (dd, J = 6.8,
5.8 Hz, 2H), 2.29 (dq, J = 15.2, 7.6 Hz, 2H), 2.15 (dq, J = 15.1, 7.5
Hz, 2H), 2.00 (s, 3H), 1.83 (dt, J = 13.4, 6.7 Hz, 1H), 1.08 (t, J = 7.5
Hz, 6H), 0.91 (d, J = 6.6 Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd
for C30H33ClN3O2S, 534.1977; found, 534.1974. Retention time =
4.012 min.
Method 12: 5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-N,2-dimethyl-6-oxo-1,6-dihydropyridine-3-carboxamide
(70). To a solution of 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-
diethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid,
compound 68 (250 mg, 0.522 mmol), in DMF (volume: 5 mL) were
added 2-(3H-[1,2,3]triazolo[4,5-b]pyridin-3-yl)-1,1,3,3-tetramethyli-
souronium hexafluorophosphate(V) (397 mg, 1.044 mmol), N-
ethyl-N-isopropylpropan-2-amine (365 μL, 2.088 mmol), and
methanamine (1044 μL, 2.088 mmol). The mixture became yellow
and the reaction mixture was stirred for 6 h at 60 °C, diluted with
water, extracted with 3 × 10 mL DCM, and washed with brine. The
organic layer was dried and concentrated. The crude mixture was
diluted with DMSO and purified by reverse-phase chromatography
(Standard Acidic Gradient Method) to afford 5-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-N,2-dimethyl-6-oxo-
1,6-dihydropyridine-3-carboxamide; LCMS: m/z (M + H)+ = 492.1;
1H NMR (400 MHz, DMSO-d6): δ 8.73 (s, 1H), 8.54 (d, J = 4.7 Hz,
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-N-(2-hy-
droxyethyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide
(75). This compound was prepared using Method 12 using 2-
aminoethan-1-ol to afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-
diethylphenyl)-N-(2-hydroxyethyl)-2-methyl-6-oxo-1,6-dihydropyri-
1
dine-3-carboxamide. LCMS: m/z (M + H)+ = 522.1; H NMR (400
MHz, DMSO-d6): δ 8.71 (s, 1H), 8.61 (t, J = 5.6 Hz, 1H), 8.18 (d, J =
0.6 Hz, 1H), 8.15−8.00 (m, 2H), 7.56−7.49 (m, 2H), 7.46 (dd, J =
8.2, 7.1 Hz, 1H), 7.35 (s, 1H), 7.33 (s, 1H), 3.53 (t, J = 6.1 Hz, 2H),
3.35−3.30 (m, 2H), 3.14 (s, 1H), 2.29 (dd, J = 15.1, 7.6 Hz, 2H),
2.15 (dq, J = 15.1, 7.5 Hz, 2H), 2.00 (s, 3H), 1.08−1.02 (m, 6H);
HRMS (ESI): m/z (M + H)+ calcd for C28H29ClN3O3S, 522.1613;
found, 522.1627. Retention time = 3.505 min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-N-(2-
methoxyethyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxa-
mide (76). This compound was prepared using Method 12 using 2-
methoxyethan-1-amine to afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-
1-(2,6-diethylphenyl)-N-(2-methoxyethyl)-2-methyl-6-oxo-1,6-dihy-
dropyridine-3-carboxamide. LCMS: m/z (M + H)+ = 536.1; 1H NMR
(400 MHz, DMSO-d6): δ 8.71 (d, J = 4.7 Hz, 2H), 8.21 (s, 1H), 8.11
(d, J = 8.6 Hz, 2H), 7.54 (d, J = 8.6 Hz, 2H), 7.48 (dd, J = 8.2, 7.1 Hz,
1H), 7.37 (s, 1H), 7.35 (s, 1H), 3.50 (td, J = 5.4, 1.3 Hz, 2H), 3.47−
3.39 (m, 2H), 3.31 (s, 3H), 2.39−2.26 (m, 2H), 2.18 (dq, J = 15.1,
7.5 Hz, 2H), 2.02 (s, 3H), 1.08 (t, J = 7.5 Hz, 6H); HRMS (ESI): m/
z (M + H)+ calcd for C29H31ClN3O3S, 536.1769; found, 536.1774.
Retention time = 3.789 min.
1H), 8.18 (s, 1H), 8.13−8.05 (m, 2H), 7.56−7.48 (m, 2H), 7.46 (dd,
J = 8.3, 7.1 Hz, 1H), 7.34 (d, J = 7.7 Hz, 2H), 2.96 (s, 1H), 2.78 (d, J
= 4.5 Hz, 3H), 2.27 (dt, J = 15.2, 7.6 Hz, 2H), 2.14 (dq, J = 15.1, 7.5
Hz, 2H), 2.01 (s, 3H), 1.05 (t, J = 7.6 Hz, 6H); HRMS (ESI): m/z
(M + H)+ calcd for C27H27ClN3O2S, 492.1507; found, 492.1506.
Retention time = 3.75 min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-N,N,2-
trimethyl-6-oxo-1,6-dihydropyridine-3-carboxamide (71). This
compound was prepared using Method 12 using dimethylamine to
afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-
N,N,2-trimethyl-6-oxo-1,6-dihydropyridine-3-carboxamide. LCMS:
1
m/z (M + H)+ = 506.1; H NMR (400 MHz, DMSO-d6): δ 8.58
(s, 1H), 8.19 (s, 1H), 8.10 (d, J = 8.6 Hz, 2H), 7.56−7.47 (m, 2H),
7.49−7.41 (m, 1H), 7.35 (s, 1H), 7.33 (s, 1H), 3.01 (s, 3H), 2.96 (s,
3H), 2.29 (dq, J = 15.2, 7.6 Hz, 2H), 2.16 (dq, J = 15.0, 7.5 Hz, 2H),
1.84 (s, 3H), 1.06 (t, J = 7.6 Hz, 6H); HRMS (ESI): m/z (M + H)+
calcd for C28H29ClN3O2S, 506.1664; found, 506.1659. Retention time
= 3.819 min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-N-iso-
propyl-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide (72).
This compound was prepared using Method 12 using propan-2-
amine to afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-N-isopropyl-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxa-
mide. LCMS: m/z (M + H)+ = 520.1; 1H NMR (400 MHz, DMSO-
d6): δ 8.68 (s, 1H), 8.49 (d, J = 7.5 Hz, 1H), 8.20 (s, 1H), 8.10 (d, J =
8.5 Hz, 2H), 7.54 (d, J = 8.5 Hz, 2H), 7.48 (dd, J = 8.2, 7.1 Hz, 1H),
7.37 (s, 1H), 7.35 (s, 1H), 4.06 (dq, J = 13.4, 6.7 Hz, 1H), 2.32 (dq, J
= 15.2, 7.6 Hz, 2H), 2.18 (dq, J = 15.1, 7.5 Hz, 2H), 2.00 (s, 3H),
(5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-
methyl-6-oxo-1,6-dihydro-pyridine-3-carbonyl)glycine (77). Step 1:
Followed Method 12 using methyl glycinate.
Step 2: To a solution of the crude acid from step 1 in 1:1 THF/
MeOH (∼0.3 mM) was added lithium hydroxide (∼10 equiv) and
stirred for 1 h at 70 °C. The mixture was concentrated with a stream
of air and diluted with DCM. The pH of the aqueous layer was
adjusted to pH 7 using 1 N HCl and extracted with 2× DCM; the
organic layers were dried with Na2SO4 and concentrated. The crude
mixture was diluted with DMSO and purified by reverse-phase
chromatography (Standard Acidic Gradient Method) to afford
compound 77. LCMS: m/z (M + H)+ = 536.1; 1H NMR (400 MHz,
DMSO-d6): δ 12.69 (s, 1H), 9.00 (t, J = 5.9 Hz, 1H), 8.77 (s, 1H),
8.21 (d, J = 0.6 Hz, 1H), 8.14−8.07 (m, 2H), 7.57−7.52 (m, 2H),
4937
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Article
7.49 (dd, J = 8.2, 7.2 Hz, 1H), 7.37 (d, J = 7.7 Hz, 2H), 3.96 (d, J =
5.9 Hz, 2H), 2.32 (dq, J = 15.2, 7.6 Hz, 2H), 2.18 (dq, J = 15.1, 7.5
Hz, 2H), 2.08 (s, 3H), 1.08 (td, J = 7.6, 0.6 Hz, 6H); HRMS (ESI):
m/z (M + H)+ calcd for C28H27ClN3O4S, 536.1405; found, 536.1417.
Retention time = 3.491 min.
2H), 7.57−7.45 (m, 3H), 7.43−7.32 (m, 4H), 7.18−7.09 (m, 1H),
2.42−2.28 (m, 2H), 2.21 (dq, J = 15.1, 7.5 Hz, 2H), 2.09 (s, 3H),
1.10 (t, J = 7.5 Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C32H29ClN3O2S, 554.1664; found, 554.1682. Retention time = 4.043
min.
N-(2-Aminoethyl)-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-di-
ethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide
(78). This compound was prepared using Method 12 using ethane-
1,2-diamine to afford N-(2-aminoethyl)-5-(4-(4-chlorophenyl)thiazol-
2-yl)-1-(2,6-diethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-
carboxamide as a TFA salt. LCMS: m/z (M + H)+ = 521.1; 1H NMR
(400 MHz, DMSO-d6): δ 8.86 (s, 1H), 8.77 (t, J = 5.6 Hz, 1H), 8.23
(d, J = 0.6 Hz, 1H), 8.12 (d, J = 8.4 Hz, 2H), 7.81 (s, 2H), 7.55 (d, J =
8.4 Hz, 2H), 7.53−7.45 (m, 1H), 7.38 (s, 1H), 7.36 (s, 1H), 3.51 (q, J
= 6.1 Hz, 2H), 3.04 (q, J = 5.9 Hz, 2H), 2.31 (dd, J = 15.2, 7.5 Hz,
2H), 2.17 (dq, J = 15.1, 7.5 Hz, 2H), 2.08 (s, 3H), 1.13−1.04 (m,
6H); HRMS (ESI): m/z (M + H)+ calcd for C28H30ClN4O2S,
517.1711; found, 521.1773. Retention time = 2.669 min.
N-Benzyl-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphen-
yl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide (83). This
compound was prepared using Method 12 using phenylmethanamine
to afford N-benzyl-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide. LCMS:
1
m/z (M + H)+ = 567.7; H NMR (400 MHz, DMSO-d6): δ 9.13
(t, J = 5.9 Hz, 1H), 8.77 (s, 1H), 8.18 (s, 1H), 8.12−8.04 (m, 2H),
7.57−7.41 (m, 3H), 7.41−7.21 (m, 7H), 4.48 (d, J = 5.9 Hz, 2H),
2.22 (ddq, J = 56.8, 15.1, 7.5 Hz, 4H), 2.02 (s, 3H), 1.05 (t, J = 7.5
Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for C33H31ClN3O2S,
568.182; found, 568.1842. Retention time = 3.966 min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-N-cyclohexyl-1-(2,6-diethyl-
phenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide (84).
This compound was prepared using Method 12 using cyclohexan-
amine to afford 5-(4-(4-chlorophenyl)thiazol-2-yl)-N-cyclohexyl-1-
(2,6-diethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxa-
mide. LCMS: m/z (M + H)+ = 567.7; 1H NMR (400 MHz, DMSO-
d6): δ 8.64 (s, 1H), 8.46 (d, J = 7.7 Hz, 1H), 8.17 (s, 1H), 8.11−8.04
(m, 2H), 7.56−7.41 (m, 3H), 7.33 (d, J = 7.7 Hz, 2H), 3.72 (dd, J =
7.4, 3.6 Hz, 0H), 2.30 (dq, J = 15.2, 7.6 Hz, 2H), 2.15 (dq, J = 15.1,
7.5 Hz, 2H), 1.97 (s, 3H), 1.88 (d, J = 9.6 Hz, 2H), 1.71 (s, 2H), 1.58
(d, J = 13.0 Hz, 1H), 1.35−1.22 (m, 4H), 1.05 (t, J = 7.5 Hz, 6H);
HRMS (ESI): m/z (M + H)+ calcd for C32H35ClN3O2S, 560.2133;
found, 560.2134. Retention time = 4.151 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-meth-
yl-5-(piperidine-1-carbonyl)pyridin-2(1H)-one (85). This compound
was prepared using Method 12 using piperidine to afford 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-methyl-5-(piperi-
dine-1-carbonyl)pyridin-2(1H)-one. LCMS: m/z (M + H)+ = 546.1;
1H NMR (400 MHz, DMSO-d6): δ 8.58 (d, J = 0.8 Hz, 1H), 8.22 (d,
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-meth-
yl-N-(2-(methylamino)-ethyl)-6-oxo-1,6-dihydropyridine-3-carbox-
amide (79). This compound was prepared using Method 12 using
tert-butyl(2-aminoethyl) (methyl)carbamate to afford tert-butyl(2-(5-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-6-
oxo-1,6-dihydro-pyridine-3-carboxamido)ethyl)(methyl)carbamate
followed by Boc deprotection using TFA in DCM to afford 5-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-N-(2-
(methylamino)ethyl)-6-oxo-1,6-dihydropyridine-3-carboxamide as a
1
TFA salt. LCMS: m/z (M + H)+ = 535.1; H NMR (400 MHz,
DMSO-d6): δ 8.86 (s, 1H), 8.83 (t, J = 5.7 Hz, 1H), 8.44 (s, 1H),
8.23 (s, 1H), 8.12 (d, J = 8.5 Hz, 2H), 7.56 (d, J = 8.5 Hz, 2H), 7.54−
7.45 (m, 1H), 7.39 (s, 1H), 7.37 (s, 1H), 3.55 (q, J = 6.0 Hz, 2H),
3.14 (s, 2H), 2.70−2.63 (m, 3H), 2.31 (dq, J = 15.2, 7.6 Hz, 2H),
2.17 (dq, J = 15.1, 7.5 Hz, 2H), 2.09 (s, 3H), 1.08 (t, J = 7.5 Hz, 6H);
HRMS (ESI): m/z (M + H)+ calcd for C29H32ClN4O2S, 535.1929;
found, 535.1938. Retention time = 2.712 min.
N-(2-Amino-2-oxoethyl)-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-
(2,6-diethylphenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carbox-
amide (80). This compound was prepared using Method 12 using 2-
aminoacetamide to afford N-(2-amino-2-oxoethyl)-5-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-6-oxo-1,6-
J = 0.9 Hz, 1H), 8.17−8.06 (m, 2H), 7.53 (d, J = 8.5 Hz, 2H), 7.51−
7.46 (m, 1H), 7.38 (s, 1H), 7.36 (s, 1H), 3.65 (s, 2H), 3.45 (s, 4H),
2.39−2.15 (m, 4H), 1.88 (d, J = 0.8 Hz, 3H), 1.63 (s, 4H), 1.12−1.05
(m, 6H); HRMS (ESI): m/z (M + H)+ calcd for C31H33ClN3O2S,
546.1977; found, 546.1998. Retention time = 4.064 min.
1
dihydropyridine-3-carboxamide. LCMS: m/z (M + H)+ = 535.1; H
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-meth-
yl-5-(morpholine-4-carbonyl)pyridin-2(1H)-one (86). This com-
pound was prepared using Method 12 using morpholine to afford
3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-methyl-5-
(morpholine-4-carbonyl)pyridin-2(1H)-one. LCMS: m/z (M + H)+ =
548.1; 1H NMR (400 MHz, DMSO-d6): δ 8.60 (s, 1H), 8.19 (s, 1H),
8.10 (d, J = 8.6 Hz, 2H), 7.51 (d, J = 8.5 Hz, 2H), 7.48−7.43 (m,
1H), 7.35 (s, 1H), 7.33 (s, 1H), 3.62 (m, 8H), 2.36−2.12 (m, 4H),
1.86 (d, J = 1.6 Hz, 3H), 1.11−1.01 (m, 6H); HRMS (ESI): m/z (M
+ Na)+ calcd for C30H30ClN3NaO3S, 570.1589; found, 570.1605.
Retention time = 3.787 min.
NMR (400 MHz, DMSO-d6): δ 8.80 (d, J = 7.6 Hz, 2H), 8.21 (s,
1H), 8.11 (d, J = 8.5 Hz, 2H), 7.54 (d, J = 8.6 Hz, 1H), 7.51−7.43
(m, 2H), 7.36 (d, J = 7.7 Hz, 2H), 7.06 (s, 2H), 3.84 (d, J = 5.8 Hz,
2H), 2.32 (dq, J = 15.2, 7.6 Hz, 2H), 2.18 (dq, J = 15.2, 7.5 Hz, 2H),
2.08 (s, 3H), 1.08 (t, J = 7.5 Hz, 6H); HRMS (ESI): m/z (M + H)+
calcd for C28H28ClN4O3S, 535.1565; found, 535.155. Retention time
= 3.378 min.
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-meth-
yl-N-(3-(methylamino)propyl)-6-oxo-1,6-dihydropyridine-3-car-
boxamide (81). This compound was prepared using Method 12 using
tert-butyl (3-aminopropyl)(methyl)carbamate followed by boc
deprotection using TFA in DCM to afford 5-(4-(4-chlorophenyl)-
thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-N-(3-(methylamino)-
propyl)-6-oxo-1,6-dihydropyridine-3-carboxamide as a TFA salt.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-meth-
yl-5-(piperazine-1-carbonyl)pyridin-2(1H)-one (87). This compound
was prepared using Method 12 using piperazine to afford 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-methyl-5-(pipera-
zine-1-carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z (M +
1
LCMS: m/z (M + H)+ = 549.1; H NMR (400 MHz, DMSO-d6):
δ 8.76 (d, J = 2.8 Hz, 2H), 8.34 (s, 1H), 8.23 (s, 1H), 8.11 (d, J = 8.5
Hz, 2H), 7.55 (d, J = 8.5 Hz, 2H), 7.52−7.46 (m, 1H), 7.38 (s, 1H),
7.36 (s, 1H), 3.34 (q, J = 6.5, 6.1 Hz, 2H), 2.99 (p, J = 6.6 Hz, 2H),
2.60 (t, J = 5.4 Hz, 3H), 2.31 (dq, J = 15.2, 7.6 Hz, 2H), 2.17 (dq, J =
15.1, 7.5 Hz, 2H), 2.05 (s, 3H), 1.86 (p, J = 7.0 Hz, 2H), 1.08 (t, J =
7.5 Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C30H33ClN4NaO2S, 571.1905; found, 571.1919. Retention time =
2.708 min.
1
H)+ = 547.1; H NMR (400 MHz, DMSO-d6): δ 8.56 (s, 1H), 8.19
(s, 1H), 8.16−8.03 (m, 2H), 7.57−7.36 (m, 3H), 7.34 (d, J = 7.7 Hz,
2H), 3.57 (s, 2H), 3.28 (s, 4H), 2.70 (d, J = 14.8 Hz, 1H), 2.52 (p, J =
1.9 Hz, 0H), 2.26 (dt, J = 15.2, 7.4 Hz, 2H), 2.17 (s, 3H), 1.85 (s,
3H), 1.06 (t, J = 7.5 Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C30H32ClN4O2S, 547.1929; found, 547.1942. Retention time = 2.691
min.
N-Benzyl-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphen-
yl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide (88). This
compound was prepared using Method 12 using 1-methylpiperazine
to afford N-benzyl-5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-2-methyl-6-oxo-1,6-dihydropyridine-3-carboxamide as a TFA
5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-meth-
yl-6-oxo-N-phenyl-1,6-dihydropyridine-3-carboxamide (82). This
compound was prepared using Method 12 using aniline to afford 5-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-methyl-6-
oxo-N-phenyl-1,6-dihydropyridine-3-carboxamide. LCMS: m/z (M +
H)+ = 554.1; 1H NMR (400 MHz, DMSO-d6): δ 10.63 (s, 1H), 8.88
(s, 1H), 8.23 (s, 1H), 8.12 (d, J = 8.6 Hz, 2H), 7.74 (d, J = 7.9 Hz,
1
salt. LCMS: m/z (M + H)+ = 561.2; H NMR (400 MHz, DMSO-
d6): δ 8.70 (s, 1H), 8.23 (s, 1H), 8.12 (d, J = 8.6 Hz, 2H), 7.54 (d, J =
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8.6 Hz, 2H), 7.52−7.47 (m, 1H), 7.38 (s, 1H), 7.37 (s, 1H), 3.42 (m,
8H), 2.84 (s, 3H), 2.39−3.15 (m, 4H), 1.90 (s, 3H), 1.09 (t, J = 7.5
Hz, 6H); HRMS (ESI): m/z (M + H)+ calcd for C31H34ClN4O2S,
561.2086; found, 561.2076. Retention time = 2.74 min.
Hz, 1H), 8.19−8.10 (m, 2H), 7.59−7.51 (m, 2H), 7.49 (t, J = 7.7 Hz,
1H), 7.37 (dd, J = 7.6, 4.5 Hz, 2H), 4.08 (d, J = 14.1 Hz, 1H), 3.78
(d, J = 14.7 Hz, 1H), 3.73−3.61 (m, 1H), 3.60−3.48 (m, 1H), 3.49−
3.38 (m, 1H), 3.26−3.13 (m, 1H), 3.10 (d, J = 6.0 Hz, 1H), 2.43−
2.29 (m, 2H), 2.25 (td, J = 15.0, 7.5 Hz, 1H), 2.11 (dd, J = 14.9, 7.4
Hz, 1H), 1.10 (q, J = 7.1 Hz, 14H); HRMS (ESI): m/z (M + H)+
calcd for C32H36ClN4O2S, 575.2242; found, 575.2225. Retention time
= 2.79 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-isobu-
tyl-5-(piperazine-1-carbonyl)pyridin-2(1H)-one (91). This com-
pound was prepared via Method 13 using methyl 5-methyl-3-
oxohexanoate in step 1 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-
1-(2,6-diethylphenyl)-6-isobutyl-5-(piperazine-1-carbonyl)pyridin-
1
2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ = 589.2; H NMR
(400 MHz, DMSO-d6): δ 8.93 (s, 1H), 8.73 (d, J = 0.7 Hz, 1H), 8.24
(d, J = 0.7 Hz, 1H), 8.18−8.10 (m, 2H), 7.59−7.52 (m, 2H), 7.49 (d,
J = 7.6 Hz, 1H), 7.37 (d, J = 7.7 Hz, 1H), 4.06 (s, 1H), 3.81 (s, 1H),
3.64 (m, 2H), 3.16 (m, 5H), 2.45−1.91 (m, 3H), 1.34 (dq, J = 13.5,
6.7 Hz, 1H), 1.10 (d, J = 7.9 Hz, 8H), 0.63 (d, J = 6.5 Hz, 6H);
HRMS (ESI): m/z (M + H)+ calcd for C33H38ClN4O2S, 589.2399;
found, 589.2381. Retention time = 1.982 min.
Method 13: 3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-5-(piperazine-1-carbonyl)-6-propylpyridin-2(1H)-one (89).
Steps 1−3: A mixture of ethyl 3-oxohexanoate (0.674 g, 4.26 mmol)
and 1,1-dimethoxy-N,N-dimethylmethanamine (0.566 mL, 4.26
mmol) was stirred for 1 h at 100 °C. The mixture was diluted with
IPA (10 mL). 2-(4-(4-Chlorophenyl)thiazol-2-yl)acetonitrile (1.00 g,
4.26 mmol) and KtOBu (0.478 g, 4.26 mmol) were added and stirred
at 50 °C for 3 h. The solvent was removed. To the residue were added
2,6-diethylaniline (0.772 mL, 4.69 mmol) and AcOH (6.10 mL, 107
mmol) and sonicated to a homogeneous mixture. The reaction
mixture was stirred at 70 °C for 4 h, cooled to room temperature,
diluted with EtOAc, and washed with water. The organic layer was
dried, concentrated, and purified by column chromatography to afford
ethyl 5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-oxo-
2-propyl-1,6-dihydro-pyridine-3-carboxylate; LCMS: m/z (M + H)+ =
535.3.
Step 4−5: To a solution of ethyl 5-(4-(4-chlorophenyl)thiazol-2-
yl)-1-(2,6-diethylphenyl)-6-oxo-2-propyl-1,6-dihydropyridine-3-car-
boxylate (1.5 g, 2.8 mmol) in THF (10 mL) and MeOH (10 mL) was
added lithium hydroxide (0.470 g, 19.6 mmol). The reaction mixture
was stirred at 60 °C for 3 h. The solvent was removed by rotovap,
diluted with DCM, quenched with 1 N HCl, washed with brine (2 ×
50 mL), dried over MgSO4, and concentrated to afford the 5-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-oxo-2-propyl-1,6-
dihydropyridine-3-carboxylic acid; LCMS: m/z (M + H)+ = 507.0.
Without further purification, to the crude acid (1.00 g, 1.97 mmol)
were added 2-(3H-[1,2,3]triazolo[4,5-b]pyridin-3-yl)-1,1,3,3-tetrame-
thylisouronium hexafluorophosphate(V) (1.125 g, 2.96 mmol), DMF
(5 mL), N-ethyl-N-isopropylpropan-2-amine (0.689 mL, 3.94 mmol),
and piperazine (0.255 g, 2.96 mmol) (mixture became yellow). The
reaction mixture was stirred for 1 h at rt, diluted with water, extracted
with 3 × 10 mL of DCM, and washed with brine. The organic layer
was dried and concentrated. The crude mixture was diluted with
DMSO and purified by reverse-phase chromatography (Standard
Acidic Gradient Method) to afford as a TFA salt, 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(piperazine-1-car-
bonyl)-6-propylpyridin-2(1H)-one; LCMS: m/z (M + H)+ = 575.1;
1H NMR (400 MHz, DMSO-d6): δ 8.54 (d, J = 2.1 Hz, 1H), 8.18 (d,
Synthesis of Intermediates.
6,6-Dimethyldihydro-2H-pyran-2,4(3H)-dione (Ic). To NaH (1.92 g,
80 mmol) in anhydrous THF (200 mL) was added, at 0 °C, methyl
acetoacetate (9.28 g, 80 mmol) dropwise. After 10 min of stirring, n-
BuLi (32 mL, 2.5 M solution in hexanes, 80 mmol) was added
dropwise, and the orange solution was stirred at 0 °C for 10 more
min. Dry acetone (7.5 mL, 82 mmol) was added at once, and the
mixture was stirred for 10 min at 0 °C. NaOH (80 mL, 2.5 M solution
in water) was then added, and the mixture was stirred for 12 h at
room temperature, whereupon it was acidified (2.5 M HCl solution)
and extracted with ether (3 × 200 mL). The organic layer was washed
with brine and dried with Na2SO4. After filtration, the solvent was
evaporated with rotovap. The residue was dissolved in a minimum of
CH2Cl2 and precipitated with pentane as a brownish solid, yield
(62%) mp 126−127 °C. 1H NMR (400 MHz, CDCl3): 1.48 (s, 6H);
2.66 (s, 2H); 3.40 (s, 2H).
Method D: Ethyl 3-Oxo-4-(tetrahydrofuran-3-yl)butanoate. To a
solution of 2-(tetrahydrofuran-3-yl)acetic acid (1.00 g, 7.68 mmol) in
DCM (10 mL) were added DMAP (1.408 g, 11.53 mmol) and DCC
(2.378 g, 11.53 mmol) and then 2,2-dimethyl-1,3-dioxane-4,6-dione
(1.107 g, 7.68 mmol) was added and the mixture was stirred for 12 h
at room temperature. The insoluble urea was then removed by
filtration over Celite, and the solvent was evaporated under reduced
pressure. The crude product was redissolved in ethyl acetate and
washed with 1 M HCl. The organic phase was dried over Na2SO4,
filtered, and evaporated. The crude product was used without further
purification. The crude product was dissolved in ethanol (20 mL) and
refluxed for 6 h. The organic solvent was evaporated under reduced
pressure and purified by column chromatography to afford ethyl 3-
oxo-4-(tetrahydrofuran-3-yl) butanoate.
J = 2.0 Hz, 1H), 8.09 (d, J = 7.8 Hz, 2H), 7.49 (dd, J = 16.9, 7.7 Hz,
4H), 7.34 (d, J = 7.9 Hz, 2H), 3.63 (s, 1H), 3.55 (s, 1H), 3.28 (d, J =
4.1 Hz, 2H), 3.28 (s, 4H), 2.81 (s, 1H), 2.70 (s, 5H), 2.61 (s, 1H),
2.29 (dt, J = 15.3, 7.3 Hz, 4H), 2.14 (s, 4H), 1.27 (s, 2H), 1.07 (t, J =
7.4 Hz, 8H), 0.60 (t, J = 7.1 Hz, 4H); HRMS (ESI): m/z (M + H)+
calcd for C32H36ClN4O2S, 575.2242; found, 575.2223. Retention time
= 2.804 min.
Ethyl 3-Oxo-4-(tetrahydro-2H-pyran-4-yl)butanoate. This com-
pound was prepared using Method 14 using 2-(tetrahydro-2H-pyran-
4-yl)acetic acid to afford ethyl 3-oxo-4-(tetrahydro-2H-pyran-4-
yl)butanoate.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-iso-
propyl-5-(piperazine-1-carbonyl)pyridin-2(1H)-one (90). This com-
pound was prepared via Method 13 using methyl 4-methyl-3-
oxopentanoate in step 1 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-
1-(2,6-diethylphenyl)-6-isopropyl-5-(piperazine-1-carbonyl)pyridin-
1
2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ = 575.2; H NMR
tert-Butyl 3-(4-Ethoxy-2,4-dioxobutyl)pyrrolidine-1-carboxylate.
(400 MHz, DMSO-d6): δ 8.79 (s, 1H), 8.68 (s, 1H), 8.23 (d, J = 0.6
This compound was prepared using Method 14 using 2-(1-(tert-
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butoxycarbonyl)pyrrolidin-3-yl)acetic acid to afford tert-butyl 3-(4-
ethoxy-2,4-dioxobutyl)pyrrolidine-1-carboxylate.
2H), 3.52 (d, J = 29.4 Hz, 3H), 3.24 (s, 1H), 2.31 (d, J = 61.9 Hz,
4H), 1.67 (dd, J = 21.3, 1.1 Hz, 6H), 1.31 (s, 2H), 1.26−1.06 (m,
6H). Aliphatic region complicated significantly by amide rotamers;
HRMS (ESI): m/z (M + H)+ calcd for C33H36ClN4O2S, 587.2242;
found, 587.2243. Retention time = 2.781 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-6-(cyclopropylmethyl)-1-(2,6-
diethylphenyl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-one (93).
This compound was prepared using Method 13 using ethyl 4-
cyclopropyl-3-oxobutanoate in step 1 to afford 3-(4-(4-
chlorophenyl)thiazol-2-yl)-6-(cyclopropylmethyl)-1-(2,6-diethylphen-
yl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-one as a TFA salt.
1
LCMS: m/z (M + H)+ = 587.2; H NMR (400 MHz, DMSO-d6):
δ 8.79 (br s, 2H), 8.73 (s, 1H), 8.21 (s, 1H), 8.16−8.07 (m, 2H),
7.55−7.44 (m, 3H), 7.34 (d, J = 7.7 Hz, 2H), 4.07 (m, 1H), 3.74 (m,
1H), 3.51 (m, 3H), 3.12 (m, 3H), 2.35 (m, 2H), 2.12 (m, 5H), 1.07
(t, J = 7.5 Hz, 6H), 0.52−0.12 (m, 2H), −0.05 (m, 1H), −0.27 (m,
1H); HRMS (ESI): m/z (M + H)+ calcd for C26H28ClN14O,
587.2254; found, 587.2255. Retention time = 2.803 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-
methoxyethyl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-one (94).
This compound was prepared using Method 13 using methyl 5-
methoxy-3-oxopentanoate in step 1 to afford 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-methoxyethyl)-5-(piperazine-
1-carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ =
Method 15: 3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-6-(2-methylprop-1-en-1-yl)-5-(piperazine-1-carbonyl)-
pyridin-2(1H)-one (92). Steps 1−3: A mixture of 6,6-dimethyldihy-
dro-2H-pyran-2,4(3H)-dione (3.03 g, 21.30 mmol) and 1,1-
dimethoxy-N,N-dimethylmethanamine (2.83 mL, 21.30 mmol) was
stirred for 15 min at room temperature. The reaction mixture became
a yellow solid. To the mixture were added 2-propanol (50 mL), 2-(4-
(4-chlorophenyl)thiazol-2-yl)acetonitrile (5.00 g, 21.3 mmol), and
piperidine (8.4 mL, 85 mmol) and then sonicated to get a
homogeneous mixture. The mixture was stirred at 70 °C for 4 h.
The solvent was removed by rotovap. To the residue were added 2,6-
diethylaniline (3.86 mL, 23.4 mmol) and acetic acid (61.00 mL, 1065
mmol) and the reaction mixture was sonicated to dissolve solids. The
mixture was stirred at 70 °C for 4 h and cooled to room temperature
and diluted with DCM and washed with water, sat NaHCO3 solution,
and brine solution. The organic layer was dried over Na2SO4 and
concentrated. The crude product was purified by column chromatog-
raphy (10:90 EA/Hex to 100% EA) to afford the product, 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-7,7-dimethyl-7,8-di-
hydro-2H-pyrano[4,3-b]pyridine-2,5(1H)-dione; LCMS: m/z (M +
H)+ = 520.2.
Step 4: To a solution of 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-
diethylphenyl)-7,7-dimethyl-7,8-dihydro-1H-pyrano[4,3-b]pyridine-
2,5-dione (3.5 g, 6.74 mmol) in THF (25 mL) and MeOH (25 mL)
was added lithium hydroxide (1.13 g, 47.2 mmol) and the reaction
mixture was stirred at room temperature for 1 h. The solvent was
removed and diluted with DCM and quenched with acetic acid (2.70
mL, 47.2 mmol). The organic layer was washed several times with
brine and dried over Na2SO4 and concentrated to afford the crude 5-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-methyl-
prop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carboxylic acid; LCMS:
m/z (M + H)+ = 519.2. Yield ∼95%. The crude acid was used in the
next step without further purification.
1
591.2; H NMR (400 MHz, DMSO-d6): δ 8.74 (d, J = 0.5 Hz, 2H),
8.24 (d, J = 0.5 Hz, 1H), 8.18−8.10 (m, 2H), 7.58−7.47 (m, 3H),
7.39 (s, 1H), 7.37 (s, 1H), 4.04 (s, 1H), 3.85−3.43 (m, 3H), 3.16 (d,
J = 35.4 Hz, 6H), 3.02 (d, J = 0.6 Hz, 3H), 2.85 (s, 1H), 2.33 (t, J =
1.9 Hz, 2H), 2.17 (s, 2H), 1.11 (s, 7H). Aliphatic region complicated
significantly by amide rotamers; HRMS (ESI): m/z (M + H)+ calcd
for C32H36ClN4O3S, 591.2191; found, 591.2195. Retention time =
3.741 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(pi-
perazine-1-carbonyl)-6-(3,3,3-trifluoropropyl)pyridin-2(1H)-one
(95). This compound was prepared using Method 13 using ethyl
6,6,6-trifluoro-3-oxohexanoate in step 1 to afford 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(piperazine-1-car-
bonyl)-6-(3,3,3-trifluoropropyl)pyridin-2(1H)-one as a TFA salt.
1
LCMS: m/z (M + H)+ = 629.2; H NMR (400 MHz, DMSO-d6):
δ 8.77 (m, 3H), 8.24 (s, 1H), 8.16−8.08 (m, 2H), 7.55−7.47 (m,
3H), 7.38 (d, J = 7.7 Hz, 2H), 3.72 (br m, 5H), 3.17 (br m, 2H), 2.36
(dt, J = 15.1, 7.6 Hz, 2H), 2.02 (br m, 3H), 1.08 (t, J = 7.5 Hz, 6H);
HRMS (ESI): m/z (M + H)+ calcd for C32H33ClF3N4O2S, 629.1959;
found, 629.195. Retention time = 2.851 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(pi-
perazine-1-carbonyl)-6-((tetrahydrofuran-3-yl)methyl)pyridin-
2(1H)-one (96). This compound was prepared using Method 13 using
ethyl 3-oxo-4-(tetrahydrofuran-3-yl)butanoate in step 1 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(piperazine-
1-carbonyl)-6-((tetrahydrofuran-3-yl)methyl)pyridin-2(1H)-one as a
1
TFA salt. LCMS: m/z (M + H)+ = 617.2; H NMR (400 MHz,
DMSO-d6): δ 8.68 (s, 1H), 8.18 (s, 1H), 8.10−8.05 (m, 2H), 7.48−
7.41 (m, 3H), 7.31 (d, J = 7.7 Hz, 2H), 3.98 (s, 1H), 3.72 (s, 1H),
3.46 (d, J = 17.9 Hz, 2H), 3.07−2.95 (m, 6H), 2.57−2.49 (m, 1H),
2.16−1.90 (m, 6H), 1.71 (d, J = 21.7 Hz, 1H), 1.59 (d, J = 10.6 Hz,
2H), 1.38−135 (m, 1H), 1.02 (d, J = 9.1 Hz, 6H); HRMS (ESI): m/z
(M + H)+ calcd for C34H38ClN4O3S, 617.2348; found, 617.2332.
Retention time = 2.722 min.
Steps 5 and 6: To a solution of 5-(4-(4-chlorophenyl)thiazol-2-yl)-
1-(2,6-diethylphenyl)-2-(2-methylprop-1-en-1-yl)-6-oxo-1,6-dihydro-
pyridine-3-carboxylic acid (2.0 g, 3.85 mmol) were added HATU
(2.198 g, 5.78 mmol), DMF (volume: 10 mL), DIPEA (1.346 mL,
7.71 mmol), and piperazine (1.077 g, 5.78 mmol). The reaction
mixture was stirred for 1 h at rt, diluted with water, extracted with 3 ×
10 mL of DCM, and washed with brine. The organic layer was dried
and concentrated. The crude product (without further purification)
was diluted with DCM (10 mL) and TFA (10.39 mL, 135 mmol) and
stirred for 1 h at rt. The solvent was concentrated under vacuum, and
the crude mixture was diluted with DMSO and purified by reverse-
phase chromatography (Standard Acidic Gradient Method) to afford
as a TFA salt, 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphen-
yl)-6-(2-methylprop-1-en-1-yl)-5-(piperazine-1-carbonyl)pyridin-
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(pi-
perazine-1-carbonyl)-6-((tetrahydro-2H-pyran-4-yl)methyl)pyridin-
2(1H)-one (97). This compound was prepared using Method 13 using
ethyl 3-oxo-4-(tetrahydro-2H-pyran-4-yl)butanoate in step 1 to afford
3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(pipera-
zine-1-carbonyl)-6-((tetrahydro-2H-pyran-4-yl)methyl)pyridin-
1
2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ = 631.2; H NMR
(400 MHz, DMSO-d6): δ 8.67 (s, 1H), 8.19 (s, 1H), 8.08 (d, J = 8.6
Hz, 2H), 7.51−7.41 (m, 3H), 7.33 (d, J = 7.7 Hz, 2H), 4.00 (s, 1H),
3.67−3.60 (m, 3H), 2.95 (td, J = 11.6, 2.4 Hz, 2H), 2.37−2.23 (m,
2H), 2.22−1.98 (m, 4H), 1.22−0.88 (m, 16H); HRMS (ESI): m/z
(M + Na)+ calcd for C35H39ClN4NaO3S, 653.2324; found, 653.2336.
Retention time = 2.746 min.
1
2(1H)-one; LCMS: m/z (M + H)+ = 587.2; H NMR (400 MHz,
DMSO-d6): δ 8.91 (s, 1H), 8.08−8.02 (m, 2H), 7.95 (s, 1H), 7.53−
7.43 (m, 3H), 7.39−7.29 (m, 2H), 5.39 (s, 1H), 4.38 (s, 1H), 3.78 (s,
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3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(pi-
perazine-1-carbonyl)-6-(pyrrolidin-3-ylmethyl)pyridin-2(1H)-one
(98). This compound was prepared using Method 13 using tert-butyl
3-(4-ethoxy-2,4-dioxobutyl)pyrrolidine-1-carboxylate in step 1 fol-
lowed by Boc deprotection using TFA in DCM to afford 3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(piperazine-1-car-
bonyl)-6-(pyrrolidin-3-ylmethyl)pyridin-2(1H)-one as a TFA salt.
calcd for C36H39ClFN4O3, 629.2689; found, 629.2701. Retention time
= 2.889 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-
methylprop-1-en-1-yl)-5-(4,7-diazaspiro[2.5]octane-7-carbonyl)-
pyridin-2(1H)-one (103). This compound was prepared using
Method 15 using tert-butyl 4,7-diazaspiro[2.5]octane-4-carboxylate
in step 5 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-dieth-
ylphenyl)-6-(2-methylprop-1-en-1-yl)-5-(4,7-diazaspiro[2.5]octane-7-
carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ =
613.3; 1H NMR (400 MHz, DMSO-d6): δ 8.71 (s, 1H), 8.41 (s, 1H),
8.29 (d, J = 8.1 Hz, 2H), 7.83 (d, J = 8.2 Hz, 2H), 7.48−7.21 (m,
3H), 5.33 (s, 1H), 4.43−4.33 (m, 1H), 3.70−3.37 (m, 3H), 3.07−
2.90 (m, 2H), 2.71−2.59 (m, 2H), 2.44−1.90 (m, 4H), 1.58 (d, J =
10.3 Hz, 6H), 1.26−0.72 (m, 9H); HRMS (ESI): m/z (M + H)+
calcd for C35H38ClN4O2S, 613.2399; found, 613.2427. Retention time
= 2.85 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(3-
(hydroxymethyl)piperazine-1-carbonyl)-6-(2-methylprop-1-en-1-
yl)pyridin-2(1H)-one (104). This compound was prepared using
Method 15 using tert-butyl 2-(hydroxymethyl)piperazine-1-carbox-
ylate in step 5 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-
diethylphenyl)-5-(3-(hydroxymethyl)piperazine-1-carbonyl)-6-(2-
methylprop-1-en-1-yl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z
(M + H)+ = 617.2; 1H NMR (400 MHz, DMSO-d6): δ 8.73 (s, 1H),
8.25 (s, 1H), 8.09 (d, J = 8.5 Hz, 2H), 7.53 (d, J = 8.5 Hz, 2H), 7.43
(t, J = 7.7 Hz, 1H), 7.29 (dd, J = 20.5, 7.7 Hz, 2H), 5.29 (s, 1H),
4.63−4.53 (m, 1H), 3.73−3.39 (m, 3H), 3.21−2.63 (m, 2H), 2.44−
2.18 (m, 4H), 2.16−1.99 (m, 2H), 1.63−1.51 (m, 7H), 1.16−1.05
(m, 3H), 0.98 (t, J = 7.5 Hz, 3H); HRMS (ESI): m/z (M + H)+ calcd
for C34H38ClN4O3S, 617.2348; found, 617.2376. Retention time =
2.743 min.
1
LCMS: m/z (M + H)+ = 616.2; H NMR (400 MHz, DMSO-d6): δ
8.96 (br s, 2H), 8.74 (s, 1H), 8.54 (br s, 2H), 8.24 (s, 1H), 8.16−8.01
(m, 2H), 7.60−7.44 (m, 3H), 7.37 (d, J = 7.7 Hz, 2H), 4.19−2.56 (m,
10H), 2.44−1.94 (m, 5H), 1.63 (dd, J = 101.3, 45.9 Hz, 5H), 1.39−
1.15 (m, 1H), 1.10 (t, J = 7.5 Hz, 6H); HRMS (ESI): m/z (M + H)+
calcd for C29H34ClF3N9O, 616.2521; found, 616.2524. Retention time
= 2.321 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(3-
methylpiperazine-1-carbonyl)-6-(2-methylprop-1-en-1-yl)pyridin-
2(1H)-one (99). This compound was prepared using Method 15 using
tert-butyl 2-methylpiperazine-1-carboxylate in step 5 to afford 3-(4-
(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(3-methylpi-
perazine-1-carbonyl)-6-(2-methylprop-1-en-1-yl)pyridin-2(1H)-one
1
as a TFA salt. LCMS: m/z (M + H)+ = 601.1; H NMR (400 MHz,
DMSO-d6): δ 8.73 (d, J = 9.4 Hz, 1H), 8.25 (s, 1H), 8.09 (dd, J = 8.9,
2.3 Hz, 2H), 7.53 (dd, J = 8.7, 2.3 Hz, 2H), 7.43 (t, J = 7.7 Hz, 1H),
7.29 (dd, J = 22.5, 7.7 Hz, 2H), 5.30 (s, 1H), 4.55 (dd, J = 32.5, 13.8
Hz, 1H), 4.33−4.23 (m, 1H), 3.72−3.48 (m, 1H), 3.23−2.62 (m,
3H), 2.42−2.24 (m, 2H), 2.16−1.97 (m, 2H), 1.63−1.52 (m, 6H),
1.24 (dd, J = 12.0, 6.4 Hz, 1H), 1.11 (dt, J = 11.5, 7.3 Hz, 6H), 0.98
(t, J = 7.5 Hz, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C34H38ClN4O2S, 601.2399; found, 601.2395. Retention time = 2.805
min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(2-
methylpiperazine-1-carbonyl)-6-(2-methylprop-1-en-1-yl)pyridin-
2(1H)-one (100). This compound was prepared using Method 15
using tert-butyl 3-methylpiperazine-1-carboxylate in step 5 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(3-methyl-
piperazine-1-carbonyl)-6-(2-methylprop-1-en-1-yl)pyridin-2(1H)-one
4-(5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-
methylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)-
piperazin-2-one (105). This compound was prepared using Method
15 using tert-butyl 2-oxopiperazine-1-carboxylate in step 5 to afford 4-
(5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-meth-
ylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)piperazin-2-
1
as a TFA salt. LCMS: m/z (M + H)+ = 601.1; H NMR (400 MHz,
1
DMSO-d6): δ 8.70 (s, 1H), 8.25 (s, 1H), 8.13−8.05 (m, 2H), 7.53
(dd, J = 8.9, 2.3 Hz, 2H), 7.42 (t, J = 7.7 Hz, 1H), 7.35−7.21 (m,
2H), 5.28 (s, 1H), 4.94 (s, 1H), 3.59 (d, J = 14.1 Hz, 1H), 3.27−2.93
(m, 5H), 2.42−2.21 (m, 2H), 2.10 (dp, J = 26.2, 7.5 Hz, 2H), 1.63−
1.47 (m, 6H), 1.38−1.19 (m, 1H), 1.17−1.06 (m, 6H), 0.99 (t, J =
7.5 Hz, 3H); HRMS (ESI): m/z (M + H)+ calcd for C34H38ClN4O2S,
601.2399; found, 601.2388. Retention time = 2.824 min.
one as a TFA salt. LCMS: m/z (M + H)+ = 601.1; H NMR (400
MHz, DMSO-d6): δ 8.70 (d, J = 8.2 Hz, 1H), 8.24 (d, J = 1.8 Hz,
1H), 8.17−7.97 (m, 3H), 7.58−7.36 (m, 4H), 5.23 (s, 1H), 3.89−
3.79 (s, 2H), 3.26−2.95 (m, 4H), 2.41−2.00 (m, 4H), 1.61−1.42 (m,
7H), 1.20−0.86 (m, 6H); HRMS (ESI): m/z (M + H)+ calcd for
C33H34ClN4O3S, 601.2035; found, 601.2049. Retention time = 3.612
min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(3-
ethylpiperazine-1-carbonyl)-6-(2-methylprop-1-en-1-yl)pyridin-
2(1H)-one (101). This compound was prepared using Method 15
using tert-butyl 2-ethylpiperazine-1-carboxylate in step 5 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-5-(3-ethylpi-
perazine-1-carbonyl)-6-(2-methylprop-1-en-1-yl)pyridin-2(1H)-one
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-
methylprop-1-en-1-yl)-5-(3-(trifluoromethyl)piperazine-1-
carbonyl)pyridin-2(1H)-one (106). This compound was prepared
using Method 15 using tert-butyl 2-(trifluoromethyl)piperazine-1-
carboxylate in step 5 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-
(2,6-diethylphenyl)-6-(2-methylprop-1-en-1-yl)-5-(3-
(trifluoromethyl)piperazine-1-carbonyl)pyridin-2(1H)-one as a TFA
1
as a TFA salt. LCMS: m/z (M + H)+ = 615.1; H NMR (400 MHz,
1
DMSO-d6): δ 8.75 (s, 1H), 8.25 (s, 1H), 8.14−8.05 (m, 2H), 7.57−
7.50 (m, 2H), 7.47−7.40 (m, 1H), 7.37−7.22 (m, 2H), 5.29 (s, 1H),
4.67−4.52 (m, 1H), 3.72−3.64 (m, 1H), 3.23−3.05 (m, 2H), 3.01−
2.61 (m, 2H), 2.45−2.20 (m, 2H), 2.14−1.99 (m, 2H), 1.66−1.51
(m, 9H), 1.16−1.06 (m, 3H), 1.02−0.94 (m, 3H), 0.87−0.79 (m,
2H); HRMS (ESI): m/z (M + H)+ calcd for C35H40ClN4O2S,
615.2555; found, 615.2525. Retention time = 2.848 min.
salt. LCMS: m/z (M + H)+ = 655.2; H NMR (400 MHz, DMSO-
d6): δ 8.75 (s, 1H), 8.24 (s, 1H), 8.10 (dd, J = 9.1, 2.5 Hz, 2H), 7.57−
7.48 (m, 2H), 7.43 (td, J = 7.7, 4.6 Hz, 1H), 7.30 (dd, J = 18.6, 7.0
Hz, 2H), 5.25 (s, 1H), 4.52−4.44 (m, 1H), 4.15−3.98 (m, 1H),
3.23−2.56 (m, 5H), 2.38−2.17 (m, 2H), 2.16−1.99 (m, 2H), 1.56 (d,
J = 11.2 Hz, 6H), 1.16−0.91 (m, 6H); HRMS (ESI): m/z (M + H)+
calcd for C34H35ClF3N4O2S, 655.2116; found, 655.214. Retention
time = 3.952 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-
methylprop-1-en-1-yl)-5-(3-propylpiperazine-1-carbonyl)pyridin-
2(1H)-one (102). This compound was prepared using Method 15
using tert-butyl 2-propylpiperazine-1-carboxylate in step 5 to afford 3-
(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-methyl-
prop-1-en-1-yl)-5-(3-propylpiperazine-1-carbonyl)pyridin-2(1H)-one
4-(5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-
methylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)-
piperazine-2-carbonitrile (107). This compound was prepared using
Method 15 using tert-butyl 2-cyanopiperazine-1-carboxylate in step 5
to afford 4-(5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-
2-(2-methylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)-
1
as a TFA salt. LCMS: m/z (M + H)+ = 629.3; H NMR (400 MHz,
DMSO-d6): δ 8.75 (s, 1H), 8.25 (s, 1H), 8.16−8.05 (m, 2H), 7.53
(dt, J = 9.7, 2.9 Hz, 2H), 7.49−7.38 (m, 1H), 7.29 (dd, J = 22.4, 7.9
Hz, 2H), 5.28 (s, 1H), 4.66−4.31 (m, 2H), 3.72−3.67 (m, 1H),
3.23−2.94 (m, 2H), 2.89−2.52 (m, 2H), 2.43−2.19 (m, 2H), 2.15−
1.99 (m, 2H), 1.65−1.50 (m, 6H), 1.37 (d, J = 1.2 Hz, 1H),, 1.16−
1.05 (m, 4H), 1.04−0.82 (m, 8H); HRMS (ESI): m/z (M + H)+
piperazine-2-carbonitrile as a TFA salt. LCMS: m/z (M + H)+
=
1
612.2; H NMR (400 MHz, DMSO-d6): δ 8.67 (d, J = 8.6 Hz, 1H),
8.24 (s, 1H), 8.09 (dd, J = 8.3, 1.7 Hz, 2H), 7.58−7.48 (m, 2H), 7.42
(t, J = 7.6 Hz, 1H), 7.29 (dd, J = 17.7, 7.3 Hz, 2H), 5.24 (d, J = 8.0
Hz, 1H), 4.45−4.12 (m, 1H), 3.23−2.97 (m, 2H), 2.93−2.63 (m,
4H), 2.44−2.20 (m, 2H), 2.20−2.01 (m, 2H), 1.67−1.50 (m, 6H),
4941
https://doi.org/10.1021/acs.jmedchem.1c00019
J. Med. Chem. 2021, 64, 4913−4946

Journal of Medicinal Chemistry
pubs.acs.org/jmc
Article
1.11 (t, J = 12.8, 7.4, Hz, 3H), 1.00 (t, J = 7.4 Hz, 3H); HRMS (ESI):
m/z (M + H)+ calcd for C34H35ClN5O2S, 612.2195; found, 612.22.
Retention time = 3.776 min.
octane-3-carboxylate in step 5 to afford 5-(3,8-diazabicyclo[3.2.1]-
octane-8-carbonyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethyl-
phenyl)-6-(2-methylprop-1-en-1-yl)pyridin-2(1H)-one as a TFA salt.
1
4-(5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-
methylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)-
piperazine-2-carboxylic Acid (108). This compound was prepared
using Method 15 using 1-(tert-butyl) 2-methyl piperazine-1,2-
dicarboxylate in step 5 followed by ester hydrolysis using LiOH in
THF/MeOH and Boc deprotection using TFA in DCM to afford 4-
(5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-meth-
ylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)piperazine-2-
LCMS: m/z (M + H)+ = 613.2; H NMR (400 MHz, DMSO-d6): δ
8.22 (s, 1H), 8.08 (d, J = 8.3 Hz, 2H), 7.52 (d, J = 8.3 Hz, 2H), 7.41
(t, J = 7.7 Hz, 2H), 7.27 (dd, J = 13.8, 7.7 Hz, 2H), 5.24 (s, 1H),
3.98−3.92 (m, 2H), 3.25−3.05 (m, 4H), 2.78−2.53 (m, 4H), 2.37−
2.02 (m, 4H),1.90 (s, 3H), 1.55 (s, 3H), 1.04−0.97 (m, 6H); HRMS
(ESI): m/z (M + H)+ calcd for C35H38ClN4O2S, 613.2399; found,
613.2389. Retention time = 2.798 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-6-(2-methylprop-1-en-1-yl)-1-
phenyl-5-(piperazine-1-carbonyl)pyridin-2(1H)-one (113). This
compound was prepared using Method 15 using aniline in step 3
to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-6-(2-methylprop-1-en-1-
yl)-1-phenyl-5-(piperazine-1-carbonyl)pyridin-2(1H)-one as a TFA
1
carboxylic acid as a TFA salt. LCMS: m/z (M + H)+ = 631.1; H
NMR (400 MHz, DMSO-d6): δ 8.75 (s, 1H), 8.25 (s, 1H), 8.09 (dd, J
= 8.2, 1.3 Hz, 2H), 7.53 (dd, J = 8.6, 2.3 Hz, 2H), 7.43 (td, J = 7.7, 5.6
Hz, 1H), 7.36−7.18 (m, 2H), 5.28 (s, 1H), 4.58−4.48 (m, 1H),
4.20−4.04 (m, 1H), 3.87−3.57 (m, 1H), 3.12−2.62 (m, 2H), 2.44−
2.17 (m, 2H), 2.20−1.99 (m, 2H), 1.63−1.49 (m, 6H), 1.24−1.05
(m, 3H), 1.03−0.94 (m, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C27H28Cl N14O3, 631.214; found, 631.2151. Retention time = 3.038
min.
4-(5-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-
methylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)-
piperazine-2-carboxamide (109). This compound was prepared
using Method 15 using piperazine-2-carboxamide in step 5 to afford
4-(5-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-2-(2-
methylprop-1-en-1-yl)-6-oxo-1,6-dihydropyridine-3-carbonyl)-
piperazine-2-carboxamide as a TFA salt. LCMS: m/z (M + H)+ =
630.3; 1H NMR (400 MHz, DMSO-d6): δ 8.76 (s, 1H), 8.26 (s, 1H),
8.09 (dd, J = 8.0, 6.0 Hz, 2H), 7.53 (dd, J = 8.0, 6.2 Hz, 2H), 7.43 (t, J
= 7.7 Hz, 1H), 7.37−7.20 (m, 2H), 5.29 (d, J = 9.5 Hz, 1H), 4.72−
4.55 (m, 1H), 4.02−3.72 (m, 1H), 3.66−3.54 (m, 1H), 3.17−2.99
(m, 2H), 2.82 (t, J = 13.0 Hz, 1H), 2.68−2.62 (m, 1H), 2.42−2.22
(m, 2H), 2.15−1.99 (m, 2H), 1.67−1.50 (m, 6H), 1.11 (t, J = 7.5 Hz,
3H), 1.05−0.91 (m, 3H); HRMS (ESI): m/z (M + H)+ calcd for
C34H34ClF5N3O, 630.2305; found, 630.2311. Retention time = 2.753
min.
1
salt. LCMS: m/z (M + H)+ = 531.2; H NMR (400 MHz, DMSO-
d6): δ 8.82 (s, 1H), 8.06−8.01 (m, 2H), 7.93 (d, J = 1.8 Hz, 1H),
7.61−7.49 (m, 3H), 7.48−7.42 (m, 2H), 7.37 (s, 1H), 7.19 (s, 1H),
5.59 (s, 1H), 4.25 (s, 2H), 3.84 (s, 2H), 3.64 (d, J = 18.3 Hz, 2H),
3.14 (s, 2H), 1.63 (dd, J = 9.4, 1.1 Hz, 6H). Aliphatic region
complicated significantly by amide rotamers; HRMS (ESI): m/z (M +
H)+ calcd for C29H28ClN4O2S, 531.1616; found, 531.1631. Retention
time = 2.583 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-ethylphenyl)-6-(2-meth-
ylprop-1-en-1-yl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-one
(114). This compound was prepared using Method 15 using 2-
ethylaniline in step 3 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-
(2-ethylphenyl)-6-(2-methylprop-1-en-1-yl)-5-(piperazine-1-
carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ =
1
559.2; H NMR (400 MHz, DMSO-d6): δ 8.86 (s, 1H), 8.04 (d, J =
8.7 Hz, 2H), 7.94 (s, 1H), 7.53−7.47 (m, 2H), 7.45 (d, J = 8.6 Hz,
2H), 7.44−7.00 (m, 2H), 5.62−5.42 (m, 1H), 4.35−4.25 (m, 2H),
3.90−3.50 (m, 4H), 3.35−3.10 (m, 2H), 2.50−2.25 (m, 2H), 1.67−
1.57 (m, 6H), 1.25−1.05 (m, 3H). Aliphatic region complicated
significantly by amide rotamers; HRMS (ESI): m/z (M + H)+ calcd
for C31H32ClN4O2S, 559.1929; found, 559.1937. Retention time =
2.675 min.
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-
methylprop-1-en-1-yl)-5-(2,6-diazaspiro[3.3]heptane-2-carbonyl)-
pyridin-2(1H)-one (110). This compound was prepared using
Method 15 using tert-butyl 2,6-diazaspiro[3.3]heptane-2-carboxylate
in step 5 to afford 3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-dieth-
ylphenyl)-6-(2-methylprop-1-en-1-yl)-5-(2,6-diazaspiro[3.3]heptane-
2-carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z (M + H)+ =
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-ethyl-6-methylphenyl)-6-
(2-methylprop-1-en-1-yl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-
one (115). This compound was prepared using Method 15 using 2-
ethyl-6-methylaniline in step 3 to afford 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-1-(2-ethyl-6-methylphenyl)-6-(2-methylprop-1-en-1-yl)-
5-(piperazine-1-carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS:
1
1
m/z (M + H)+ = 533.2; H NMR (400 MHz, DMSO-d6): δ 8.95 (s,
599.2; H NMR (400 MHz, DMSO-d6): δ 8.69 (d, J = 4.2 Hz, 1H),
8.23 (d, J = 8.1 Hz, 1H), 8.07 (dd, J = 8.7, 2.3 Hz, 2H), 7.56−7.49
(m, 2H), 7.42 (t, J = 7.7 Hz, 1H), 7.29 (d, J = 7.6 Hz, 2H), 5.30 (s,
1H), 4.08 (t, J = 11.4 Hz, 4H), 2.70−2.59 (m, 2H), 2.24−2.09 (m,
6H), 1.58 (s, 6H), 1.08−1.02 (m, 6H). HRMS (ESI): m/z (M + H)+
calcd for C34H36ClN4O2S, 599.2242; found, 599.225. Retention time
= 2.749 min.
2H), 8.71 (d, J = 6.5 Hz, 1H), 8.22 (s, 1H), 8.12 (d, J = 8.6 Hz, 2H),
7.52 (t, J = 8.4 Hz, 2H), 7.43 (t, J = 7.6 Hz, 1H), 7.33 (dd, J = 15.7,
8.1 Hz, 2H), 3.57 (d, J = 87.5 Hz, 4H), 3.16 (t, J = 47.1 Hz, 4H), 2.20
(t, J = 39.9 Hz, 1H), 1.98 (s, 3H), 1.90 (s, 3H), 1.08 (t, J = 7.5 Hz,
3H). Aliphatic region complicated significantly by amide rotamers;
HRMS (ESI): m/z (M + H)+ calcd for C29H30ClN4O2S, 533.1773;
found, 533.1792. Retention time = 2.6 min.
1-(2-Chloro-6-ethylphenyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-6-
(2-methylprop-1-en-1-yl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-
one (116). This compound was prepared using Method 15 using 2-
chloro-6-ethylaniline in step 3 to afford 1-(2-chloro-6-ethylphenyl)-3-
(4-(4-chlorophenyl)thiazol-2-yl)-6-(2-methylprop-1-en-1-yl)-5-(pi-
perazine-1-carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS: m/z
(M + H)+ = 593.2; 1H NMR (400 MHz, DMSO-d6): δ 8.88 (s, 1H),
8.03 (d, J = 8.7 Hz, 2H), 7.94 (s, 1H), 7.55−7.39 (m, 5H), 5.55−5.35
(m, 1H), 4.40−4.20 (m, 1H), 3.85−3.70 (m, 1H), 3.60−3.45 (m,
2H), 3.35−3.10 (m, 4H), 2.60−2.25 (m, 2H), 1.74−1.63 (m, 6H),
1.30−1.05 (m, 3H). Aliphatic region complicated significantly by
amide rotamers; HRMS (ESI): m/z (M + H)+ calcd for
C31H31Cl2N4O2S, 593.1539; found, 593.1528. Retention time =
4.187 min.
5-((1R,5S)-3,8-Diazabicyclo[3.2.1]octane-3-carbonyl)-3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-methylprop-
1-en-1-yl)pyridin-2(1H)-one (111). This compound was prepared
using Method 15 using tert-butyl (1R,5S)-3,8-diazabicyclo[3.2.1]-
octane-8-carboxylate in step 5 to afford 5-((1R,5S)-3,8-diazabicyclo-
[3.2.1]octane-3-carbonyl)-3-(4-(4-chlorophenyl)thiazol-2-yl)-1-(2,6-
diethylphenyl)-6-(2-methylprop-1-en-1-yl)pyridin-2(1H)-one as a
1
TFA salt. LCMS: m/z (M + H)+ = 613.2; H NMR (400 MHz,
DMSO-d6): δ 8.73 (s, 1H), 8.24 (s, 1H), 8.15−8.04 (m, 2H), 7.58−
7.48 (m, 2H), 7.42 (t, J = 7.7 Hz, 1H), 7.29 (dd, J = 26.3, 7.7 Hz,
2H), 5.23 (s, 1H), 4.44 (d, J = 14.0 Hz, 1H), 4.14−3.86 (m, 2H),
3.61−3.34 (m, 2H), 2.96 (d, J = 14.0 Hz, 1H), 2.65 (p, J = 1.9 Hz,
1H), 2.44−2.27 (m, 2H), 2.15−1.97 (m, 2H), 1.96−1.71 (m, 3H),
1.55 (dd, J = 10.4, 1.3 Hz, 6H), 1.14 (t, J = 7.7 Hz, 3H), 0.96 (t, J =
7.5 Hz, 3H); HRMS (ESI): m/z (M + Na)+ calcd, for
C35H37ClN4NaO2S, 635.2218; found, 635.2206. Retention time =
2.823 min.
5-(3,8-Diazabicyclo[3.2.1]octane-8-carbonyl)-3-(4-(4-
chlorophenyl)thiazol-2-yl)-1-(2,6-diethylphenyl)-6-(2-methylprop-
1-en-1-yl)pyridin-2(1H)-one (112). This compound was prepared
using Method 15 using tert-butyl (1R,5S)-3,8-diazabicyclo[3.2.1]-
3-(4-(4-Chlorophenyl)thiazol-2-yl)-1-(2-ethyl-5-methylphenyl)-6-
(2-methylprop-1-en-1-yl)-5-(piperazine-1-carbonyl)pyridin-2(1H)-
one (117). This compound was prepared using Method 15 using 2-
ethyl-5-methylaniline in step 3 to afford 3-(4-(4-chlorophenyl)-
thiazol-2-yl)-1-(2-ethyl-5-methylphenyl)-6-(2-methylprop-1-en-1-yl)-
5-(piperazine-1-carbonyl)pyridin-2(1H)-one as a TFA salt. LCMS:
4942
https://doi.org/10.1021/acs.jmedchem.1c00019
J. Med. Chem. 2021, 64, 4913−4946