Synthesis and structure-activity relationship of dihydrobenzofuran derivatives as novel human GPR119 agonists

Article abstract of DOI:10.1016/j.bmcl.2014.03.096

Through appropriate medicinal chemistry design tactics and computer-assisted conformational modeling, the initial lead A was evolved into a series of dihydrobenzofuran derivatives 3 as potent GPR119 agonists. This Letter describes the optimization of general structure 3, including the substituent(s) on dihydrobenzofuran, the R¹ attachment on right-hand piperidine nitrogen, and the left-hand piperidine/piperazine and its attachment R². The efforts led to the identification of compounds 13c and 24 as potent human GPR119 modulators with favorable metabolic stability, ion channel activity, and PXR profiles.

Full text of DOI:10.1016/j.bmcl.2014.03.096

Bioorganic & Medicinal Chemistry Letters xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry Letters
journal homepage: www.elsevier.com/locate/bmcl
Synthesis and structure–activity relationship of dihydrobenzofuran
derivatives as novel human GPR119 agonists
a
a
b
c
Xiang-Yang Ye a, , Christian L. Morales , Ying Wang , Karen A. Rossi , Sarah E. Malmstrom ,
Mojgan Abousleiman c, Larisa Sereda e, Atsu Apedo d, Jeffrey A. Robl a, Keith J. Miller e, John Krupinski e,
Dean A. Wacker a
⇑
a Department of Chemistry, Research & Development, Bristol-Myers Squibb Co., PO Box 5400, Princeton, NJ 08543, United States
b CADD, Research & Development, Bristol-Myers Squibb Co., PO Box 5400, Princeton, NJ 08543, United States
c Leads Discovery and Optimization, Research & Development, Bristol-Myers Squibb Co., PO Box 5400, Princeton, NJ 08543, United States
d Bioanalytical and Discovery Analytical Sciences, Research & Development, Bristol-Myers Squibb Co., PO Box 5400, Princeton, NJ 08543, United States
e Department of Biology, Research & Development, Bristol-Myers Squibb Co., PO Box 5400, Princeton, NJ 08543, United States
a r t i c l e i n f o
a b s t r a c t
Article history:
Through appropriate medicinal chemistry design tactics and computer-assisted conformational model-
ing, the initial lead A was evolved into a series of dihydrobenzofuran derivatives 3 as potent GPR119 ago-
nists. This Letter describes the optimization of general structure 3, including the substituent(s) on
dihydrobenzofuran, the R1 attachment on right-hand piperidine nitrogen, and the left-hand piperidine/
piperazine and its attachment R2. The efforts led to the identification of compounds 13c and 24 as potent
human GPR119 modulators with favorable metabolic stability, ion channel activity, and PXR profiles.
Ó 2014 Elsevier Ltd. All rights reserved.
Received 6 March 2014
Revised 26 March 2014
Accepted 28 March 2014
Available online xxxx
Keywords:
GPR119
Agonist
Type 2 diabetes
Type 2 diabetes mellitus (T2DM) is a chronic disease character-
ized by elevated blood glucose levels in the context of insulin resis-
tance and relative insulin deficiency. Impairments in both insulin
production and insulin sensitivity result in a chronic demand for
greater b-cell insulin production, which ultimately leads to the
gradual loss of pancreatic b-cell function as diabetes progresses.
Currently we are in an unprecedented era of explosive increases
of diabetes population, from approximately 285 million in 2010
to a projection of over 330 million diabetics worldwide by 2030.1
Despite current available treatments such as insulin, metformin,
thiazolidinones (TZDs), sulfonylurea derivatives, and dipeptidyl
peptidase 4 (DPP-IV) inhibitors, glycemic control represents a sig-
nificant unmet medical need, due to both the increasing patient
population and the ineffectiveness of the above antidiabetic agents
over years of treatment.
glucose-dependent insulin secretion from pancreatic b-cells and
increased release of the gut hormones such as GLP-1 (glucagon-like
peptide 1), GIP (glucose-dependent insulinotropic peptide) and
PYY (polypeptide YY) from enteroendocrine cells. This dual mech-
anism of action might produce favorable effects on glucose homeo-
stasis and b-cell preservation, along with other beneficial effects
such as reduced food intake and body weight.2,3 Scientific evidence
has been published by various laboratories demonstrating the
capability of small synthetic GPR119 agonists to lower glucose in
a variety of animal models.4 In addition, Overton et al. reported
that OEA (oleoylethanolamide, an endogenous agonist of
GPR119) and PSN632408 (a synthetic GPR119 agonist) reduced
body weight, white adipose tissue depots, and food intake in
diet-induced obese rats.5 Several pharmaceutical companies have
entered clinical trials with small molecule GPR119 agonists. This
includes: Johnson & Johnson/Arena JNJ-38431055,6a,b Metabolex/
Sanofi-Aventis MBX-2982,6b,c GlaxoSmithKline GSK1292263,6b,d
and Astellas Pharma PSN8216b,e (Fig. 1). The available clinical data
demonstrate the ability of GPR119 agonists to promote incretin re-
lease and reduce postprandial glucose excursion.7 All these results
have made GPR119 an attractive drug target for treating diabetes
and possibly obesity, with a low propensity to cause hypoglycemia.
As part of our discovery efforts searching for small molecule
GPR119 agonists, we analyzed active pharmacophores of known
G protein-coupled receptor 119 (GPR119) is a rhodopsin-like,
class A Gs-coupled GPCR, which is predominately expressed in
human pancreatic b-cells, where it mediates insulin secretion,
and in gastrointestinal L-cells, where it mediates GLP-1 release.
The activation of GPR119 increases the intracellular accumulation
of cyclic adenosine monophosphate (cAMP), leading to enhanced
⇑
Corresponding author. Tel.: +1 (609) 818 4130; fax: +1 (609) 818 3460.
E-mail address: xiang-yang.ye@bms.com (X.-Y. Ye).
http://dx.doi.org/10.1016/j.bmcl.2014.03.096
0960-894X/Ó 2014 Elsevier Ltd. All rights reserved.
Please cite this article in press as: Ye, X.-Y.; et al. Bioorg. Med. Chem. Lett. (2014), http://dx.doi.org/10.1016/j.bmcl.2014.03.096

2
X.-Y. Ye et al. / Bioorg. Med. Chem. Lett. xxx (2014) xxx–xxx
S
O
O
O
O
S
N
N
N
N
N
N
N
N
N
O
N
N
N
H
O
N
O
Et
OMe
MBX-2982
JNJ-38431055
(APD597)
O
S
O
O
N
N
N
O
O
N
N
N
O
N
O
GSK1292263
N
PSN632408
Figure 1. Some clinically advanced GPR119 agonists.
agonists from the literature8,9 and found that para-methylsulfonyl-
phenyl and substituted 4-hydroxyl piperidine are common frag-
ments. In our initial efforts, we linked these two fragments via
the 1,4-positions of a phenyl group and generated a set of com-
pounds of general structure A (Scheme 1). These compounds
exhibited moderate GPR119 agonism activity in vitro.10 In an effort
to improve potency, we focused on a strategy that conformational-
ly constrained the molecule, exemplified by the spiro dihydroben-
zofuran analogs 1. Unfortunately, several analogs of 1 showed no
GPR119 agonism activity. Conformational searches of several
molecules were performed using MacroModel (Schrödinger, LLC,
New York, NY, 2008) with the OPLS2005 force field, followed by
energetic analysis of low energy structures using Jaguar DFT
B3LYP/6-31G⁄⁄ (Schrödinger, LLC, New York, NY, 2008). A low
energy conformation of literature compound APD5976a,8 was used
as the basis for a pharmacophore and low energy conformations of
our compounds were matched to the pharmacophore using Phase
(Schrödinger, LLC, New York, NY, 2008). The analogs clearly
demonstrated that compound 1 was not only too short to match
the desired pharmacophore of APD597, but also possessed a
completely different piperidine ring orientation (Fig. 2). This led
us to conceive a slightly longer version of the dihydrobenzofuran,
2, by simple insertion of a bond between dihydrobenzofuran and
piperidine. This change simultaneously offers greater molecular
length and the appropriate orientation of the piperidine ring via
release of the spiro fusion. The modeling results suggest a better
overlay of compound 2 with APD597 than compound 1 (Fig. 2).
Therefore, a set of analogs of compound 2 was synthesized. To
our delight, moderate GPR119 activity was regained. In order to
Figure 2. Overlay of lowest energy conformations of 1 analog (in yellow), 2 analog
(in magenta), and APD597 (in cyan).
improve the in vitro activity of 2, the left-hand phenyl was re-
placed with piperidinyl or piperazinyl. To our surprise, such mod-
ifications resulted in significant improvement of in vitro potency,
which led to the evolution of the dihydrobenzofuran series to the
general structure 3 (Scheme 1).
We developed a general route to access dihydrobenzofuran ana-
logs 4 as described in Scheme 2. Selective lithiation at the a-position
of the commercially available benzofuran 5 was achieved using n-
BuLi at ꢀ78 °C. The resulting benzofuran-2-yllithium reacted with
tert-butyl 4-oxopiperidine-1-carboxylate to afford 6. Attempts to
convert 6 to 8 using Pd catalyzed hydrogenation in a single step
did not prove to be successful.11 Therefore, a two-step approach
was adopted. Treatment of 6 with Et3SiH and TFA under reflux con-
ditions resulted in the removal of the benzylic hydroxyl group and
the deprotection of the Boc group, yielding 7. The amine functional
group was then reprotected with Boc, and the subsequent Pd-cata-
lyzed hydrogenation afforded 8. Selective bromination at the posi-
tion para- to the oxygen group of dihydrofuran 8 afforded 9 in
high yield. The Boc-protecting group was removed under acidic
insert a bond
molecule extention
conformation
constrain
R1
R1
R2
N
N
R2
O
O
R3
R3
1
A
inactive GPR119 agonists
active GPR119 agonists
R1
N
R1
left side aryl
replacement
X
N
R2
N
R2
O
O
R3
R3
3
2
potency improved
active GPR119 agonists
Scheme 1. Evolution of dihydrofuran chemotype.
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X.-Y. Ye et al. / Bioorg. Med. Chem. Lett. xxx (2014) xxx–xxx
3
HO
a
b
c
NH
N
Boc
O
O
O
5
6
7
Br
d
e,f
Boc
Boc
N
N
O
O
8
9
O
O
S
N
Br
g,e,h
R1
N
R1
N
O
O
10
4
Scheme 2. Synthesis of dihydrobenzofuran analogs 4. Reagents and conditions: (a) n-BuLi, THF, ꢀ78 °C, 20 min, then tert-butyl 4-oxopiperidine-1-carboxylate, ꢀ78 °C to
ꢀ40 °C (85–92%); (b) Et3SiH (4 equiv), TFA, CH2Cl2, 40 °C (100%); (c) (i) Boc2O, THF–H2O, K2CO3; (ii) 10% Pd–C, EtOH, H2 (55 psi) (87%); (d) NBS, MeOH, 0 °C to rt (85–95%); (e)
4 M HCl in dioxane, MeOH, rt (100%); (f) conditions vary depending on different functional group R1. When reacting with chloroformates, THF–H2O with Na2CO3, rt; when
reacting with sulfonyl chlorides, CH2Cl2, Et3N, 0 °C to rt; when reacting with substituted 2-chloropyrimidines or substituted 2-iodopyridines, DMF, K2CO3, 90 °C; when
reacting with aldehydes (reductive amination), MeOH, NaCNBH3; (g) tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate,
Pd(PPh3)4, K2CO3, dioxane–H2O, 100 °C, overnight (80–85%); (h) n-PrSO2-Cl, Et3N, CH2Cl2, 0 °C to rt (80–90%).
Table 1
Table 2
SAR of R1 substituents on the piperidine
SAR of the left-hand dehydropiperidine and its replacements
Compd12 R1
Human GPR119 cell line
% Remainingb
R4
N
a
N
EC50 (nM)
Emax (%)
Hu
Mu
O
N
4a
4b
521
88
NTc
NT
11
O
S
Compd R4
Human GPR119 cell line
% Remainingb
103
61
43
10
12
a
EC50 (nM)
Emax (%)
Hu
Mu
O
O
O
O
O
4c
1003
NT
NT
S
11a
541
53
NTc
NT
O
4d
4e
4f
51
78
14
56
88
NT
48
58
NT
45
70
F
S
O
N
O
O
O
O
Cl
N
4i
11b
11c
82
544
386
107
74
71
82
70
58
44
52
N
N
CF3
118
O
N
N
S
S
N
N
4g
4h
4i
67
34
82
85
99
58
47
71
3
N
N
O
46
58
CF3
N
43
N
N
107
a
EC50 refers to cAMP assay in human GPR119 cell line.
Represents percentage of compound remaining after incubation in human or
mouse microsomes after a 10-min incubation period.
b
EC50 refers to cAMP assay in human GPR119 cell line.13,14
Represents percentage of compound remaining after incubation in human or
a
b
c
NT = not tested.
mouse microsomes after a 10-min incubation period.
c
NT = not tested.
activity (521 nM), as do the carbamates (4b and 4d) and the sulfon-
amide (4c, much weaker agonism activity with Emax of 43%).
Pyrimidine and pyridine analogs (4e–4i) have better in vitro po-
tency, as indicated by their reasonable EC50 numbers and the over-
all higher Emax. For example, 5-trifluoromethylpyrimidine (4f)
shows the best potency in vitro (14 nM), but its extremely poor
aqueous solubility precluded it from further testing. 5-Chloropyr-
imidine (4e) and 5-(n-propyl)pyrimidine (4i) are equally potent
(78 vs 82 nM), but surprisingly, 5-(n-propyl)pyrimidine (4i) has
better stability in both human and mouse liver microsomes.
conditions and the resulting amine was then reacted with various
reagents (such as aldehydes, chloroformates, sulfonyl chlorides,
and 2-chloropyrimidines) under various conditions to form com-
pound 10. The synthesis of compound 4 from compound 10 was
achieved in three steps following the standard reaction sequence
of Suzuki coupling, deprotection, and sulfonamide formation.
To explore the SAR of the nitrogen attachment in the right-hand
piperidine (Table 1), the n-propyl sulfonamide was used as the
standard left-hand substitution. The basic amine 4a has moderate
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X.-Y. Ye et al. / Bioorg. Med. Chem. Lett. xxx (2014) xxx–xxx
O
O
S
N
a
N
N
11c
N
O
4i
Boc
N
Br
b
N
N
N
N
N
N
O
N
O
10i
12
O
O
S
N
c,d
N
N
N
O
N
11b
Scheme 3. Synthesis of dihydrobenzofuran analogs 11b and 11c. Reagents and conditions: (a) 10% Pd–C, EtOAc, room temperature, H2 (1 atm), 80%; (b) tert-butyl piperazine-
1-carboxylate, KOBu-t, Pd2(dba)3 (0.06 equiv), BINAP (0.02 equiv), toluene, 80 °C, 12 h (90%); (c) 4 M HCl in dioxane, MeOH, rt (100%); (d) n-PrSO2Cl, Et3N, CH2Cl2, 0 °C to rt
(80–90%).
OH
H
H
CHO
O
H
H
CHO
OH
c
b
a
O
O
R2
Si
R2
R1
16
R2
R1
R2
R1
17
R1
14
15
R1 and R2 = F or H
Scheme 2
13a-c
O
d
e
Br
N
O
N
Boc
Mg
OH
20
Br
Br
18
19
Scheme 2
O
13d
N
Boc
O
21
Scheme 4. Synthesis of dihydrobenzofuran analogs 13a–d. Reagents and conditions: (a) K2CO3, NaI, TMSCH2Cl, DMF, 65 °C, 100%; (b) CsF (3 equiv), DMF, 95 °C, 3 days, 82%
yield; (c) thionyl chloride (10 equiv), pyridine, 0 °C to rt, 17–60% yield; (d) ether, reflux, then ketone, rt, 19 h, 33% yield; (e) Pd(OAc)2, (S)-BINAP, K2CO3, toluene, 110 °C, 97%
yield.
Besides poor rodent microsomal stability (only 3% remaining), the
5-cyclopropylpyrimidine analog 4g (EC50 67 nM, Emax 85%) also
suffers from glutathione adduct formation due to the cyclopropyl
ring opening, precluding it from further consideration.
Based on the results from Tables 1 and 2, we decided to explore
the effects of substitution on the dihydrobenzofuran core. Scheme 4
describes the synthesis of the key fluorinated benzofuran interme-
diates 17, utilized for the synthesis of 13a–c. Commercially avail-
able substituted 2-hydroxybenzaldehydes 14 were reacted with
chloromethyl trimethylsilane in the presence of K2CO3 and NaI to
afford alkylation products 15, which were cyclized to 16 upon
heating with KF. Further dehydration of compounds 16 in thionyl
chloride/pyridine afforded substituted benzofurans 17, which were
transformed into 13a–c using the reactions described in Scheme 2.
In addition, compound 13d was designed and synthesized to block
the known metabolic soft spot at the 2-position of the dihydroben-
zofuran ring (using methyl group to replace hydrogen). To synthe-
size it, ortho-bromo benzyl magnesium bromide, generated in situ
from the corresponding bromide 18 and Mg in ether under reflux,
reacted with ketone 19 to afford the adduct 20. The intramolecular
Based on the results of Table 1, compound 4i appeared to have
the best overall profile, so our efforts were then devoted to using
5-(n-propyl)pyrimidine as the right-hand nitrogen attachment to
optimize the R4 group of 11 (Table 2). Analog 11a was synthesized
using the reaction conditions from Scheme 2, while analogs 11b
and 11c were synthesized using the conditions described in
Scheme 3. We quickly surveyed a set of R4 as piperidine replace-
ments (Table 2). Interestingly, 2-fluoro-4-methylsulfonylphenyl
analog (11a) is much less active than 4i, opposite to what have
been observed in our other chemotypes. Other close analogs of
4i, such as piperazine analog (11b) and saturated piperidine analog
(11c), are also less potent against the human GPR119 receptor.
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X.-Y. Ye et al. / Bioorg. Med. Chem. Lett. xxx (2014) xxx–xxx
5
Table 3
O-arylation of 20 was performed with a palladium complex to af-
ford dihydrobenzofuran 21 in high yield, which was further con-
verted to 13d using procedures described in Scheme 2.
SAR of dihydrobenzofuran core
O
O
S
Table 3 details the SAR of the dihydrobenzofuran core. Fluorine
was incorporated in the dihydrobenzofuran core at either 4-posi-
tion (13a) or 7-position (13b), or at both the 4- and 7-positions
(13c), in order to examine the substituent effect. 7-fluoro analog
13b showed comparable in vitro potency and a slight improvement
in liver microsomal stability than the corresponding unsubstituted
analog 4i. Interestingly, 4-fluoro analog 13a and 4,7-di-fluoro ana-
log 13c exhibited a remarkable enhancement of in vitro potency (5
and 2 nM vs 82 nM of 4i), suggesting an important interaction be-
tween the fluoro group at 4-position and the receptor. Both 13a
and 13c showed comparable metabolic stability as their parent
4i. Furthermore, compound 13d exhibited a slight improvement
of in vitro potency but had no improvement in metabolic stability
versus 4i, suggesting that blocking the 2-position of the dihydro-
benzofuran core did not produce a favorable metabolic stability
profile as projected.
N
N
N
N
13
Human GPR119 cell line
% Remainingb
a
Compd
4i
EC50 (nM)
Emax (%)
Hu
71
87
Mu
82
5
107
58
O
F
F
13a
123
78
O
O
Upon further profiling, compounds 13a and 13c were found to
exhibit most of the characteristics desirable for an effective
GPR119 agonist, including GPR119 in vitro potency, liver micro-
somal stability, high PAMPA permeability, low PXR transactivation,
weak CYP inhibition, etc. The most significant issue for this chem-
13b
62
93
97
74
F
otype was the poor aqueous solubility (generally <1 lg/mL at pH
6.5). We envisioned that a prodrug strategy might solve this issue.
After surveying several polar functional groups such as –OH and –
NH2 at the various positions of the molecule, we found that an –OH
group in the sulfonamide side chain was best suited for retention
of in vitro potency.
Table 4 shows the SAR of the hydroxyl sulfonamide analogs in
three different dihydrobenzofuran cores: I, II, and III. In general,
both primary and tertiary alcohols are active in vitro, with minimal
potency differences due to the length of the side chain. Compound
24 stands out as the analog of interest with potent human GPR119
13c
13d
2
119
48
78
68
80
52
O
O
F
Me
70
a
EC50 refers to cAMP assay in human GPR119 cell line.
Represents percentage of compound remaining after incubation in human or
mouse microsomes after a 10-min incubation period.
b
Table 4
SAR of dihydrobenzofuran analogs bearing hydroxyl group in sulfonamide side chain15
O
O
O O
S
S
R1
N
R1
N
F
F
N
N
N
N
N
N
O
O
F
I
II
O
O
S
R1
N
N
N
N
O
Compd
Core R1
Human GPR119 cell line
III
% Remainingb
a
EC50 (nM)
Emax (%)
Hu
Mu
60
I
22
23
24
122
92
100
HO
I
60
16
98
86
73
89
59
82
HO
II
HO
(continued on next page)
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X.-Y. Ye et al. / Bioorg. Med. Chem. Lett. xxx (2014) xxx–xxx
Table 4 (continued)
Compd
Core R1
Human GPR119 cell line
% Remainingb
a
EC50 (nM)
Emax (%)
Hu
Mu
61
II
25
26
101
82
55
HO
III
78
28
78
67
72
67
42
70
HO
HO
III
27
a
EC50 refers to cAMP assay in the human GPR119 cell line.
Represents percentage of compound remaining after incubation in human or mouse microsomes after a 10-min incubation period.
b
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E.; Cuimaraes, C. R. W.; DeNinno, M. P.; Mascitti, V.; Munchhof, M. J.; Robinson,
R. P.; Kohrt, J.; Harris, A. R.; Moore, D. E.; Li, B.; Samp, L.; Lefker, B. A.; Futatsugi,
K.; Kung, D.; Bonin, P. D.; Cornelius, P.; Wang, R.; Salter, E.; Hornby, S.;
Kalgutkar, A. S.; Chen, Y. J. Med. Chem. 2011, 54, 1948.
agonism activity and reasonable metabolic stability in both human
and mouse microsomes. Notably, the hydroxyl group in 24 could
serve as suitable functionality for several different types of pro-
drugs such as phosphate and glycine ester, which could enhance
aqueous solubility and improve pharmacokinetic profiles. Such
modifications is an area for further investigation.
In summary, through medicinal chemistry design and com-
puter-assisted conformational modeling, the initial lead A was
evolved into a series of dihydrobenzofuran derivatives, 3, as potent
GPR119 agonists. Optimization of general structure 3 at various re-
gions of the molecule, including the substituent on dihydrobenzo-
furan, the R1 attachment on the right-hand piperidine nitrogen,
and the left-hand piperidine/piperazine and its attachment R2 led
to the identification of compounds 13c and 24 as potent human
GPR119 modulators with favorable metabolic stability, ion channel
activity, and PXR profiles and as potential candidates for further
in vivo evaluation.
References and notes
1. (a) Wild, S.; Roglic, G.; Green, A.; Sicree, R.; King, H. Diabetes Care 2004, 27,
1047; (b) Shaw, J. E.; Sicree, R. A.; Zimmet, P. Z. Diabetes Res. Clin. Pract. 2010,
87, 4.
2. For the recent reviews of GPR119, see: (a) Ohishi, Takahide; Yoshida, S. Expert
Opin. Investig. Drugs 2012, 21, 321; (b) Jones, R. M.; Leonard, J. N. Annu. Rep.
Med. Chem. 2009, 44, 149; (c) Shah, U. Curr. Opin. Drug Disc. Dev. 2009, 12, 519;
(d) Fyfe, M. C. T.; McCormack, J. G.; Overton, H. A.; Procter, M. J.; Reynet, C.
Expert Opin. Drug Disc. 2008, 3, 403.
3. Lan, L.; Lin, H. V.; Wang, C. F.; Wright, M. J.; Xu, S.; Kang, L.; Juhl, K.; Hedrick, J.
A.; Kowalski, T. J. Br. J. Pharmacol. 2012, 165, 2799.
4. Semple, G.; Fioravanti, B.; Pereira, G.; Calderon, I.; Uy, J.; Choi, K.; Xiong, Y.; Ren,
A.; Morgan, M.; Dave, V.; Thomsen, W.; Unett, D. J.; Xing, C.; Bossie, S.; Carroll,
C.; Chu, Z.; Leonard, J.; Jones, R. M. J. Med. Chem. 2008, 51, 5172.
10. Unpublished results. Our efforts in this area were terminated upon publication
of the patent application WO2 009/038974A1.
11. Under standard Pd-catalyzed hydrogenation condition, the removal of the
hindered benzylic hydroxyl group is slower than the reduction of the
benzofuran double bond. Once the double bond was reduced to single bond,
the hydroxyl group could not be reduced.
12. All compounds in this table are racemic. The enantiomers can be separated by
Chiral Supercritical Fluid Chromatography (Chiralcel OJ-H SFC, 250 ꢁ 21 mm
5. Overton, H. A.; Fyfe, M. C. T.; Reynet, C. Br. J. Pharmacol. 2008, 153, S76 (Suppl.)
and the references cited therein..
ID, 5 lm, ethanol–methanol 50:50 v/v). For example, two enantiomers 13b
6. (a) Semple, G.; Lehmann, J.; Wong, A.; Ren, A.; Bruce, M.; Shin, Y.-J.; Sage, C. R.;
Morgan, M.; Chen, W.-C.; Sebring, K.; Chu, Z.-L.; Leonard, J. N.; Al-Shamma, H.;
Grottick, A. J.; Du, F.; Liang, Y.; Demarest, K.; Jones, R. M. Bioorg. Med. Chem. Lett.
2012, 22, 1750; (b) Thomas PharmaÒ drug report (http://drugnews.thomson-
pharma.com/ddn/home.do).; (c) McWherter, C. The 32nd Annual National
Medicinal Chemistry Symposium, Minnesota, MN, June 6–9, 2010, oral session
2.; (d) Carpenter, A. J. The 32nd Annual National Medicinal Chemistry
Symposium, Minnesota, MN, June 6–9, 2010, oral session 2.; (e) PSN821
structure has not been disclosed. Its close lead PSN408 was disclosed, see The
32nd Annual National Medicinal Chemistry Symposium, Minnesota, MN, June
6–9, 2010, oral session 2.
(Table 3) were synthesized and showed comparable in vitro activity against
GPR119 receptor. Though their specific optical rotation have been recorded,
their absolute stereochemistries were not determined. For simplicity, all
compounds throughout this letter are reported as racemates.
O
O
O O
S
S
N
N
H
N
N
H
N
N
N
N
O
O
F
F
7. (a) Katz, L. B.; Gambale, J. J.; Rothenberg, P. L.; Vanapalli, S. R.; Vaccaro, N.; Xi,
L.; Polidori, D. C.; Vets, E.; Sarich, T. C.; Stein, P. P. Clin. Pharmacol. Ther. 2011, 90,
685; (b) Katz, L. B.; Gambale, J. J.; Rothenberg, P. L.; Vanapalli, S. R.; Vaccaro, N.;
Xi, L.; Sarich, T. C.; Stein, P. P. Diabetes Obes. Metab. 2012, 14, 709.
8. For the review of GPR119 patents prior to 2009, see: Jones, R. M.; Leonard, J. N.;
Buzard, D. J.; Lehmann, J. Expert Opin. Ther. Pat. 2009, 19, 1339.
9. For the most recent publications of medicinal chemistry work of GPR119, see:
(a) Sato, K.; Sugimoto, H.; Rikimaru, K.; Imoto, H.; Kamaura, M.; Negoro, N.;
Tsujihata, Y.; Miyashita, H.; Odani, T.; Murata, T. Bioorg. Med. Chem. Lett. 2014,
22, 1649. http://dx.doi.org/10.1016/j.bmc.2014.01.028; (b) Gillespie, P.;
Goodnow, R. A., Jr.; Saha, G.; Bose, G.; Moulik, K.; Zwingelstein, C.; Myers, M.;
Conde-Knape, K.; Pietranico-Cole, S.; So, S.-S. Bioorg. Med. Chem. Lett. 2014, 24,
949; (c) Darout, E.; Robinson, R. P.; McClure, K. F.; Corbett, M.; Li, B.; Shavnya,
A.; Andrews, M. P.; Jones, C. S.; Li, Q.; Minich, M. L.; Mascitti, V.; Guimarães, C.
13b-enatiomer 1
53.10 o (CH2Cl2, c = 0.2, T = 23.9 oC)
tentative absolute stereochemistry
13b-enatiomer 2
[ ]
D = +51.22 o (CH2Cl2, c = 0.2, T = 24.6 oC)
α
[
α
]
=
−
D
tentative absolute stereochemistry
13. GPR119 agonists were tested in Flp-In-T-Rex-HEK293 cells overexpressing
human GPR119 construct encoding 3 copies of the FLAG epitope tag. The first
198 amino acids of human GPR119 and the C-terminal 137 amino acids of the
mouse receptor was cloned into a tetracycline inducible vector pcDNA5/FRT/
TO (Invitrogen #V6520-20), which includes a hygromycin-resistance marker.
Changes in cAMP concentrations were assessed using the DiscoverX enzyme
fragment complementation (EFC) assay kit (#90007504). Cells were plated
7.5 ꢁ 105 cells/well in 384-well plates, 24 h in advance, with 1 ng/ml
Tetracycline added to the growth media (DMEM #11965, 10% FBS, 2 mM
Please cite this article in press as: Ye, X.-Y.; et al. Bioorg. Med. Chem. Lett. (2014), http://dx.doi.org/10.1016/j.bmcl.2014.03.096

X.-Y. Ye et al. / Bioorg. Med. Chem. Lett. xxx (2014) xxx–xxx
7
L
-glutamine, 200 lg/ml Hygromycin B, 15 lg/ml blasticidin). At time of assay,
14. In addition to cAMP assay in human GPR119 cell line, we also conducted the
assay in human-mouse chimeric GPR119 cell line. Their EC50 values are in good
agreement.
media was replaced with assay buffer (1ꢁ PBS, 25 mM HEPES, pH 7.4, 12 mM
glucose, 0.01% FAF-BSA, 0.1 mM IBMX). Cells were incubated with compound
for 60 min before addition of lysis and detection reagents according to the
manufacturer’s protocol. Fluorescence readings were captured using an
Envision plate reader (Perkin Elmer) and cAMP concentrations calculated
using
compound is repeated are 0.20. The intrinsic activity was expressed as the
percent effect compared to that of the control, 20 M of propan-2-yl 4-({6-[(2-
15. The syntheses of compounds 22–27 were performed using the reactions of
Schemes 2–4 described in this Letter. The primary hydroxyl group or tertiary
hydroxyl group were generated from their corresponding esters via LAH
reduction or nucleophile addition of methylmagnesium bromide. Methyl 3-
(chlorosulfonyl)propanoate and methyl 4-(chlorofulfonyl)butanoate were
prepared from dimethyl 3,30-disulfanediyldipropanoate and dimethyl 4,40-
disulfanediyldibutanoate in 91% and 90% yield, respectively. For detailed
procedure, see: Ye, X.-Y.; Wacker, D. A.; Robl, J. A.; Wang, Y.; PCT Int. Appl. WO
2011140160.
a standard curve. Typical standard deviations in log EC50 when a
l
fluoro-4-methanesulfonylphenyl)amino]pyrimidin-4-yl}oxy)piperidine-1-
carboxylate, defined as 100% as per the following reference: Ariens, E. J. Arch.
Int. Pharmacodyn. Ther. 1954, 99, 32.
Please cite this article in press as: Ye, X.-Y.; et al. Bioorg. Med. Chem. Lett. (2014), http://dx.doi.org/10.1016/j.bmcl.2014.03.096