Synthesis, anti-mycobacterial and cytotoxic evaluation of substituted isoindoline-1,3-dione-4-aminoquinolines coupled: Via alkyl/amide linkers

Article abstract of DOI:10.1039/c8ra10532d

A series of secondary amine-substituted isoindoline-1,3-dione-4-aminoquinolines were prepared via microwave heating and assayed for their anti-mycobacterial activities. The compound with a butyl chain as a spacer between the two pharmacophores and piperidine as the secondary amine component on the isoindoline ring was the most potent and non-cytotoxic among the synthesized compounds, exhibiting a minimum inhibitory concentration (MIC₉₉) of 6.25 μg mL^-1 against Mycobacterium tuberculosis.

Full text of DOI:10.1039/c8ra10532d

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Synthesis, anti-mycobacterial and cytotoxic
evaluation of substituted isoindoline-1,3-dione-4-
Cite this: RSC Adv., 2019, 9, 8515
aminoquinolines coupled via alkyl/amide linkers†
Anu Rani,a Albertus Viljoen,b Matt D. Johansen,b Laurent Kremerbc
a
*
and Vipan Kumar
A series of secondary amine-substituted isoindoline-1,3-dione-4-aminoquinolines were prepared via
microwave heating and assayed for their anti-mycobacterial activities. The compound with a butyl chain
as a spacer between the two pharmacophores and piperidine as the secondary amine component on
the isoindoline ring was the most potent and non-cytotoxic among the synthesized compounds,
Received 24th December 2018
Accepted 3rd March 2019
DOI: 10.1039/c8ra10532d
exhibiting
tuberculosis.
a minimum inhibitory concentration (MIC99)
of 6.25 mg mLꢀ1 against Mycobacterium
rsc.li/rsc-advances
a diarylquinoline – was recently approved by Food and Drug
Administration (FDA) and European Medicine Agency (EMA) for
treating MDR-TB patients.7–9 However, the drug comes with
a black-box warning, which includes the risk of cardiac (QT
prolongation) and hepatic dysfunction and heightened risk of
mortality.10 Meoquine, an orally administered drug, is another
quinoline derivative known for potent anti-tubercular
activity.11–15 Remarkably, numerous derivatives of meoquine
were reported to have good antibacterial and anti-mycobacterial
activities.16,17
Isoindoline-1,3-dione and its derivatives were shown to
possess interesting biological properties18 against a wide panel
of diseases and conditions, such as angiogenic disease,19
inammation,20 cancer,21,22 Parkinson's,23 leprosy, AIDS and
multiple myeloma (MM); as COX inhibitors; antidepressants
and histone deacetylase inhibitors.24 Synthesis of conjugates of
the isoindoline-1,3-dione subunit with different active moieties
afforded active antimicrobials against Mycobacterium leprae and
M. tuberculosis.25
Introduction
Tuberculosis (TB) is a global pandemic caused by the single
infectious agent Mycobacterium tuberculosis. TB has been
a scourge to mankind for thousands of years and roughly more
than one third of the world's population is latently infected.1 In
2016, there were 10.4 million new cases of TB diagnosed with
approximate mortality of 1.3 million among HIV-negative and
an additional 374 000 deaths among HIV-positive people,
mostly in developing countries.2 According to the Revised
National Tuberculosis Control Program (RNTCP), India
accounts for one fourth of the global TB burden with 1.75
million TB patients, including data from both the public and
private health sectors, while 33 820 drug-resistant TB patients
are noted additionally.3 Increasing cases of multidrug-resistant
(MDR) TB and extensively drug-resistant (XDR) TB all over the
world is hindering current TB treatment,4 which includes the
rst-line drugs isoniazid (INH), rifampicin (RIF), pyrazinamide,
ethambutol, and streptomycin, and the second line drugs,
aminoglycosides, polypeptides, uoroquinolones, thioamides,
cycloserine and terizidone.5,6 The emergence of resistant strains
warrants the urgent search for faster-acting, less harmful, more
efficient drug candidates.
A
recent report from our lab highlighted the anti-
mycobacterial potential of isoindoline-1,3-dione-4-
aminoquinolines, exhibiting comparable activity with ethion-
amide and cephalexin (Fig. 1).26 In continuation of our efforts,27
we present herein the synthesis and anti-mycobacterial
The quinoline core has received recent attention as it is one
of the active key building blocks of many drugs. Bedaquiline –
aDepartment of Chemistry, Guru Nanak Dev University, Amritsar-143005, Punjab,
India. E-mail: vipan_org@yahoo.com
bInstitut de Recherche en Infectiologie (IRIM) de Montpellier, CNRS, UMR 9004
´
Universite de Montpellier, France
cINSERM, IRIM, 34293 Montpellier, France
† Electronic supplementary information (ESI) available: Scanned 1H and 13C NMR
spectra of few representative compounds viz. 4c, 4d, 4f, 4k, 4m, 4o, 4s, 7a, 7c, 7e,
7i, 7n, 7q, 8a, 8c, 8d, 8j, 8n and 8p are provided in the electronic supplementary
information. See DOI: 10.1039/c8ra10532d
Fig. 1 Isoindoline-1,3-dione based active anti-TB compounds.
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activities of secondary amino-substituted isoindoline-1,3-dione-
4-aminoquinolines. The spacer length between two pharmaco-
phores as well as the secondary amine functionality at the C4/C5
position of isoindoline-1,3-dione was meticulously altered for
analysing the structure–activity relationship (SAR).
Results and discussion
Synthetic chemistry
For the synthesis of the desired isoindoline-1,3-dione-4-
aminoquinolines with the secondary amine functionality at
the C-4/C-5 position, microwave heating was attempted, as the
reactions were sluggish when carried out under conventional
heating. The microwave assisted reaction between 3-uoro-
phthalic anhydride 1a, N-(7-chloroquinolin-4-yl)diamine 2a28
and piperidine was chosen as model reaction. Different solvents
viz. DMF, DMSO and NMP were screened, both for the single-
pot as well as for the step-wise synthesis and the results are
provided in Scheme 1. As evident, the single pot synthesis gave
the desired scaffold 4a, albeit in moderate yields, when
compared to the step-wise process. The solvent choice seems to
be crucial and better yields were observed by heating in NMP
because of its polar aprotic nature and ease of removal during
purication procedure. Best results obtained via either heating
in single pot synthesis at 160 ꢁC for 5 min (70% yield) or in step-
wise syꢁnthesis by heating at 140 ꢁC for 2 min for step 1 and then
at 160 C for 2 min for step 2 (89% yield).
Having optimized the reaction conditions, the scope of the
developed strategy was then explored for the synthesis of
a series of C-4/C-5 secondary amine linked isoindoline-1,3-
dione-4-aminoquinolines 4b–4t following the stepwise micro-
wave synthesis (Scheme 2). The structure assignment was done
on the basis of spectral data and analytical evidences. For
example, the compound 4s exhibited a molecular ion peak at m/
z 508.2084 [M + H]+ in the High Resolution Mass Spectrum
(HRMS). The noteworthy features of its 1H NMR spectrum
encompassed the appearance of multiplet at d 1.76–1.86, two
triplets at 3.34 (J ¼ 6.6 Hz) and 3.73 (J ¼ 6.4 Hz) because of
methylenes, two triplets at 2.66 (J ¼ 4.7 Hz) and 3.40 (J ¼ 4.6 Hz)
Scheme 2 Microwave-promoted synthesis of C-4/C-5 secondary
amine substituted isoindoline-1,3-dione-4-aminoquinolines (4b–t).
because of piperazine ring protons and a doublet at d 7.00 (J ¼
8.4 Hz) because of aromatic ring protons. The presence of
absorption peaks at d 169.1 and 168.7, corresponding to
carbonyl carbons in the 13C NMR spectrum along with methy-
lenes at d 25.5, 26.5, 37.2 and 42.8 and piperazine carbons at
d 47.6 and 52.4, as corroborated by the 13C NMR (DEPT) spec-
trum, validated the assigned structure. For the synthesis of
conjugates 7a–r, amide coupling of 6 with N-(7-chloroquinolin-
4-yl)diamine 2 was done using amide coupling reagents EDC–
HOBt at room temperature. Further, C-5 ouro substituted
conjugates 7m–r were reacted with different secondary amines
under microwave heating resulted in the formation of desired
conjugates 8a–r in good to excellent yields (Scheme 3). Spectral
data and analytical evidences were used to assign the structure
to the synthesized conjugates.
In vitro anti-mycobacterial evaluation
The synthesized scaffolds were assayed for their anti-
mycobacterial activities against M. tuberculosis mc26230 and
the result are enlisted in Table 1. As evident, all the synthesized
compounds were not as active as isoniazid, but some of them
showed promising activities. A closer analysis of Table 1 showed
the dependence of activity on the nature of linker between two
pharmacophores, the nature of substituent at C-4/C-5 position
of isoindoline-1,3-dione as well as the linker used as spacer.
Cytotoxic studies of all the synthesized compounds were also
carried out against Vero cells so as to conrm whether the
observed activities were due to their inherent anti-
mycobacterial efficacy or cytotoxicity (Table 1, Fig. 2).
Scheme
1 Optimizing microwave-assisted synthesis of the C-4-
piperidine ring substituted isoindoline-1,3-dione-4-aminoquinolines Scheme 3 Synthesis of C-5 substituted isoindoline-1,3-dione linked
4a.
with 4-aminoquinolines via amide spacer 7a–r, 8a–r.
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Table 1 In vitro anti-mycobacterial activity of synthesized compounds against M. tuberculosis mc26230 and cytotoxicity against Vero cells
Code
R
m
n
MIC99a (mg mLꢀ1
)
IC50 (mg mLꢀ1) (cytotoxicity)
SI
4a
4b
4c
4d
4e
4f
4g
4h
4i
4j
4k
4l
4m
4n
4o
4p
4q
4r
4-Piperidyl
4-Piperidyl
4-Piperidyl
4-Piperidyl
5-Piperidyl
5-Piperidyl
5-Piperidyl
5-Piperidyl
4-Morpholinyl
4-Morpholinyl
4-Morpholinyl
4-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
H
H
H
H
H
H
H
H
H
H
H
H
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
1
1
1
1
2
2
2
2
3
3
3
3
1
1
1
2
2
2
1
1
1
2
2
2
1
1
1
2
2
2
1
1
1
2
3
4
6
2
3
4
6
2
3
4
6
2
3
4
6
2
3
4
6
2
4
6
8
2
4
6
8
2
4
6
8
2
4
6
2
4
6
2
4
6
2
4
6
2
4
6
2
4
6
2
4
6
2
4
6
100
12.5
6.25
6.25
12.5
12.5
6.25
12.5
100
50
25.55
96.87
26.59
56.87
13.95
>100.4
>100
99.3
28.43
>100
36.05
22.26
12.15
14.73
11.30
3.537
4.91
9.017
15.00
29.84
>100
>100
>100
>100
>100
>100
41.88
>100
>100
>100
>100
52.93
>100
>100
>100
41.0
51.44
28.42
>100
>100
11.07
13.42
72.52
>100
21.28
23.78
>100
100
0.26
7.75
4.25
9.10
1.12
>8
>16
7.94
0.28
>2
2.88
3.56
0.24
0.29
0.904
0.57
0.05
0.72
1.2
2.38
>0.5
>4
>4
>8
>8
>2
1.67
>4
>8
12.5
6.25
50
50
12.5
6.25
100
12.5
12.5
12.5
200
25
4s
4t
7a
7b
7c
7d
7e
7f
7g
7h
7i
25
12.5
12.5
50
25
25
12.5
25
50
7j
7k
7l
>4
>2
12.5
6.25
25
200
200
200
200
50
12.5
200
100
200
200
50
12.5
100
50
200
100
50
100
200
ND
100
25
4.23
>16
>4
>0.5
0.20
0.25
0.14
>2
7m
7n
7o
7p
7q
7r
8a
8b
8c
8d
8e
8f
8g
8h
8i
8j
8k
8l
5-F
5-F
5-F
5-F
5-F
5-F
5-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-Morpholinyl
5-(Diethylamino)
5-(Diethylamino)
5-(Diethylamino)
5-(Diethylamino)
5-(Diethylamino)
5-(Diethylamino)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
5-(2-(Piperazin-1-yl)ethan-1-ol)
Isoniazid
>8
0.05
0.13
0.36
>0.5
0.42
1.90
>1
9.5
0.22
>1
>2
>1
>0.5
—
0.97
>4
44
>100
>100
>100
>100
ND
97.65
>100
>100
8m
8n
8o
8p
8q
8r
2
2
2
INH
0.019
a
The MIC expressed in mg mLꢀ1 were determined using the microdilution method in broth medium; m, n are alkyl chain length (Schemes 1–3).
Among isoindoline-1,3-dione-4-aminoquinolines linked via dione ring, not only improved the anti-TB activity but also
alkyl chain 4a–t, the replacement of uoro-substituent reduced their cytotoxicity, which were in the range of 5.03–20.92
(compound I, Fig. 1) with secondary amine on isoindoline-1,3- mg mLꢀ1
.
Introduction of a piperidine ring at the C-4/C-5
26
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position among compounds, 4a–4h revealed an increase in induction of morpholine ring. The compounds 4k, 4l, 4o and 4p
activity with the increase in alkyl chain length as evident by 4c (n exhibited MIC of 12.5, 6.25, 12.5, 6.25 mg mLꢀ1 respectively.
¼ 4), 4d (n ¼ 6) and 4g (n ¼ 4), exhibiting MIC values of 6.25. Introduction of hydroxy-ethyl-piperazine as the secondary
Similar improvement in anti-TB activities was observed with the amine counterpart considerably enhanced the anti-
Fig. 2 Cytotoxicity of synthesized compounds (4a–t, 7a–r, 8a–r) on Vero cells. Shown are means and standard deviations calculated from two
independent experiments. DMSO is included as a negative control, while SDS was included as a positive control.
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instrument using sealed 2–5 mL process vials. Reaction times
refer to irradiation time at the target temperature, not the total
irradiation time. The temperature was measured with an IR
sensor. Chemical shi values are specied as parts per million
(ppm) downeld from TMS, while coupling constant (J) values
are in hertz. Patterns of splitting are designated as s: singlet, d:
doublet, t: triplet, m: multiplet, dd: double doublet, ddd:
doublet of a doublet of a doublet, and br: broad peak. 13C NMR
spectra were recorded on Bruker 125 MHz and Jeol 100 MHz
spectrometers in CDCl3 and DMSO-d6. High Resolution Mass
Spectra (HRMS) were recorded on a Bruker-micrOTOF-Q II
spectrometer using ESI as the ion source.
Fig.
3 Generalized SAR of synthesized isoindoline-1,3-dione-4-
aminoquinolines
mycobacterial activity even at shorter chain lengths. 4r, 4s and
4t having propyl, butyl and hexyl spacer length along with
hydroxyl-ethyl-piperazine at C-5 position exhibited MIC values
of 12.5 mg mLꢀ1, for all three compounds, but also increased
their respective cytotoxicity.
General procedure for the preparation of C-4/C-5 secondary
amine substituted isoindoline-1,3-dione-4-aminoquinolines
(4a–t)
Among the amide tethered isoindoline-1,3-dione-4-
aminoquinoline 7a–r, although
a
decrease in anti-
To a microwave reaction vial was added a solution of C-3/C-4
uoro-phthalic anhydride (1.0 mmol) in 0.5 mL of NMP (N-
methylpyrrolidin-2-one) and 4-aminoquinoline-diamines (1.0
mmol). Aer sealing with a PTFE cap, the vessel was heated to
130 ꢁC for 2 min in the microwave reactor. Aer accomplish-
ment of the rst step, as obvious from TLC, secondary amine
(1.2 mmol) was added in the same reaction vial. The reaction
mixture was again heated at 160 ꢁC for 5 min in the microwave
reactor and the completion was ascertained using TLC. Aer
completion, the contents were poured in water (20 mL) result-
ing in the precipitation of the desired product. The obtained
product was ltered and re-crystallized using absolute ethanol.
2-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-4-(piperidin-1-yl)
isoindoline-1,3-dione (4a). Yield 89%; dark yellow solid; mp 140–
141 C; H NMR (500 MHz, CDCl3) d 1.63–1.68 (m, 2H, –CH2–);
1.79–1.85 (m, 4H, 2ꢂ –CH2–); 3.36 (t, J ¼ 5.2 Hz, 4H, 2ꢂ –CH2–);
3.35–3.47 (m, 2H, –CH2–); 3.78 (t, J ¼ 6.4 Hz, 2H, –CH2–); 5.39 (s,
1H, NH-exchangeable with D2O); 6.41 (d, J ¼ 5.2 Hz, 1H, Ar–H);
7.14 (d, J ¼ 8.2 Hz, 1H, Ar–H); 7.32–7.37 (m, 2H, Ar–H); 7.54–7.58
(m, 1H, Ar–H); 7.82 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.98 (s, 1H, Ar–H);
8.51 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C NMR (125 MHz, CDCl3) d 24.1,
25.7, 37.3, 43.2, 52.9, 99.1, 114.8, 117.3, 117.5, 121.3, 123.4, 125.3,
128.7, 134.6, 134.9, 135.2, 149.3, 149.9, 150.9, 152.1, 168.2, 168.8.
HRMS calcd for C24H23ClN4O2 [M + H]+ 435.1543 found 435.1547.
2-(3-((7-Chloroquinolin-4-yl)amino)propyl)-4-(piperidin-1-yl)
isoindoline-1,3-dione (4b). Yield 88%; dark yellow solid; mp
121–122 ꢁC; 1H NMR (500 MHz, CDCl3) d 1.62–1.67 (m, 2H,
–CH2–); 1.82–1.88 (m, 4H, 2ꢂ –CH2–); 1.98 (m, 2H, –CH2–), 3.32
(t, J ¼ 5.1 Hz, 4H, 2ꢂ –CH2–); 3.35–3.40 (m, 2H, –CH2–); 3.80 (t, J
¼ 6.4 Hz, 2H, –CH2–); 5.36 (s, 1H, NH-exchangeable with D2O);
6.40 (d, J ¼ 5.1 Hz, 1H, Ar–H); 7.18 (d, J ¼ 8.2 Hz, 1H, Ar–H);
7.32–7.36 (m, 2H, Ar–H); 7.51–7.55 (m, 1H, Ar–H); 7.81 (d, J ¼
8.8 Hz, 1H, Ar–H); 7.94 (s, 1H, Ar–H); 8.51 (d, J ¼ 5.2 Hz, 1H, Ar–
H); 13C NMR (125 MHz, CDCl3) d 24.0, 25.5, 26.6, 37.2, 43.4,
mycobacterial activity has been observed in general, the
compounds were non-cytotoxic in nature. Among the scaffold
having n ¼ 1 (Glycine), the compound 7d (R ¼ H, n ¼ 8) and 7m
(R ¼ F, n ¼ 2) displayed better activity proles compared to the
other members of the series with MIC of 12.5 and 6.25 mg mLꢀ1
respectively. The introduction of b-alanine and g-aminobutyric
acid showed more or less similar activity proles with low
cytotoxicity. The introduction of secondary amine functionality
among the amide-linked series resulted in considerable loss of
anti-mycobacterial activities except for the compound 8b which
was non-cytotoxic and exhibited a MIC of 12.5 mg mLꢀ1. The
generalized SAR of the synthesized isoindoline-1,3-dione-4-
aminoquinolines (both the alkyl chain as well as amide-core
tethered) for their anti-mycobacterial activity against mc26230
strain of M. tuberculosis and cytotoxicity against Vero cells is
depicted in Fig. 3.
1
ꢁ
Conclusion
In conclusion, the present describes the microwave-promoted
synthesis of a series of C-4/C-5 secondary amine substituted
isoindoline-1,3-dione-4-aminoquinolines coupled via alkyl/
amide core as linker. The synthesized scaffolds were evaluated
for their anti-mycobacterial proles against the M. tuberculosis
mc26230 strain while cytotoxicity was determined against Vero
cells. The compound 4g with an optimum combination of
piperidine as the secondary amine at C-5 position and a butyl
chain as spacer proved to be non-cytotoxic with a MIC99 of 6.25
mg mLꢀ1
.
Experimental section
General
Veego Precision Digital Melting Point apparatus (MP-D) was 52.7, 99.0, 114.6, 117.1, 117.4, 121.2, 123.4, 125.2, 128.8, 134.3,
used for the determination of melting points which are uncor- 134.8, 135.1, 149.4, 149.9, 150.8, 152.0, 168.1, 168.9. HRMS
rected. 1H NMR spectra were recorded in deuterated chloroform calcd for C25H25ClN4O2 [M + H]+ 449.1700 found 449.1708.
(CDCl3)/DMSO-d6 using Bruker 500 (500 MHz) and Jeol 400 (400
2-(4-((7-Chloroquinolin-4-yl)amino)butyl)-4-(piperidin-1-yl)
MHz) spectrometers while TMS is used as internal standard. isoindoline-1,3-dione (4c). Yield 89%; dark brown solid; mp 110–
1
ꢁ
Microwave reactions were performed in a Biotage® Initiator+ 111 C; H NMR (500 MHz, CDCl3) d 1.64–1.67 (m, 2H, –CH2–);
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1.80–1.89 (m, 8H, 4ꢂ –CH2–); 3.30 (t, J ¼ 5.3 Hz, 4H, 2ꢂ –CH2–); 134.7, 149.1, 149.5, 151.7, 155.3, 169.0, 169.5. HRMS calcd for
3.37–3.41 (m, 2H, –CH2–); 3.77 (t, J ¼ 6.5 Hz, 2H, –CH2–); 5.37 (s, C26H27ClN4O2 [M + H]+ 463.1856 found 463.1874.
1H, NH-exchangeable with D2O); 6.41 (d, J ¼ 5.4 Hz, 1H, Ar–H);
2-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-5-(piperidin-1-yl)
7.16 (d, J ¼ 8.5 Hz, 1H, Ar–H); 7.33–7.37 (m, 2H, Ar–H); 7.53–7.56 isoindoline-1,3-dione (4h). Yield 89%; yellow solid; mp 88–89 ꢁC;
(m, 1H, Ar–H); 7.80 (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.95 (s, 1H, Ar–H); 1H NMR (500 MHz, CDCl3) d 1.31–1.35 (m, 4H, 2ꢂ –CH2–), 1.52–
8.52 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, CDCl3) d 24.0, 1.56 (m, 2H, –CH2–), 1.63–1.78 (m, 8H, 4ꢂ –CH2–); 3.34–3.41 (m,
25.6, 25.9, 26.5, 37.2, 43.0, 52.7, 99.0, 114.7, 117.2, 117.4, 121.2, 6H, 3ꢂ –CH2–); 3.75 (t, J ¼ 6.2 Hz, 2H, –CH2–); 6.10 (s, 1H, NH-
123.2, 125.2, 128.7, 134.4, 134.7, 135.0, 149.1, 149.7, 150.9, 152.0, exchangeable with D2O); 6.40 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.01 (d,
168.1, 168.7. HRMS calcd for C26H27ClN4O2 [M + H]+ 463.1856 J ¼ 8.0 Hz, 1H, Ar–H); 7.24 (s, 1H, Ar–H); 7.40 (d, J ¼ 9.0 Hz, 1H,
found 463.1863.
Ar–H); 7.64 (d, J ¼ 8.5 Hz, 1H, Ar–H); 7.88–7.94 (m, 2H, Ar–H);
2-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-4-(piperidin-1-yl)
8.51 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C NMR (125 MHz, CDCl3) d 24.2,
isoindoline-1,3-dione (4d). Yield 90%; dark brown solid; mp 85– 25.1, 26.7, 26.7, 28.3, 28.7, 34.3, 39.2, 48.4, 98.2, 108.0, 117.0,
86 ꢁC; 1H NMR (500 MHz, CDCl3) d 1.40–1.56 (m, 4H, 2ꢂ –CH2–); 117.2, 118.0, 121.2, 125.0, 125.2, 128.6, 134.5, 134.7, 149.1, 149.3,
1.63–1.67 (m, 2H, –CH2–); 1.70–1.78 (m, 4H, 2ꢂ –CH2–); 1.80–1.83 151.6, 155.3, 169.1, 169.2. HRMS calcd for C28H31ClN4O2 [M + H]+
(m, 4H, 2ꢂ –CH2–); 3.28–3.33 (m, 6H, 3ꢂ –CH2–); 3.68 (t, J ¼ 491.2169 found 491.2178.
5.5 Hz, 2H, –CH2–); 5.21 (s, 1H, NH-exchangeable with D2O); 6.41
2-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-4-morpholinoiso-
(d, J ¼ 5.4 Hz, 1H, Ar–H); 7.16 (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.33–7.37 indoline-1,3-dione (4i). Yield 92%; yellow solid; mp 163–164 ꢁC;
(m, 2H, Ar–H); 7.52–7.55 (m, 1H, Ar–H); 7.76 (d, J ¼ 8.9 Hz, 1H, 1H NMR (400 MHz, CDCl3) d 3.36–3.40 (m, 6H, 3ꢂ –CH2–); 3.74
Ar–H); 7.96 (s, 1H, Ar–H); 8.53 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (t, J ¼ 6.4 Hz, 2H, –CH2–); 3.95 (t, J ¼ 4.5 Hz, 4H, 2ꢂ –CH2–); 5.30
(125 MHz, CDCl3) d 24.0, 25.9, 26.2, 26.3, 28.3, 28.5, 37.3, 42.8, (s, 1H, NH-exchangeable with D2O); 6.36 (d, J ¼ 5.2 Hz, 1H, Ar–
52.7, 99.0, 114.7, 117.2, 117.7, 121.0, 123.1, 125.2, 128.7, 134.5, H); 7.11 (d, J ¼ 8.3 Hz, 1H, Ar–H); 7.31–7.38 (m, 2H, Ar–H); 7.57–
134.7, 134.9, 149.1, 149.7, 150.9, 152.0, 168.1, 168.7. HRMS calcd 7.61 (m, 1H, Ar–H); 7.75 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.88 (d, J ¼
for C28H31ClN4O2 [M + H]+ 491.2169 found 491.2162.
2.0 Hz, 1H, Ar–H); 8.46 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C NMR (100
MHz) d 37.5, 43.3, 51.7, 66.9, 99.0, 115.8, 117.1, 118.2, 121.4,
2-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-5-(piperidin-1-yl)
isoindoline-1,3-dione (4e). Yield 85%; yellow solid; mp 180– 122.8, 125.4, 128.9, 134.4, 134.8, 135.6, 149.2, 149.8, 150.2,
181 ꢁC; 1H NMR (500 MHz, CDCl3) d 1.64–1.76 (m, 6H, 3ꢂ –CH2– 152.1, 168.3, 168.6. HRMS calcd for C23H21ClN4O3 [M + H]+
); 3.37–3.44 (m, 6H, 3ꢂ –CH2–); 3.79 (t, J ¼ 6.1 Hz, 2H, –CH2–); 437.1336 found 437.1344.
6.11 (s, 1H, NH-exchangeable with D2O); 6.42 (d, J ¼ 5.3 Hz, 1H,
2-(3-((7-Chloroquinolin-4-yl)amino)propyl)-4-morpholinoiso-
ꢁ
Ar–H); 7.03 (d, J ¼ 8.0 Hz, 1H, Ar–H); 7.27 (s, 1H, Ar–H); 7.41 (d, J indoline-1,3-dione (4j). Yield 90%; yellow solid; mp 141–142 C;
¼ 9.0 Hz, 1H, Ar–H); 7.67 (d, J ¼ 8.6 Hz, 1H, Ar–H); 7.92–7.97 (m, 1H NMR (400 MHz, CDCl3) d 2.00–2.05 (m, 2H, –CH2–); 3.34–3.39
2H, Ar–H); 8.51 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C NMR (125 MHz, (m, 6H, 3ꢂ –CH2–); 3.71 (t, J ¼ 6.5 Hz, 2H, –CH2–); 3.94 (t, J ¼
CDCl3) d 24.3, 25.3, 34.9, 39.7, 48.9, 98.8, 108.3, 117.2, 117.4, 4.3 Hz, 4H, 2ꢂ –CH2–); 5.28 (s, 1H, NH-exchangeable with D2O);
118.4, 121.3, 125.1, 125.3, 128.7, 134.6, 134.8, 149.3, 149.6, 6.35 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.12 (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.30–
151.8, 155.4, 169.2, 169.7. HRMS calcd for C24H23ClN4O2 [M + 7.37 (m, 2H, Ar–H); 7.56–7.59 (m, 1H, Ar–H); 7.75 (d, J ¼ 8.9 Hz,
H]+ 435.1543 found 435.1549.
1H, Ar–H); 7.89 (d, J ¼ 2.0 Hz, 1H, Ar–H); 8.45 (d, J ¼ 5.3 Hz, 1H,
2-(3-((7-Chloroquinolin-4-yl)amino)propyl)-5-(piperidin-1-yl)
Ar–H); 13C NMR (100 MHz) d 28.4, 37.3, 43.1, 51.6, 66.8, 99.0,
isoindoline-1,3-dione (4f). Yield 88%; yellow solid; mp 97–98 ꢁC; 115.9, 117.1, 118.1, 121.3, 122.8, 125.4, 128.8, 134.5, 134.9, 135.6,
1H NMR (500 MHz, CDCl3) d 1.65–1.78 (m, 6H, 3ꢂ –CH2–); 2.00– 149.1, 149.8, 150.1, 152.1, 168.2, 168.7. HRMS calcd for
2.05 (m, 2H, –CH2–); 3.39–3.45 (m, 6H, 3ꢂ –CH2–); 3.80 (t, J ¼ C24H23ClN4O3 [M + H]+ 451.1492 found 451.1477.
6.0 Hz, 2H, –CH2–); 6.12 (s, 1H, NH-exchangeable with D2O);
2-(4-((7-Chloroquinolin-4-yl)amino)butyl)-4-morpholinoiso-
6.42 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.01 (d, J ¼ 8.0 Hz, 1H, Ar–H); 7.26 indoline-1,3-dione (4k). Yield 89%; yellow solid; mp 110–111 ꢁC;
(s, 1H, Ar–H); 7.40 (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.65 (d, J ¼ 8.5 Hz, 1H NMR (400 MHz, CDCl3) d 1.74–1.87 (m, 4H, 2ꢂ –CH2–); 3.30–
1H, Ar–H); 7.90–7.95 (m, 2H, Ar–H); 8.51 (d, J ¼ 5.3 Hz, 1H, Ar– 3.37 (m, 6H, 3ꢂ –CH2–); 3.73 (t, J ¼ 6.6 Hz, 2H, –CH2–); 3.91 (t, J
H); 13C NMR (125 MHz, CDCl3) d 24.2, 25.2, 26.7, 34.6, 39.2, ¼ 4.5 Hz, 4H, 2ꢂ –CH2–); 5.29 (s, 1H, NH-exchangeable with
48.8, 98.6, 108.2, 117.2, 117.4, 118.3, 121.4, 125.0, 125.3, 128.6, D2O); 6.37 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.12 (d, J ¼ 8.4 Hz, 1H, Ar–
134.5, 134.8, 149.2, 149.5, 151.9, 155.4, 169.1, 169.6. HRMS H); 7.31–7.39 (m, 2H, Ar–H); 7.54–7.58 (m, 1H, Ar–H); 7.73 (d, J
calcd for C25H25ClN4O2 [M + H]+ 449.1700 found 449.1712.
¼ 9.0 Hz, 1H, Ar–H); 7.91 (d, J ¼ 2.1 Hz, 1H, Ar–H); 8.47 (d, J ¼
2-(4-((7-Chloroquinolin-4-yl)amino)butyl)-5-(piperidin-1-yl)
5.4 Hz, 1H, Ar–H); 13C NMR (100 MHz) d 25.7, 26.5, 37.4, 43.0,
isoindoline-1,3-dione (4g). Yield 87%; yellow solid; mp 91–92 ꢁC; 51.5, 66.9, 99.1, 115.9, 117.2, 118.1, 121.2, 122.8, 125.3, 128.7,
1H NMR (500 MHz, CDCl3) d 1.41–1.49 (m, 4H, 2ꢂ –CH2–), 1.64– 134.5, 134.9, 135.5, 149.0, 149.8, 150.1, 152.0, 168.1, 168.6.
1.77 (m, 6H, 3ꢂ –CH2–); 3.37–3.44 (m, 6H, 3ꢂ –CH2–); 3.78 (t, J ¼ HRMS calcd for C25H25ClN4O3 [M + H]+ 465.1649 found
6.1 Hz, 2H, –CH2–); 6.11 (s, 1H, NH-exchangeable with D2O); 6.41 465.1665.
(d, J ¼ 5.3 Hz, 1H, Ar–H); 7.00 (d, J ¼ 8.1 Hz, 1H, Ar–H); 7.26 (s,
2-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-4-morpholinoiso-
1H, Ar–H); 7.41 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.64 (d, J ¼ 8.6 Hz, 1H, indoline-1,3-dione (4l). Yield 88%; yellow solid; mp 89–90 ꢁC; 1H
Ar–H); 7.89–7.94 (m, 2H, Ar–H); 8.52 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13
C
NMR (400 MHz, CDCl3) d 1.35–1.39 (m, 4H, 2ꢂ –CH2–); 1.50–
NMR (125 MHz, CDCl3) d 24.1, 25.2, 26.7, 26.9, 34.5, 39.2, 48.7, 1.54 (m, 2H, –CH2–); 1.64–1.77 (m, 4H, 2ꢂ –CH2–); 3.29–3.36 (m,
98.4, 108.1, 117.2, 117.3, 118.2, 121.4, 125.1, 125.2, 128.7, 134.4, 6H, 3ꢂ –CH2–); 3.72 (t, J ¼ 6.5 Hz, 2H, –CH2–); 3.90 (t, J ¼ 4.6 Hz,
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4H, 2ꢂ –CH2–); 5.28 (s, 1H, NH-exchangeable with D2O); 6.36 (d, 42.9, 47.6, 66.1, 99.0, 108.2, 117.2, 117.5, 120.8, 121.1, 124.7,
J ¼ 5.3 Hz, 1H, Ar–H); 7.11 (d, J ¼ 8.5 Hz, 1H, Ar–H); 7.30–7.38 125.2, 128.6, 134.4, 134.7, 149.0, 149.6, 152.1, 155.3, 168.5,
(m, 2H, Ar–H); 7.53–7.56 (m, 1H, Ar–H); 7.71 (d, J ¼ 8.9 Hz, 1H, 169.1. HRMS calcd for C27H29ClN4O3 [M + H]+ 493.1962 found
Ar–H); 7.90 (d, J ¼ 2.0 Hz, 1H, Ar–H); 8.45 (d, J ¼ 5.4 Hz, 1H, Ar– 493.1976.
H); 13C NMR (100 MHz) d 25.3, 26.6, 28.4, 28.8, 37.2, 43.2, 51.2,
2-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-5-(4-(2-hydroxyethyl)
66.7, 99.0, 115.8, 117.0, 118.0, 121.1, 122.6, 125.2, 128.7, 134.3, piperazin-1-yl)isoindoline-1,3-dione (4q). Yield 88%; dark brown
1
ꢁ
134.7, 135.3, 149.1, 149.6, 150.2, 152.1, 168.0, 168.4. HRMS solid; mp 211–212 C; H NMR (400 MHz, CDCl3) d 2.65 (t, J ¼
calcd for C27H29ClN4O3 [M + H]+ 493.1962 found 493.1971.
5.4 Hz, 2H, –CH2); 2.69 (t, J ¼ 5.0 Hz, 4H, 2ꢂ –CH2–); 3.39 (t, J ¼
6.4 Hz, 2H, –CH2–); 3.45 (t, J ¼ 5.0 Hz, 4H, 2ꢂ –CH2–); 3.70 (t, J ¼
2-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-5-morpholinoiso-
indoline-1,3-dione (4m). Yield 89%; dark brown solid; mp 192– 5.3 Hz, 2H, –CH2–); 3.77 (t, J ¼ 6.5 Hz, 2H, –CH2–); 6.41 (d, J ¼
193 ꢁC; 1H NMR (500 MHz, CDCl3) d 3.38 (t, J ¼ 4.8 Hz, 4H, 2ꢂ 5.5 Hz, 1H, Ar–H); 7.04 (d, J ¼ 8.3 Hz, 1H, Ar–H); 7.23 (s, 1H, Ar–H);
–CH2–); 3.52–3.55 (m, 2H, –CH2–); 3.88 (t, J ¼ 4.8 Hz, 4H, 2ꢂ 7.35 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.65 (d, J ¼ 8.2 Hz, 1H, Ar–H); 7.75
–CH2–); 4.15 (t, J ¼ 5.2 Hz, 2H, –CH2–); 6.13 (s, 1H, NH- (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.93 (s, 1H, Ar–H); 8.49 (d, J ¼ 5.4 Hz, 1H,
exchangeable with D2O); 6.36 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.05 Ar–H); 13C NMR (100 MHz, CDCl3) d 37.4, 42.9, 47.8, 52.5, 57.9,
(d, J ¼ 8.4 Hz, 1H, Ar–H); 7.30 (s, 1H, Ar–H); 7.43 (d, J ¼ 8.9 Hz, 59.5, 99.1, 108.5, 117.0, 117.5, 120.1, 121.0, 124.9, 125.3, 128.9,
1H, Ar–H); 7.73 (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.80 (d, J ¼ 8.9 Hz, 1H, 134.6, 134.8, 149.1, 149.8, 152.0, 155.3, 168.7, 169.1. HRMS calcd
Ar–H); 7.94 (s, 1H, Ar–H); 8.52 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C for C25H26ClN5O3 [M + H]+ 480.1758 found 480.1771.
NMR (125 MHz, CDCl3) d 36.7, 43.8, 47.5, 66.3, 98.6, 108.5,
2-(3-((7-Chloroquinolin-4-yl)amino)propyl)-5-(4-(2-hydroxyethyl)
117.1, 117.7, 120.1, 121.5, 125.2, 125.6, 128.5, 134.2, 134.9, piperazin-1-yl)isoindoline-1,3-dione (4r). Yield 89%; dark brown
148.9, 149.7, 151.9, 155.6, 169.1, 169.5. HRMS calcd for solid; mp 197–198 ꢁC; 1H NMR (400 MHz, CDCl3) d 1.99–2.05 (m,
C
23H21ClN4O3 [M + H]+ 437.1336 found 437.1349.
2-(3-((7-Chloroquinolin-4-yl)amino)propyl)-5-morpholinoiso-
2H, 2ꢂ –CH2–), 2.63 (t, J ¼ 5.3 Hz, 2H, –CH2); 2.68 (t, J ¼ 5.0 Hz,
4H, 2ꢂ –CH2–); 3.36 (t, J ¼ 6.6 Hz, 2H, –CH2–); 3.43 (t, J ¼ 5.1 Hz,
indoline-1,3-dione (4n). Yield 85%; dark brown solid; mp 185– 4H, 2ꢂ –CH2–); 3.68 (t, J ¼ 5.4 Hz, 2H, –CH2–); 3.76 (t, J ¼ 6.4 Hz,
1
ꢁ
186 C; H NMR (500 MHz, CDCl3) d 1.65–1.70 (m, 2H, –CH2–); 2H, –CH2–); 6.39 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.03 (d, J ¼ 8.3 Hz, 1H,
3.36–3.45 (m, 6H, 3ꢂ –CH2–); 3.80 (t, J ¼ 6.4 Hz, 2H, –CH2–); 3.90 Ar–H); 7.22 (s, 1H, Ar–H); 7.33 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.63 (d, J ¼
(t, J ¼ 4.7 Hz, 4H, 2ꢂ –CH2–); 5.30 (s, 1H, NH-exchangeable with 8.3 Hz, 1H, Ar–H); 7.74 (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.93 (s, 1H, Ar–H);
D2O); 6.40 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.04 (d, J ¼ 8.4 Hz, 1H, Ar–H); 8.48 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (100 MHz, CDCl3) d 26.8,
7.28 (s, 1H, Ar–H); 7.40 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.70 (d, J ¼ 37.8, 42.7, 47.7, 52.6, 57.6, 59.3, 99.1, 108.3, 117.2, 117.8, 120.2,
8.3 Hz, 1H, Ar–H); 7.78 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.94 (s, 1H, Ar– 121.3, 124.9, 125.5, 128.6, 134.6, 134.9, 149.2, 149.8, 151.7, 155.4,
H); 8.52 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, CDCl3) 168.6, 169.2. HRMS calcd for C26H28ClN5O3 [M + H]+ 494.1914,
d 26.8, 37.5, 43.0, 47.8, 66.2, 99.0, 108.4, 117.0, 117.6, 120.5, 121.4, found 494.2160.
124.9, 125.4, 128.6, 134.3, 134.8, 149.0, 149.6, 152.0, 155.5, 168.9,
2-(4-((7-Chloroquinolin-4-yl)amino)butyl)-5-(4-(2-hydroxyethyl)
169.3. HRMS calcd for C24H23ClN4O3 [M + H]+ 451.1492 found piperazin-1-yl)isoindoline-1,3-dione (4s). Yield 87%; dark brown
451.1486.
2-(4-((7-Chloroquinolin-4-yl)amino)butyl)-5-morpholinoiso-
solid; mp 155–156 ꢁC; 1H NMR (400 MHz, CDCl3) d 1.76–1.86 (m,
4H, 2ꢂ –CH2–); 2.61 (t, J ¼ 5.1 Hz, 2H, –CH2); 2.66 (t, J ¼ 4.7 Hz,
indoline-1,3-dione (4o). Yield 85%; dark brown solid; mp 180– 4H, 2ꢂ –CH2–); 3.34 (t, J ¼ 6.6 Hz, 2H, –CH2–); 3.40 (t, J ¼ 4.6 Hz,
181 ꢁC; 1H NMR (500 MHz, CDCl3) d 1.85–1.90 (m, 4H, 2ꢂ –CH2– 4H, 2ꢂ –CH2–); 3.66 (t, J ¼ 5.1 Hz, 2H, –CH2–); 3.73 (t, J ¼ 6.4 Hz,
); 3.36–3.41 (m, 6H, 3ꢂ –CH2–); 3.77 (t, J ¼ 6.5 Hz, 2H, –CH2–); 2H, –CH2–); 6.37 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.00 (d, J ¼ 8.4 Hz, 1H,
3.89 (t, J ¼ 4.8 Hz, 4H, 2ꢂ –CH2–); 5.29 (s, 1H, NH-exchangeable Ar–H); 7.22 (s, 1H, Ar–H); 7.34 (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.63 (d, J ¼
with D2O); 6.41 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.04 (d, J ¼ 8.4 Hz, 1H, 8.3 Hz, 1H, Ar–H); 7.73 (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.91 (s, 1H, Ar–H);
Ar–H); 7.26 (s, 1H, Ar–H); 7.37 (d, J ¼ 8.9 Hz, 1H, Ar–H); 7.68 (d, J 8.47 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (100 MHz, CDCl3) d 25.5,
¼ 8.4 Hz, 1H, Ar–H); 7.76 (d, J ¼ 9.0 Hz, 1H, Ar–H); 7.95 (s, 1H, 26.5, 37.2, 42.8, 47.6, 52.4, 57.7, 59.3, 99.0, 108.4, 117.1, 117.6,
Ar–H); 8.52 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (125 MHz, CDCl3) 120.1, 121.1, 124.8, 125.3, 128.6, 134.4, 134.8, 149.0, 149.6, 151.9,
d 25.6, 26.5, 37.3, 42.9, 47.7, 66.3, 99.1, 108.3, 117.2, 117.6, 155.2, 168.7, 169.1. HRMS calcd for C27H30ClN5O3 [M + H]+
120.7, 121.1, 124.8, 125.3, 128.7, 134.4, 134.8, 149.1, 149.7, 508.2071 found 508.2084.
152.0, 155.4, 168.6, 169.0. HRMS calcd for C25H25ClN4O3 [M +
H]+ 465.1649 found 465.1654.
2-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-5-(4-(2-hydroxyethyl)
piperazin-1-yl)isoindoline-1,3-dione (4t). Yield 85%; dark brown
solid; mp 93–94 ꢁC; 1H NMR (400 MHz, CDCl3) d 1.33–1.39 (m, 4H,
2-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-5-morpholinoiso-
indoline-1,3-dione (4p). Yield 89%; yellow solid; mp 177–178 ꢁC; 2ꢂ –CH2–); 1.75–1.88 (m, 4H, 2ꢂ –CH2–); 2.60 (t, J ¼ 5.3 Hz, 2H,
1H NMR (500 MHz, CDCl3) d 1.39–1.48 (m, 4H, 2ꢂ –CH2–); 1.60– –CH2–); 2.65 (t, J ¼ 4.8 Hz, 4H, 2ꢂ –CH2–); 3.33 (t, J ¼ 6.5 Hz, 2H,
1.69 (m, 4H, 2ꢂ –CH2–); 3.35–3.42 (m, 6H, 3ꢂ –CH2–); 3.76 (t, J –CH2–); 3.40 (t, J ¼ 4.9 Hz, 4H, 2ꢂ –CH2–); 3.65 (t, J ¼ 5.3 Hz, 2H,
¼ 6.2 Hz, 2H, –CH2–); 3.86 (t, J ¼ 4.5 Hz, 4H, 2ꢂ –CH2–); 5.28 (s, –CH2–); 3.72 (t, J ¼ 6.5 Hz, 2H, –CH2–); 6.35 (d, J ¼ 5.4 Hz, 1H, Ar–
1H, NH-exchangeable with D2O); 6.40 (d, J ¼ 5.3 Hz, 1H, Ar–H); H); 7.01 (d, 8.4 Hz, 1H, Ar–H); 7.22 (s, 1H, Ar–H); 7.32 (d, J ¼ 8.9 Hz,
7.02 (d, J ¼ 8.3 Hz, 1H, Ar–H); 7.25 (s, 1H, Ar–H); 7.35 (d, J ¼ 1H, Ar–H); 7.61 (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.71 (d, J ¼ 9.0 Hz, 1H,
8.8 Hz, 1H, Ar–H); 7.66 (d, J ¼ 8.3 Hz, 1H, Ar–H); 7.76 (d, J ¼ Ar–H); 7.90 (s, 1H, Ar–H); 8.45 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR
8.8 Hz, 1H, Ar–H); 7.93 (s, 1H, Ar–H); 8.53 (d, J ¼ 5.2 Hz, 1H, Ar– (100 MHz, CDCl3) d 24.4, 25.5, 26.5, 26.7, 28.3, 28.5, 37.0, 42.7, 47.4,
H); 13C NMR (125 MHz, CDCl3) d 25.5, 26.4, 28.7, 28.9, 37.2, 52.3, 57.5, 59.4, 99.0, 108.3, 117.0, 117.4, 120.1, 121.4, 124.6, 125.2,
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128.7, 134.4, 134.6, 149.0, 149.8, 152.0, 155.1, 168.4, 169.0. HRMS 2H, –CH2–); 3.00–3.05 (m, 2H, –CH2–); 3.20–3.25 (m, 2H, –CH2–);
calcd for C29H34ClN5O3 [M + H]+ 536.2384 found 536.2376.
4.13 (s, 2H, –CH2–); 6.44 (d, J ¼ 5.6 Hz, 1H, Ar–H); 7.38–7.42 (m, 2H,
Ar–H + NH-exchangeable with D2O); 7.74 (d, J ¼ 2.2 Hz, 1H, Ar–H);
7.80–7.86 (m, 4H, Ar–H); 8.16 (t, J ¼ 5.6 Hz, 1H, NH-exchangeable
with D2O); 8.25 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.34 (d, J ¼ 5.5 Hz, 1H,
Ar–H); 13C NMR (100 MHz, DMSO-d6) d 26.5, 26.7, 28.2, 29.4, 39.1,
40.6, 42.9, 99.1, 117.8, 123.6, 124.7, 127.8, 132.3, 134.2, 135.0, 148.8,
150.9, 151.7, 166.3, 168.1. HRMS calcd for C25H25ClN4O3 [M + H]+
465.1649 found 465.1629.
N-(8-((7-Chloroquinolin-4-yl)amino)octyl)-2-(1,3-dioxoisoindolin-
2-yl)acetamide (7d). Yield 76%; white solid; mp 101–102 ꢁC; 1H NMR
(500 MHz, DMSO-d6) d 1.22–1.41 (m, 12H, 6ꢂ –CH2–); 3.03–3.07 (m,
2H, –CH2–); 3.22–3.26 (m, 2H, –CH2–); 4.17 (s, 2H, –CH2–); 6.45 (d, J
¼ 5.3 Hz, 1H, Ar–H); 7.29 (t, J ¼ 5.3 Hz, 1H, NH-exchangeable with
D2O); 7.43 (dd, J ¼ 2.3, 8.9 Hz, 1H, Ar–H); 7.77 (d, J ¼ 2.3 Hz, 1H, Ar–
H); 7.84–7.90 (m, 4H, Ar–H); 8.18 (t, J ¼ 5.6 Hz, 1H, NH-
exchangeable with D2O); 8.27 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.38 (d, J
¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6) d 26.4, 26.6,
28.2, 28.4, 29.3, 29.6, 37.8, 40.6, 42.8, 99.2, 117.9, 123.4, 124.3, 127.9,
General procedure for synthesis of amide linked substituted
isoindoline-1,3-dione-4-aminoquinolines (7a–r, 8a–r)
Synthesis of C-5 substituted 2-(1,3-dioxoisoindolin-2-yl)acetic
acid/3-(1,3-dioxoisoindolin-2-yl)propanoic
acid/4-(1,3-
dioxoisoindolin-2-yl)butanoic acid (6): C-4 substituted phthalic
anhydride (1 mmol), amino acids (1.2 mmol) and triethylamine
(Et3N) (1.2 mmol) were mixed in toluene and the reaction mixture
was reuxed for 6 h. The progress of the reaction was monitored
by thin layer chromatography (TLC). Toluene was evaporated
under reduced pressure and the solid residue was stirred with 1
N-HCl in ice-cold water. The resulted white powder was ltered,
dried and used for subsequent step without any purication.
Synthesis of C-5 substituted N-(2-((7-chloroquinolin-4-yl)amino)
alkyl)-2-(1,3-dioxoisoindolin-2-yl)alkylamides (7a–r)
1.0 mmol of C-5 substituted (1,3-dioxoisoindolin-2-yl)acetic 132.1, 134.2, 135.2, 148.7, 150.6, 151.4, 166.1, 168.0. HRMS calcd for
acid, N-ethyl-N-dimethylaminopropyl carbodiimide (EDC) (1.1 C27H29ClN4O3 [M + H]+ 493.1962 found 493.1956.
mmol), hydroxybenzotriazole (HOBt) (1.2 mmol) and N,N-dii-
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-3-(1,3-dioxoisoindolin-
sopropylethylamine (2.0 mmol) were mixed in minimum DMF 2-yl)propanamide (7e). Yield 81%; white solid; mp 182–183 ꢁC; 1H
and the obtained mixture was stirred for 5 min. Then, 4- NMR (400 MHz, DMSO-d6) d 2.42 (t, J ¼ 7.2 Hz, 2H, –CH2–); 2.25–
aminoquinoline-diamines (1.0 mmol) was added to the reaction 2.30 (m, 4H, 2ꢂ –CH2–); 3.75 (t, J ¼ 7.4 Hz, 2H, –CH2–); 6.56 (d, J
mixture and the stirring was continued for 5 h. The reaction end ¼ 5.8 Hz, 1H, Ar–H); 7.45 (dd, J ¼ 2.0, 9.0 Hz, 1H, Ar–H); 7.70–
was proved by thin layer chromatography (TLC). Then, DMF was 7.74 (m, 4H, Ar–H); 7.79 (d, J ¼ 2.3 Hz, 1H, Ar–H); 7.93 (t, J ¼
evaporated using rotary evaporator and cold water (20 mL) was 5.6 Hz, 1H, NH-exchangeable with D2O); 8.17 (d, J ¼ 9.1 Hz, 1H,
added, and solid precipitates obtained were ltered and washed Ar–H); 8.29 (t, J ¼ 5.4 Hz, 1H, NH-exchangeable with D2O); 8.40 (t,
with cold water. The crude product was recrystallized in abso- J ¼ 5.8 Hz, 1H, Ar–H); 13C NMR (100 MHz, DMSO-d6) d 34.6, 34.9,
lute ethanol.
37.6, 42.9, 99.0, 117.2, 123.4, 124.8, 125.4, 126.7, 132.0, 134.7,
135.3, 146.2, 149.6, 152.2, 168.1, 170.9. HRMS calcd for
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-2-(1,3-dioxoisoindolin-
2-yl)acetamide (7a). Yield 82%; white solid; mp 189–190 ꢁC; 1H NMR C22H19ClN4O3 [M + H]+ 423.1179 found 423.1161.
(400 MHz, DMSO-d6) d 3.31 (s, 4H, 2ꢂ –CH2–); 4.18 (s, 2H, –CH2–);
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-3-(1,3-dioxoisoindolin-
1
ꢁ
6.50 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.33 (t, J ¼ 5.0 Hz, 1H, NH- 2-yl)propanamide (7f). Yield 77%; white solid; mp 172–173 C; H
exchangeable with D2O); 7.38 (dd, J ¼ 1.8, 9.0 Hz, 1H, Ar–H); 7.74 NMR (400 MHz, DMSO-d6) d 1.23–1.33 (m, 4H, 2ꢂ –CH2–); 2.41 (t, J
(d, J ¼ 2.0 Hz, 1H, Ar–H); 7.82–7.88 (m, 4H, Ar–H); 8.11 (d, J ¼ ¼ 7.1 Hz, 2H, –CH2–); 3.05–3.14 (m, 2H, –CH2–); 3.22–3.27 (m, 2H,
9.0 Hz, 1H, Ar–H); 8.36 (d, J ¼ 5.0 Hz, 1H, Ar–H); 8.45 (t, J ¼ 5.6 Hz, –CH2–); 3.73 (t, J ¼ 7.2 Hz, 2H, –CH2–); 6.45 (d, J ¼ 5.4 Hz, 1H, Ar–H);
1H, NH-exchangeable with D2O); 13C NMR (100 MHz, DMSO-d6) 7.32 (t, J ¼ 5.2 Hz, 1H, NH-exchangeable with D2O); 7.43 (dd, J ¼ 2.2,
d 37.9, 40.7, 42.3, 99.1, 117.9, 123.7, 124.4, 124.6, 128.0, 132.2, 133.9, 8.9 Hz, 1H, Ar–H); 7.74 (d, J ¼ 2.2 Hz, 1H, Ar–H); 7.83–7.91 (m, 4H,
135.1, 149.5, 150.5, 152.4, 167.2, 168.0. HRMS calcd for Ar–H); 8.19–8.28 (m, 2H, Ar–H + NH-exchangeable with D2O); 8.38
C21H17ClN4O3 [M + H]+ 409.1023 found 409.1041.
(d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (100 MHz, DMSO-d6) d 25.4, 27.1,
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-2-(1,3-dioxoisoindolin- 34.6, 38.2, 40.8, 42.2, 99.2, 117.5, 123.6, 124.3, 124.8, 128.3, 132.5,
1
ꢁ
2-yl)acetamide (7b). Yield 81%; white solid; mp 129–130 C; H 133.7, 135.2, 149.6, 150.2, 152.6, 168.1, 170.8. HRMS calcd for
NMR (400 MHz, DMSO-d6) d 0.96–1.29 (m, 4H, 2ꢂ –CH2–); 3.08– C24H23ClN4O3 [M + H]+ 451.1492 found 451.1466.
3.15 (m, 2H, –CH2–); 3.25–3.29 (m, 2H, –CH2–); 4.16 (s, 2H, –CH2–
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-3-(1,3-dioxoisoindolin-
); 6.46 (d, J ¼ 5.5 Hz, 1H, Ar–H); 7.33 (t, J ¼ 5.2 Hz, 1H, NH- 2-yl)propanamide (7g). Yield 79%; white solid; mp 122–123 ꢁC; 1H
exchangeable with D2O); 7.42 (dd, J ¼ 2.4, 9.0 Hz, 1H, Ar–H); NMR (400 MHz, DMSO-d6) 1.29–1.40 (m, 6H, 3ꢂ –CH2–); 1.55–1.63
7.76 (d, J ¼ 2.3 Hz, 1H, Ar–H); 7.83–7.90 (m, 4H, Ar–H); 8.20–8.30 (m, 2H, –CH2–); 2.40 (t, J ¼ 7.2 Hz, 2H, –CH2–); 3.01–3.07 (m, 2H,
(m, 2H, Ar–H + NH-exchangeable with D2O); 8.37 (d, J ¼ 5.4 Hz, –CH2–); 3.21–3.27 (m, 2H, –CH2–); 3.72 (t, J ¼ 7.2 Hz, 2H, –CH2–);
1H, Ar–H); 13C NMR (100 MHz, DMSO-d6) d 25.4, 27.2, 37.2, 40.2, 6.44 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.30 (t, J ¼ 5.2 Hz, 1H, NH-
42.1, 99.2, 117.8, 123.7, 124.3, 124.7, 128.1, 132.2, 133.8, 135.2, exchangeable with D2O); 7.42 (dd, J ¼ 2.2, 9.0 Hz, 1H, Ar–H); 7.73
149.4, 150.4, 152.5, 167.0, 168.1. HRMS calcd for C23H21ClN4O3 (d, J ¼ 2.1 Hz, 1H, Ar–H); 7.83–7.92 (m, 4H, Ar–H); 8.20–8.29 (m, 2H,
[M + H]+ 437.1336 found 437.1323.
Ar–H + NH-exchangeable with D2O); 8.35 (d, J ¼ 5.2 Hz, 1H, Ar–H);
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-2-(1,3-dioxoisoindolin- 13C NMR (100 MHz, DMSO-d6) d 26.4, 26.7, 28.3, 29.1, 34.6, 39.4,
2-yl)acetamide (7c). Yield 85%; white solid; mp 110–111 ꢁC; 1H NMR 40.8, 42.2, 99.1, 117.7, 123.6, 124.2, 124.8, 128.4, 132.4, 133.7, 135.1,
(400 MHz, DMSO-d6) d 1.32–1.41 (m, 6H, 3ꢂ –CH2–); 1.57–1.64 (m,
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149.5, 150.1, 152.3, 168.1, 170.7. HRMS calcd for C26H27ClN4O3 [M + –CH2–); 3.20–3.25 (m, 2H, –CH2–); 3.54 (t, J ¼ 7.2 Hz, 2H, –CH2–);
H]+ 479.1805 found 479.1814.
6.44 (d, J ¼ 5.2 Hz, 1H, Ar–H); 7.28 (t, J ¼ 5.3 Hz, 1H, NH-
exchangeable with D2O); 7.44 (dd, J ¼ 2.2, 8.9 Hz, 1H, Ar–H); 7.75
N-(8-((7-Chloroquinolin-4-yl)amino)octyl)-3-(1,3-dioxoisoindolin-
1
2-yl)propanamide (7h). Yield 70%; white solid; mp 85–86 ꢁC; H (d, J ¼ 2.3 Hz, 1H, Ar–H); 7.83–7.90 (m, 4H, Ar–H); 8.19 (d, J ¼
NMR (400 MHz, DMSO-d6) 1.20–1.40 (m, 12H, 6ꢂ –CH2–); 2.41 (t, J 5.4 Hz, 1H, Ar–H); 8.27 (d, J ¼ 8.9 Hz, 1H, Ar–H); 8.40 (t, J ¼ 5.3 Hz,
¼ 7.1 Hz, 2H, –CH2–); 3.02–3.07 (m, 2H, –CH2–); 3.21–3.26 (m, 2H, 1H, NH-exchangeable with D2O); 13C NMR (125 MHz, DMSO-d6)
–CH2–); 3.71 (t, J ¼ 7.2 Hz, 2H, –CH2–); 6.43 (d, J ¼ 5.3 Hz, 1H, Ar–H); d 24.5, 26.4, 26.7, 28.1, 28.5, 29.4, 29.8, 33.3, 37.8, 40.5, 43.4, 99.1,
7.31 (t, J ¼ 5.4 Hz, 1H, NH-exchangeable with D2O); 7.41 (dd, J ¼ 2.1, 115.9, 119.34, 123.4, 126.6, 127.2, 132.1, 134.6, 138.7, 138.8, 143.3,
9.0 Hz, 1H, Ar–H); 7.75 (d, J ¼ 2.0 Hz, 1H, Ar–H); 7.85–7.94 (m, 4H, 156.3, 168.2, 172.6. HRMS calcd for C29H33ClN4O3 [M + H]+ 521.2275
Ar–H); 8.20–8.30 (m, 2H, Ar–H + NH-exchangeable with D2O); 8.34 found 521.2258.
(d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (100 MHz, DMSO-d6) d 26.2, 26.6,
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-2-(5-uoro-1,3-
28.2, 28.5, 29.1, 29.5, 34.6, 37.8, 40.5, 42.2, 99.2, 117.5, 123.8, 124.2, dioxoisoindolin-2-yl)acetamide (7m). Yield 81%; white solid;
1
124.9, 128.5, 132.4, 133.9, 135.0, 149.5, 150.0, 152.5, 168.3, 170.9. mp 192–193 ꢁC; H NMR (DMSO-d6, 500 MHz): 3.31 (s, 4H, 2ꢂ
HRMS calcd for C28H31ClN4O3 [M + H]+ 507.2118 found 507.2129.
–CH2–); 4.17 (s, 2H, –CH2–); 6.51 (d, J ¼ 5.5 Hz, 1H, Ar–H); 7.37–
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-4-(1,3-dioxoisoindolin-
7.42 (m, 2H, Ar–H + NH-exchangeable with D2O); 7.64–7.69 (m,
1
ꢁ
2-yl)butanamide (7i). Yield 83%; white solid; mp 177–178 C; H 1H, Ar–H); 7.75 (d, J ¼ 2.2 Hz, 1H, Ar–H); 7.77–7.80 (m, 1H, Ar–
NMR (500 MHz, DMSO-d6) d 1.77–1.83 (m, 2H, –CH2–); 2.12 (t, J ¼ H); 7.93–7.96 (m, 1H, Ar–H); 8.13 (d, J ¼ 9.0 Hz, Ar–H); 8.37 (d, J
7.5 Hz, 2H, –CH2–); 3.32 (t, J ¼ 6.0 Hz, 2H, –CH2–); 3.52–3.57 (m, 4H, ¼ 5.5 Hz, Ar–H); 8.45 (t, J ¼ 5.6 Hz, 1H, NH-exchangeable with
2ꢂ –CH2–); 6.89 (d, J ¼ 7.1 Hz, 1H, Ar–H); 7.77 (dd, J ¼ 2.2, 9.1 Hz, D2O); 13C NMR (125 MHz, DMSO-d6) d 36.7, 41.3, 42.5, 99.1,
1H, Ar–H); 7.81–7.86 (m, 4H, Ar–H); 8.00 (d, J ¼ 2.1 Hz, 1H, Ar–H); 111.3 (d, J ¼ 22.9 Hz), 117.8, 121.5 (d, J ¼ 23.7 Hz), 124.8, 125.1,
8.16 (t, J ¼ 5.3 Hz, 1H, NH-exchangeable with D2O); 8.53–8.57 (m, 126.7 (d, J ¼ 9.6 Hz), 127.9, 128.5 (d, J ¼ 1.9 Hz), 133.4, 135.1 (d, J
2H, Ar–H); 9.54 (t, J ¼ 5.9 Hz, 1H, NH-exchangeable with D2O); 13
C
¼ 9.4 Hz), 149.7, 150.6, 152.5, 166.2 (d, J ¼ 252.3 Hz), 166.7 (d, J
NMR (125 MHz, DMSO-d6) d 24.3, 33.1, 37.5, 37.6, 43.2, 98.9, 115.9, ¼ 2.3 Hz), 167.3, 169.7. HRMS calcd for C21H16ClFN4O3 [M + H]+
119.4, 123.4, 126.1, 127.3, 132.0, 134.8, 138.4, 138.9, 143.3, 156.1, 427.0929 found 427.0935.
168.3, 172.6. HRMS calcd for C23H21ClN4O3 [M + H]+ 437.1336 found
437.1321.
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-2-(5-uoro-1,3-
dioxoisoindolin-2-yl)acetamide (7n). Yield 85%; white solid; mp
1
ꢁ
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-4-(1,3-dioxoisoindolin- 140–141 C; H NMR (DMSO-d6, 500 MHz): 1.50–1.56 (m, 2H,
1
ꢁ
2-yl)butanamide (7j). Yield 74%; white solid; mp 145–146 C; H –CH2–); 1.62–1.68 (m, 2H, –CH2–); 3.11–3.15 (m, 2H, –CH2–);
NMR (500 MHz, DMSO-d6) d 1.22–1.34 (m, 4H, 2ꢂ –CH2–); 1.76–1.83 3.27–3.31 (m, 2H, –CH2–); 4.18 (s, 2H, –CH2–); 6.50 (d, J ¼
(m, 2H, –CH2–); 2.11 (t, J ¼ 7.1 Hz, 2H, –CH2–); 3.08–3.15 (m, 2H, 5.6 Hz, 1H, Ar–H); 7.45–7.47 (m, 2H, Ar–H + NH-exchangeable
–CH2–); 3.25–3.29 (m, 2H, –CH2–); 3.56 (t, J ¼ 7.2 Hz, 2H, –CH2–); with D2O); 7.68–7.72 (m, 1H, Ar–H); 7.78 (d, J ¼ 2.3 Hz, 1H,
6.85 (d, J ¼ 7.1 Hz, 1H, Ar–H); 7.76 (dd, J ¼ 2.0, 9.0 Hz, 1H, Ar–H); Ar–H); 7.81–7.83 (m, 1H, Ar–H); 7.97–7.99 (m, 1H, Ar–H); 8.25 (t,
7.80–7.86 (m, 4H, Ar–H); 8.01 (d, J ¼ 2.1 Hz, 1H, Ar–H); 8.14 (t, J ¼ J ¼ 5.7 Hz, NH-exchangeable with D2O); 8.29 (d, J ¼ 9.0 Hz, Ar–
5.4 Hz, 1H, NH-exchangeable with D2O); 8.54–8.59 (m, 2H, Ar–H); H); 8.39 (d, J ¼ 5.5 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6)
8.85 (t, J ¼ 5.5 Hz, 1H, NH-exchangeable with D2O); 13C NMR (125 d 25.7, 26.8, 35.2, 39.3, 42.9, 99.0, 111.7 (d, J ¼ 23.3 Hz), 117.7,
MHz, DMSO-d6) d 24.4, 25.3, 27.5, 33.4, 37.6, 40.9, 43.2, 99.1, 115.7, 121.5 (d, J ¼ 23.4 Hz), 124.4, 124.8, 126.6 (d, J ¼ 9.6 Hz), 127.9,
119.3, 123.4, 126.4, 127.3, 132.1, 134.8, 138.5, 138.8, 143.4, 156.1, 128.3 (d, J ¼ 1.8 Hz), 133.9, 135.2 (d, J ¼ 9.4 Hz), 149.1, 150.4,
168.2, 172.4. HRMS calcd for C25H25ClN4O3 [M + H]+ 465.1649 found 152.2, 166.1 (d, J ¼ 251.6 Hz), 166.9 (d, J ¼ 2.3 Hz), 167.4, 169.8.
465.1633.
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-4-(1,3-dioxoisoindolin- 455.1265.
2-yl)butanamide (7k). Yield 75%; white solid; mp 158–159 C; H
HRMS calcd for C23H20ClFN4O3 [M + H]+ 455.1242 found
1
ꢁ
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-2-(5-uoro-1,3-
NMR (500 MHz, DMSO-d6) d 1.18–1.25 (m, 2H, –CH2–); 1.27–1.40 dioxoisoindolin-2-yl)acetamide (7o). Yield 84%; white solid; mp
(m, 4H, 2ꢂ –CH2–); 1.61–1.67 (m, 2H, –CH2–); 1.78–1.85 (m, 2H, 131–132 ꢁC; 1H NMR (DMSO-d6, 400 MHz): 1.36–1.44 (m, 4H, 2ꢂ
–CH2–); 2.06–2.10 (m, 2H, –CH2–); 2.91–2.99 (m, 2H, –CH2–); 3.23– –CH2–); 1.54–1.62 (m, 4H, 2ꢂ –CH2–); 3.01–3.07 (m, 2H, –CH2–);
3.27 (m, 2H, –CH2–); 3.57 (t, J ¼ 7.1 Hz, 2H, –CH2–); 6.46 (d, J ¼ 3.22–3.25 (m, 2H, –CH2–); 4.17 (s, 2H, –CH2–); 6.39 (d, J ¼
5.4 Hz, 1H, Ar–H); 7.32 (t, J ¼ 5.55 Hz, 1H, NH-exchangeable with 5.3 Hz, 1H, Ar–H); 7.30 (t, J ¼ 5.4 Hz, NH-exchangeable with
D2O); 7.44 (dd, J ¼ 2.1, 8.9 Hz, 1H, Ar–H); 7.71 (d, J ¼ 5.5 Hz, 1H, Ar– D2O); 7.35 (dd, J ¼ 2.1, 9.0 Hz, 1H, Ar–H); 7.54–7.59 (m, 1H, Ar–
H); 7.76 (d, J ¼ 2.3 Hz, 1H, Ar–H); 7.81–7.86 (m, 4H, Ar–H); 8.28 (d, J H); 7.69–7.74 (m, 2H, Ar–H); 7.88–7.90 (m, 1H, Ar–H); 7.96 (t, J ¼
¼ 9.0 Hz, 1H, Ar–H); 8.38 (t, J ¼ 5.5 Hz, 1H, NH-exchangeable with 5.5 Hz, NH-exchangeable with D2O); 8.22 (d, J ¼ 9.0 Hz, Ar–H);
D2O); 13C NMR (125 MHz, DMSO-d6) d 24.5, 26.4, 26.9, 28.2, 29.7, 8.31 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (100 MHz, DMSO-d6)
33.5, 38.4, 40.4, 43.5, 99.2, 115.6, 119.3, 123.5, 126.4, 127.2, 132.0, d 26.5, 26.9, 28.5, 29.6, 39.5, 40.9, 42.5, 99.1, 111.4 (d, J ¼ 23.7
134.9, 138.5, 138.9, 143.3, 156.2, 168.1, 172.2. HRMS calcd for Hz), 117.7, 121.9 (d, J ¼ 23.7 Hz), 124.9, 125.4, 126.5 (d, J ¼ 9.7
C27H29ClN4O3 [M + H]+ 493.1962 found 4931951.
Hz), 127.8, 128.2 (d, J ¼ 1.9 Hz), 133.7, 135.1 (d, J ¼ 9.7 Hz),
149.6, 150.7, 152.3, 166.0 (d, J ¼ 252.3 Hz), 166.8 (d, J ¼ 2.4 Hz),
N-(8-((7-Chloroquinolin-4-yl)amino)octyl)-4-(1,3-dioxoisoindolin-
2-yl)butanamide (7l). Yield 78%; white solid; mp 152–153 C; H 167.2, 169.6. HRMS calcd for C25H24ClFN4O3 [M + H]+ 483.1555
1
ꢁ
NMR (500 MHz, DMSO-d6) d 1.20–1.39 (m, 12H, 6ꢂ –CH2–); 1.75– found 483.1561.
1.84 (m, 2H, –CH2–); 2.07–2.11 (m, 2H, –CH2–); 3.02–3.06 (m, 2H,
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methylpyrrolidin-2-one) and secondary amines (1.2 mmol).
Aer sealing with a PTFE cap, the vessel was heated to 160 ꢁC for
5 min in the microwave reactor and the completion was ascer-
tained using TLC. Aer completion, the contents were poured
in water (20 mL) resulting in the precipitation of the desired
product. The yellow product obtained was ltered and re-
crystallized using absolute ethanol.
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-3-(5-uoro-1,3-
dioxoisoindolin-2-yl)propanamide (7p). Yield 81%; white solid;
mp 183–184 ꢁC; 1H NMR (DMSO-d6, 400 MHz): 2.40 (t, J ¼
7.2 Hz, 2H, –CH2–); 3.00–3.09 (m, 4H, 2ꢂ –CH2–); 3.73 (t, J ¼
7.1 Hz, 2H, –CH2–); 6.41 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.29 (t, J ¼
5.5 Hz, NH-exchangeable with D2O); 7.41 (dd, J ¼ 2.1, 9.0 Hz,
1H, Ar–H); 7.56–7.62 (m, 1H, Ar–H); 7.70–7.74 (m, 2H, Ar–H);
7.84–7.88 (m, 1H, Ar–H); 7.99 (t, J ¼ 5.4 Hz, NH-exchangeable
with D2O); 8.22 (d, J ¼ 9.1 Hz, Ar–H); 8.35 (d, J ¼ 5.5 Hz, 1H,
Ar–H); 13C NMR (100 MHz, DMSO-d6) d 34.5, 37.9, 40.8, 42.4,
99.2, 111.3 (d, J ¼ 23.2 Hz), 117.5, 121.2 (d, J ¼ 23.4 Hz), 124.4,
124.8, 126.5 (d, J ¼ 9.5 Hz), 127.8, 128.2 (d, J ¼ 1.8 Hz), 133.7,
135.0 (d, J ¼ 9.5 Hz), 149.6, 150.3, 152.2, 166.1 (d, J ¼ 251.9 Hz),
166.5 (d, J ¼ 2.3 Hz), 167.1, 169.9. HRMS calcd for C27H29ClN4O3
[M]+ 492.1928 found 4921941. HRMS calcd for C22H18ClFN4O3
[M + H]+ 441.1085 found 441.1097.
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-2-(5-morpholino-
1,3-dioxoisoindolin-2-yl)acetamide (8a). Yield 76%; yellow solid;
1
ꢁ
mp 216–217 C; H NMR (500 MHz, DMSO-d6) d 3.30–3.32 (m,
6H, 3ꢂ –CH2–); 3.59–3.63 (m, 2H, –CH2–); 3.74–3.76 (m, 4H, 2ꢂ
–CH2–); 4.12 (s, 2H, –CH2–); 6.90 (d, J ¼ 7.1 Hz, 1H, Ar–H); 7.25
(dd, J ¼ 2.3, 8.5 Hz, 1H, Ar–H); 7.32 (d, J ¼ 2.2 Hz, 1H, Ar–H);
7.66 (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.77 (dd, J ¼ 2.0, 9.0 Hz, 1H, Ar–
H); 8.05 (d, J ¼ 2.1 Hz, 1H, Ar–H); 8.55–8.57 (m, 3H, Ar–H); 9.55
(t, J ¼ 5.9 Hz, 1H, NH-exchangeable with D2O); 13C NMR (125
MHz, DMSO-d6) d 39.1, 42.7, 47.6, 48.8, 66.5, 99.1, 108.3, 117.8,
118.1, 120.2, 124.5, 124.6, 125.1, 127.9, 133.5, 134.6, 149.4,
150.5, 152.3, 155.7, 166.4, 167.7, 168.4, 174.1. HRMS calcd for
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-3-(5-uoro-1,3-
dioxoisoindolin-2-yl)propanamide (7q). Yield 76%; white solid;
1
mp 177–178 ꢁC; H NMR (DMSO-d6, 400 MHz): 1.38–1.45 (m,
C
25H24ClN5O4 [M + H]+ 494.1550 found 494.1564.
2H, –CH2–); 1.51–1.58 (m, 2H, –CH2–); 2.38 (t, J ¼ 7.2 Hz, 2H,
–CH2–); 2.98–3.03 (m, 2H, –CH2–); 3.15–3.20 (m, 2H, –CH2–);
3.72 (t, J ¼ 7.3 Hz, 2H, –CH2–); 6.39 (d, J ¼ 5.4 Hz, 1H, Ar–H);
7.28 (t, J ¼ 5.4 Hz, NH-exchangeable with D2O); 7.39 (dd, J ¼ 2.3,
9.1 Hz, 1H, Ar–H); 7.54–7.59 (m, 1H, Ar–H); 7.69–7.72 (m, 2H,
Ar–H); 7.85–7.88 (m, 1H, Ar–H); 7.98 (t, J ¼ 5.5 Hz, NH-
exchangeable with D2O); 8.21 (d, J ¼ 9.0 Hz, Ar–H); 8.33 (d, J
¼ 5.4 Hz, 1H, Ar–H); 13C NMR (100 MHz, DMSO-d6) d 25.6, 27.1,
34.4, 35.1, 38.6, 42.5, 99.1, 111.4 (d, J ¼ 23.5 Hz), 117.9, 121.5 (d,
J ¼ 23.5 Hz), 124.5, 124.6, 126.2 (d, J ¼ 9.6 Hz), 127.8, 128.3 (d, J
¼ 1.7 Hz), 133.9, 135.1 (d, J ¼ 9.5 Hz), 149.4, 150.6, 152.3, 166.2
(d, J ¼ 251.7 Hz), 166.8 (d, J ¼ 2.4 Hz), 167.2, 169.8. HRMS calcd
for C24H22ClFN4O3 [M + H]+ 469.1398 found 469.1387.
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-2-(5-morpholino-
1,3-dioxoisoindolin-2-yl)acetamide (8b). Yield 79%; yellow
solid; mp 174–175 ꢁC; 1H NMR (500 MHz, DMSO-d6) d 1.51–1.56
(m, 2H, –CH2–); 1.63–1.69 (m, 2H, –CH2–); 3.07–3.011 (m, 2H,
–CH2–); 3.25–3.28 (m, 2H, –CH2–); 3.39–3.42 (m, 4H, 2ꢂ –CH2–);
3.70–3.74 (m, 4H, 2ꢂ –CH2–); 4.15 (s, 2H, –CH2–); 6.46 (d, J ¼
5.3 Hz, 1H, Ar–H); 7.25 (dd, J ¼ 2.2, 8.7 Hz, 1H, Ar–H); 7.28 (t, J ¼
5.4 Hz, 1H, NH-exchangeable with D2O); 7.31 (d, J ¼ 2.2 Hz, 1H,
Ar–H); 7.45 (dd, J ¼ 2.0, 9.0 Hz, 1H, Ar–H); 7.68 (d, J ¼ 8.8 Hz,
1H, Ar–H); 7.79 (d, J ¼ 2.1 Hz, 1H, Ar–H); 8.16 (t, J ¼ 5.5 Hz, 1H,
NH-exchangeable with D2O); 8.27 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.39
(d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6) d 25.4,
27.6, 37.9, 40.6, 42.7, 47.4, 66.3, 99.1, 108.5, 117.7, 118.2, 120.3,
124.5, 124.7, 125.2, 127.7, 133.9, 134.5, 149.6, 150.5, 152.7,
155.6, 166.4, 167.9, 168.2, 174.1. HRMS calcd for C27H28ClN5O4
[M + H]+ 522.1863 found 522.1878.
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-3-(5-uoro-1,3-
dioxoisoindolin-2-yl)propanamide (7r). Yield 77%; white solid;
1
mp 138–139 ꢁC; H NMR (DMSO-d6, 400 MHz): 1.32–1.39 (m,
6H, 3ꢂ –CH2–); 1.54–1.63 (m, 2H, –CH2–); 2.39 (t, J ¼ 7.1 Hz, 2H,
–CH2–); 3.00–3.05 (m, 2H, –CH2–); 3.19–3.24 (m, 2H, –CH2–);
3.71 (t, J ¼ 7.2 Hz, 2H, –CH2–); 6.38 (d, J ¼ 5.3 Hz, 1H, Ar–H);
7.29 (t, J ¼ 5.4 Hz, NH-exchangeable with D2O); 7.37 (dd, J ¼ 2.2,
9.0 Hz, 1H, Ar–H); 7.53–7.59 (m, 1H, Ar–H); 7.68–7.73 (m, 2H,
Ar–H); 7.86–7.89 (m, 1H, Ar–H); 7.95 (t, J ¼ 5.4 Hz, NH-
exchangeable with D2O); 8.20 (d, J ¼ 9.1 Hz, Ar–H); 8.32 (d, J
¼ 5.3 Hz, 1H, Ar–H); 13C NMR (100 MHz, DMSO-d6) d 26.7, 26.9,
28.3, 29.5, 34.1, 39.3, 40.7, 42.4, 99.0, 111.5 (d, J ¼ 23.4 Hz),
117.5, 121.8 (d, J ¼ 23.7 Hz), 124.8, 125.3, 126.1 (d, J ¼ 9.7 Hz),
127.9, 128.2 (d, J ¼ 1.9 Hz), 133.8, 135.0 (d, J ¼ 9.7 Hz), 149.5,
150.5, 152.2, 166.1 (d, J ¼ 251.6 Hz), 166.9 (d, J ¼ 2.5 Hz), 167.3,
169.7. HRMS calcd for C26H26ClFN4O3 [M + H]+ 497.1711 found
497.1723.
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-2-(5-morpholino-
1,3-dioxoisoindolin-2-yl)acetamide (8c). Yield 81%; yellow solid;
1
ꢁ
mp 160–161 C; H NMR (500 MHz, DMSO-d6) d 1.30–1.45 (m,
6H, 3ꢂ –CH2–); 1.64–1.67 (m, 2H, –CH2–); 3.04–3.09 (m, 2H,
–CH2–); 3.23–3.27 (m, 2H, –CH2–); 3.36–3.39 (m, 4H, 2ꢂ –CH2–);
3.72–3.75 (m, 4H, 2ꢂ –CH2–); 4.12 (s, 2H, –CH2–); 6.45 (d, J ¼
5.4 Hz, 1H, Ar–H); 7.22 (dd, J ¼ 2.4, 8.6 Hz, 1H, Ar–H); 7.27 (t, J ¼
5.5 Hz, 1H, NH-exchangeable with D2O); 7.32 (d, J ¼ 2.3 Hz, 1H,
Ar–H); 7.42 (dd, J ¼ 2.3, 8.9 Hz, 1H, Ar–H); 7.66 (d, J ¼ 8.6 Hz,
1H, Ar–H); 7.77 (d, J ¼ 2.2 Hz, 1H, Ar–H); 8.15 (t, J ¼ 5.6 Hz, 1H,
NH-exchangeable with D2O); 8.26 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.38
(d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6) d 26.4,
26.7, 28.1, 29.4, 39.0, 42.7, 47.5, 48.9, 66.2, 99.0, 108.2, 117.9,
118.0, 120.1, 124.4, 124.5, 125.0, 127.9, 133.7, 134.7, 149.5,
150.5, 152.4, 155.7, 166.5, 167.8, 168.3, 174.2. HRMS calcd for
29H32ClN5O4 [M + H]+ 550.2176 found 550.2188.
General procedure for synthesis of C-5 secondary amine
substituted N-((7-chloroquinolin-4-yl)aminoalkyl)-2-(1,3-
dioxoisoindolin-2-yl)alkylamides 8a–r
C
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-3-(5-morpholino-
1,3-dioxoisoindolin-2-yl)propanamide (8d). Yield 76%; yellow
In a microwave reaction vial was added a solution of C-5 uoro solid; mp 208–209 ꢁC; 1H NMR (400 MHz, DMSO-d6) d 2.38 (t, J
substituted N-((7-chloroquinolin-4-yl)aminoalkyl)-2-(1,3-dioxoi- ¼ 7.3 Hz, 2H, –CH2–); 3.20–3.28 (m, 8H, 4ꢂ –CH2–); 3.67–3.73
soindolin-2-yl)alkylamides (1.0 mmol) in 0.5 mL of NMP (N- (m, 6H, 3ꢂ –CH2–); 6.44 (d, J ¼ 5.6 Hz, 1H, Ar–H); 7.06 (dd, J ¼
8524 | RSC Adv., 2019, 9, 8515–8528
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2.3, 8.4 Hz, 1H, Ar–H); 7.16 (d, J ¼ 2.2 Hz, 1H, Ar–H); 7.25 (t, J ¼
5.1 Hz, 1H, N–H-exchangeable with D2O); 7.36 (dd, J ¼ 2.3,
9.0 Hz, 1H, Ar–H); 7.50 (d, J ¼ 8.6 Hz, 1H, Ar–H); 7.73 (d, J ¼
2.3 Hz, 1H, Ar–H); 8.02 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.24 (t, J ¼
5.5 Hz, 1H, N–H-exchangeable with D2O); 8.35 (d, J ¼ 5.1 Hz, 1H,
Ar–H); 13C NMR (100 MHz, DMSO-d6) d 34.7, 34.8, 37.7, 42.8,
47.4, 66.2, 99.0, 108.0, 117.7, 117.8, 119.9, 124.2, 124.5, 124.7,
127.9, 133.8, 134.4, 149.4, 150.4, 152.3, 155.5, 168.0, 168.3,
170.9. HRMS calcd for C26H26ClN5O4 [M + H]+ 508.1707 found
508.1716.
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-3-(5-morpholino-
1,3-dioxoisoindolin-2-yl)propanamide (8e). Yield 82%; Yellow
solid; mp 158–159 ꢁC; 1H NMR (400 MHz, DMSO-d6) d 1.52–1.57
(m, 2H, –CH2–); 1.61–1.67 (m, 2H, –CH2–); 2.36 (t, J ¼ 7.1 Hz, 2H,
–CH2–); 3.19–3.28 (m, 8H, 4ꢂ –CH2–); 3.65–3.71 (m, 6H, 3ꢂ
–CH2–); 6.42 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.04 (dd, J ¼ 2.2, 8.7 Hz,
1H, Ar–H); 7.14 (d, J ¼ 2.2 Hz, 1H, Ar–H); 7.23 (t, J ¼ 5.3 Hz, 1H,
N–H-exchangeable with D2O); 7.32 (dd, J ¼ 2.2, 8.9 Hz, 1H, Ar–
H); 7.51 (d, J ¼ 8.7 Hz, 1H, Ar–H); 7.71 (d, J ¼ 2.2 Hz, 1H, Ar–H);
8.01 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.25 (t, J ¼ 5.4 Hz, 1H, N–H-
exchangeable with D2O); 8.33 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C
NMR (100 MHz, DMSO-d6) d 25.5, 27.4, 34.6, 34.9, 37.9, 42.9,
47.7, 66.1, 99.1, 108.2, 117.5, 117.9, 119.4, 124.1, 124.6, 124.8,
127.7, 133.6, 134.2, 149.1, 150.2, 152.1, 155.6, 168.1, 168.2,
170.7. HRMS calcd for C28H30ClN5O4 [M + H]+ 536.2020 found
536.2009.
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-3-(5-morpholino-
1,3-dioxoisoindolin-2-yl)propanamide (8f). Yield 78%; yellow
solid; mp 126–127 ꢁC; 1H NMR (400 MHz, DMSO-d6) d 1.31–1.46
(m, 6H, 3ꢂ –CH2–); 1.53–1.56 (m, 2H, –CH2–); 2.35 (t, J ¼ 7.1 Hz,
2H, –CH2–); 3.05–3.09 (m, 2H, –CH2–); 3.23–3.27 (m, 2H, –CH2–
); 3.35–3.39 (m, 4H, 2ꢂ –CH2–); 3.66–3.73 (m, 6H, 3ꢂ –CH2–);
6.41 (d, J ¼ 5.3 Hz, 1H, Ar–H); 7.03 (dd, J ¼ 2.1, 8.6 Hz, 1H, Ar–
H); 7.15 (d, J ¼ 2.1 Hz, 1H, Ar–H); 7.25 (t, J ¼ 5.2 Hz, 1H, N–H-
exchangeable with D2O); 7.33 (dd, J ¼ 2.0, 8.9 Hz, 1H, Ar–H);
7.53 (d, J ¼ 8.8 Hz, 1H, Ar–H); 7.73 (d, J ¼ 2.1 Hz, 1H, Ar–H); 8.03
(d, J ¼ 9.0 Hz, 1H, Ar–H); 8.26 (t, J ¼ 5.3 Hz, 1H, N–H-
exchangeable with D2O); 8.34 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C
NMR (100 MHz, DMSO-d6) d 26.5, 26.9, 28.1, 29.5, 34.6, 38.2,
40.1, 42.8, 47.6, 66.2, 99.2, 108.1, 117.6, 117.8, 119.3, 124.2,
124.7, 124.8, 127.6, 133.7, 134.1, 149.3, 150.1, 152.4, 155.5,
168.1, 168.3, 170.5 HRMS calcd for C30H34ClN5O4 [M + H]+
564.2333 found 564.2326.
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-2-(5-(diethylamino)-
1,3-dioxoisoindolin-2-yl)acetamide (8h). Yield 78%; yellow solid;
1
ꢁ
mp 173–174 C; H NMR (400 MHz, DMSO-d6) d 1.13 (t, 6H, 2ꢂ
–CH3); 1.50–1.57 (m, 2H, –CH2–); 1.62–1.68 (m, 2H, –CH2–); 3.10–
3.14 (m, 2H, –CH2–); 3.27–3.31 (m, 2H, 2ꢂ –CH2–); 3.39–3.43 (m,
4H, 2ꢂ –CH2–); 4.10 (s, 2H, –CH2–); 6.51 (d, J ¼ 5.6 Hz, 1H, Ar–H);
6.92 (d, J ¼ 8.7 Hz, 1H, Ar–H); 6.99 (s, 1H, Ar–H), 7.44–7.50 (m, 2H,
Ar–H + NH-exchangeable with D2O); 7.59 (d, J ¼ 8.5 Hz, 1H, Ar–H);
7.78 (s, 1H, Ar–H), 8.18 (t, J ¼ 5.2 Hz, 1H, NH-exchangeable with
D2O); 8.29 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.39 (d, J ¼ 5.7 Hz, 1H, Ar–H);
13C NMR (100 MHz, DMSO-d6) d 12.5, 25.5, 27.1, 38.8, 41.5, 42.5,
44.8, 99.1, 105.2, 114.8, 116.3, 117.7, 124.5, 124.6, 125.4, 127.1,
127.4, 134.2, 135.3, 150.9, 151.6, 152.3, 166.7, 167.9, 168.6 HRMS
calcd for C27H30ClN5O3 [M + H]+ 508.2071 found 508.2079.
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-2-(5-(diethylamino)-
1,3-dioxoisoindolin-2-yl)acetamide (8i). Yield 79%; yellow solid;
1
ꢁ
mp 158–159 C; H NMR (400 MHz, DMSO-d6) d 1.12 (t, 6H, 2ꢂ
–CH3); 1.32–1.44 (m, 6H, 3ꢂ –CH2–); 1.63–1.67 (m, 2H, –CH2–);
3.07–3.10 (m, 2H, –CH2–); 3.25–3.30 (m, 2H, 2ꢂ –CH2–); 3.37–3.41
(m, 4H, 2ꢂ –CH2–); 4.11 (s, 2H, –CH2–); 6.50 (d, J ¼ 5.4 Hz, 1H, Ar–
H); 6.90 (dd, J ¼ 2.2, 8.8 Hz, 1H, Ar–H); 6.98 (d, J ¼ 2.3 Hz, 1H, Ar–
H), 7.43–7.50 (m, 2H, Ar–H + NH-exchangeable with D2O); 7.54 (d, J
¼ 8.6 Hz, 1H, Ar–H); 7.75 (d, J ¼ 2.2 Hz 1H, Ar–H), 8.20 (t, J ¼
5.3 Hz, 1H, NH-exchangeable with D2O); 8.27 (d, J ¼ 9.0 Hz, 1H, Ar–
H); 8.37 (d, J ¼ 5.4 Hz, 1H, Ar–H);13C NMR (100 MHz, DMSO-d6)
d 12.4, 26.3, 26.9, 28.2, 29.5, 39.2, 41.3, 42.9, 44.6, 99.2, 105.1, 114.8,
116.3, 117.6, 124.7, 124.9, 125.4, 127.3, 127.7, 134.3, 135.3, 150.8,
151.6, 152.4, 166.6, 167.8, 168.7 HRMS calcd for C29H34ClN5O3 [M
+ H]+ 536.2384 found 536.2371.
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-3-(5-(diethylamino)-
1,3-dioxoisoindolin-2-yl)propanamide (8j). Yield 70%; yellow solid;
mp 189–190 ꢁC; 1H NMR (400 MHz, DMSO-d6) d 1.05 (t, J ¼ 7.0 Hz,
6H, 2ꢂ –CH3); 2.37 (t, J ¼ 7.3 Hz, 2H, –CH2); 3.22–3.26 (m, 4H, 2ꢂ
–CH2–); 3.38–3.42 (m, 4H, 2ꢂ –CH2–); 3.69 (t, J ¼ 7.3 Hz, 2H, –CH3);
6.45 (d, J ¼ 5.4 Hz, 1H, Ar–H); 6.76 (dd, J ¼ 2.6, 8.8 Hz, 1H, Ar–H);
6.85 (d, J ¼ 2.6 Hz, 1H, Ar–H), 7.29 (t, J ¼ 5.2 Hz, 1H, NH-
exchangeable with D2O); 7.37 (dd, J ¼ 2.2, 9.0 Hz, 1H, Ar–H);
7.44 (d, J ¼ 8.6 Hz, 1H, Ar–H); 7.73 (d, J ¼ 2.4 Hz 1H, Ar–H), 8.05 (d,
J ¼ 9.0 Hz, 1H, Ar–H); 8.23 (t, J ¼ 5.3 Hz, 1H, NH-exchangeable
with D2O); 8.35 (d, J ¼ 5.0 Hz, 1H, Ar–H); 13C NMR (100 MHz,
DMSO-d6) d 12.6, 34.6, 37.7, 41.1, 42.7, 44.8, 99.0, 105.0, 114.6,
116.2, 117.8, 124.3, 124.5, 124.6, 125.2, 127.8, 133.9, 135.0, 149.3,
150.5, 152.2, 168.1, 168.6, 170.9 HRMS calcd for C26H28ClN5O3 [M
+ H]+ 494.1914 found 494.1902.
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-3-(5-(diethylamino)-
1,3-dioxoisoindolin-2-yl)propanamide (8k). Yield 72%; yellow
solid; mp 161–162 ꢁC; 1H NMR (400 MHz, DMSO-d6) d 1.04 (t, J ¼
7.1 Hz, 6H, 2ꢂ –CH3); 1.52–1.57 (m, 2H, –CH2–); 1.60–1.67 (m, 2H,
–CH2–); 2.35 (t, J ¼ 7.2 Hz, 2H, –CH3); 3.11–3.15 (m, 2H, –CH2–);
3.25–3.30 (m, 2H, –CH2–); 3.37–3.41 (m, 4H, 2ꢂ –CH2–); 3.67 (t, J ¼
7.2 Hz, 2H, –CH3); 6.43 (d, J ¼ 5.3 Hz, 1H, Ar–H); 6.77 (dd, J ¼ 2.4,
8.7 Hz, 1H, Ar–H); 6.84 (d, J ¼ 2.4 Hz, 1H, Ar–H), 7.26 (t, J ¼ 5.4 Hz,
1H, NH-exchangeable with D2O); 7.37 (dd, J ¼ 2.1, 9.0 Hz, 1H, Ar–
H); 7.45 (d, J ¼ 8.7 Hz, 1H, Ar–H); 7.75 (d, J ¼ 2.2 Hz 1H, Ar–H), 8.07
(d, J ¼ 9.0 Hz, 1H, Ar–H); 8.25 (t, J ¼ 5.3 Hz, 1H, NH-exchangeable
with D2O); 8.36 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C NMR (100 MHz,
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-2-(5-(diethylamino)-
1,3-dioxoisoindolin-2-yl)acetamide (8g). Yield 79%; yellow solid;
1
ꢁ
mp 197–198 C; H NMR (400 MHz, DMSO-d6) d 1.10 (t, 6H, 2ꢂ
–CH3); 3.22–3.27 (m, 4H, 2ꢂ –CH2–); 3.36–3.41 (m, 4H, 2ꢂ –CH2–);
4.11 (s, 2H, –CH2–); 6.52 (d, J ¼ 5.5 Hz, 1H, Ar–H); 6.91 (d, J ¼
8.8 Hz, 1H, Ar–H); 6.97 (s, 1H, Ar–H), 7.46–7.50 (m, 2H, Ar–H, NH-
exchangeable with D2O); 7.56 (d, J ¼ 8.6 Hz, 1H, Ar–H); 7.77 (s, 1H,
Ar–H), 8.16 (t, J ¼ 5.2 Hz, 1H, NH-exchangeable with D2O); 8.28 (d,
J ¼ 8.9 Hz, 1H, Ar–H); 8.38 (d, J ¼ 5.6 Hz, 1H, Ar–H); 13C NMR (100
MHz, DMSO-d6) d 12.4, 37.6, 40.8, 42.6, 44.7, 99.0, 105.3, 114.7,
116.2, 117.8, 124.4, 124.6, 125.5, 127.2, 127.7, 134.1, 135.5, 150.7,
151.7, 152.2, 166.6, 167.6, 168.9 HRMS calcd for C25H26ClN5O3 [M
+ H]+ 480.1758 found 480.1743.
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DMSO-d6) d 12.6, 25.4, 27.5, 34.6, 37.7, 39.7, 42.7, 44.7, 99.1, 105.2, 2H, –CH2–); 2.54 (t, J ¼ 4.8 Hz, 4H, 2ꢂ –CH2–); 3.07–3.11 (m, 2H,
114.3, 116.1, 117.8, 124.2, 124.5, 124.7, 125.4, 127.9, 133.7, 135.1, –CH2–); 3.20–3.27 (m, 2H, –CH2–); 3.40 (t, J ¼ 4.7 Hz, 4H, 2ꢂ –CH2–);
149.3, 150.6, 152.4, 168.1, 168.5, 170.7 HRMS calcd for 3.55 (t, J ¼ 6.2 Hz, 2H, –CH2–); 4.10 (s, 2H, –CH2–); 4.48 (s, 1H, –OH);
C28H32ClN5O3 [M + H]+ 522.2227 found 522.2239.
6.47 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.20 (dd, J ¼ 1.6, 8.6 Hz, 1H, Ar–H);
7.30 (d, J ¼ 1.5 Hz, 1H, Ar–H); 7.34 (t, J ¼ 5.5 Hz, 1H, NH-
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-3-(5-(diethylamino)-
1,3-dioxoisoindolin-2-yl)propanamide (8l). Yield 68%; yellow solid; exchangeable with D2O); 7.44 (dd, J ¼ 2.1, 9.0 Hz, 1H, Ar–H); 7.64
mp 142–143 ꢁC; 1H NMR (400 MHz, DMSO-d6) d 1.08 (t, J ¼ 7.3 Hz, (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.75 (d, J ¼ 2.0 Hz, 1H, Ar–H); 8.16 (t, J ¼
6H, 2ꢂ –CH3); 1.35–1.45 (m, 6H, 3ꢂ –CH2–); 1.61–1.66 (m, 2H, 5.5 Hz, 1H, NH-exchangeable with D2O); 8.25 (d, J ¼ 9.0 Hz, 1H, Ar–
–CH2–); 2.37 (t, J ¼ 7.2 Hz, 2H, –CH3); 3.10–3.14 (m, 2H, –CH2–); H); 8.36 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6)
3.24–3.30 (m, 2H, –CH2–); 3.36–3.41 (m, 4H, 2ꢂ –CH2–); 3.68 (t, J ¼ d 26.1, 26.8, 28.1, 29.4, 39.5, 42.9, 47.5, 49.1, 53.5, 59.1, 60.4, 99.0,
7.2 Hz, 2H, –CH3); 6.42 (d, J ¼ 5.2 Hz, 1H, Ar–H); 6.75 (dd, J ¼ 2.2, 108.1, 117.9, 118.1, 119.3, 124.5, 124.8, 125.1, 127.9, 133.7, 134.6,
8.6 Hz, 1H, Ar–H); 6.85 (d, J ¼ 2.4 Hz, 1H, Ar–H), 7.26 (t, J ¼ 5.3 Hz, 149.3, 150.6, 152.1, 155.7, 166.6, 167.7, 168.2 HRMS calcd for
1H, NH-exchangeable with D2O); 7.37 (dd, J ¼ 2.0, 9.0 Hz, 1H, Ar– C31H37ClN6O4 [M + H]+ 593.2598 found 593.2604.
H); 7.47 (d, J ¼ 8.7 Hz, 1H, Ar–H); 7.77 (d, J ¼ 2.2 Hz 1H, Ar–H), 8.06
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-3-(5-(4-(2-hydroxyethyl)
(d, J ¼ 9.0 Hz, 1H, Ar–H); 8.26 (t, J ¼ 5.3 Hz, 1H, NH-exchangeable piperazin-1-yl)-1,3-dioxoisoindolin-2-yl)propanamide (8p). Yield
with D2O); 8.38 (d, J ¼ 5.2 Hz, 1H, Ar–H); 13C NMR (100 MHz, 69%; yellow solid; mp 211–212 C; H NMR (500 MHz, DMSO-d6)
1
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DMSO-d6) d 12.6, 26.4, 26.9, 28.5, 29.8, 34.6, 39.5, 41.1, 42.7, 44.5, d 2.42–2.45 (m, 4H, 2ꢂ –CH2–); 2.53 (t, J ¼ 5.1 Hz, 4H, 2ꢂ –CH2–);
99.1, 105.3, 114.4, 116.1, 117.9, 124.2, 124.6, 124.8, 125.4, 127.8, 3.26–3.31 (m, 4H, 2ꢂ –CH2–); 3.33–3.35 (m, 4H, 2ꢂ –CH2–); 3.52–
133.8, 135.2, 149.4, 150.7, 152.5, 168.1, 168.7, 170.6 HRMS calcd for 3.55 (m, 2H, –CH2–); 3.76 (t, J ¼ 7.1 Hz, 2H, –CH2–); 4.47 (s, 1H, OH);
C30H36ClN5O3 [M + H]+ 550.2540 found 550.2521.
6.49 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.11 (dd, J ¼ 2.3, 8.5 Hz, 1H, Ar–H);
N-(2-((7-Chloroquinolin-4-yl)amino)ethyl)-2-(5-(4-(2-hydroxyethyl) 7.19 (d, J ¼ 2.3 Hz, 1H, Ar–H); 7.28 (t, J ¼ 5.2 Hz, 1H, NH-
piperazin-1-yl)-1,3-dioxoisoindolin-2-yl)acetamide (8m). Yield 75%; exchangeable with D2O); 7.40 (dd, J ¼ 2.2, 9.0 Hz, 1H, Ar–H); 7.53
yellow solid; mp 218–219 ꢁC; 1H NMR (500 MHz, DMSO-d6) d 2.45 (t, (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.77 (d, J ¼ 2.3 Hz, 1H, Ar–H); 8.08 (d, J ¼
J ¼ 6.1 Hz, 2H, –CH2–); 2.54 (t, J ¼ 4.8 Hz, 4H, 2ꢂ –CH2–); 3.11–3.15 8.9 Hz, 1H, Ar–H); 8.25 (t, J ¼ 5.4 Hz, 1H, NH-exchangeable with
(m, 2H, –CH2–); 3.26–3.29 (m, 2H, –CH2–); 3.42 (t, J ¼ 4.5 Hz, 4H, 2ꢂ D2O); 8.39 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6)
–CH2–); 3.53 (t, J ¼ 6.1 Hz, 2H, –CH2–); 4.10 (s, 2H, –CH2–); 4.48 (s, d 34.7, 34.8, 37.7, 42.7, 47.2, 53.2, 59.0, 60.5, 99.0, 107.9, 117.7, 117.8,
1H, –OH); 6.47 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.21 (dd, J ¼ 1.5, 8.6 Hz, 1H, 119.2, 124.2, 124.5, 124.8, 127.9, 133.8, 134.5, 149.4, 150.4, 152.3,
Ar–H); 7.30 (d, J ¼ 1.4 Hz, 1H, Ar–H); 7.35 (t, J ¼ 5.6 Hz, 1H, NH- 153.3, 168.0, 168.4, 170.9. HRMS calcd for C28H31ClN6O4 [M + H]+
exchangeable with D2O); 7.45 (dd, J ¼ 2.1, 9.0 Hz, 1H, Ar–H); 7.66 551.2129 found 551.2141.
(d, J ¼ 8.6 Hz, 1H, Ar–H); 7.78 (d, J ¼ 2.0 Hz, 1H, Ar–H); 8.18 (t, J ¼
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-3-(5-(4-(2-hydroxyethyl)
5.7 Hz, 1H, NH-exchangeable with D2O); 8.29 (d, J ¼ 9.0 Hz, 1H, Ar– piperazin-1-yl)-1,3-dioxoisoindolin-2-yl)propanamide (8q). Yield
H); 8.39 (d, J ¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6) 68%; yellow solid; mp 162–163 C; H NMR (500 MHz, DMSO-d6)
1
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d 38.7, 42.4, 47.5, 49.1, 53.3, 59.1, 60.6, 99.0, 108.1, 117.3, 117.8, d 1.50–1.55 (m, 2H, –CH2–); 1.62–1.68 (m, 2H, –CH2–); 2.41–2.47 (m,
119.4, 124.3, 124.6, 125.1, 127.9, 133.7, 134.7, 149.5, 150.6, 152.2, 4H, 2ꢂ –CH2–); 2.55 (t, J ¼ 5.0 Hz, 4H, 2ꢂ –CH2–); 3.13–3.16 (m, 2H,
155.5, 166.7, 167.8, 168.2 HRMS calcd for C27H29ClN6O4 [M + H]+ –CH2–); 3.27–3.31 (m, 2H, –CH2–); 3.41 (t, J ¼ 4.5 Hz, 4H, 2ꢂ –CH2–);
537.1972 found 537.1961.
3.54 (t, J ¼ 6.1 Hz, 2H, –CH2–); 3.75 (t, J ¼ 7.1 Hz, 2H, –CH2–); 4.48 (s,
N-(4-((7-Chloroquinolin-4-yl)amino)butyl)-2-(5-(4-(2-hydroxyethyl) 1H, OH); 6.47 (d, J ¼ 5.5 Hz, 1H, Ar–H); 7.10 (dd, J ¼ 2.2, 8.6 Hz, 1H,
piperazin-1-yl)-1,3-dioxoisoindolin-2-yl)acetamide (8n). Yield 83%; Ar–H); 7.18 (d, J ¼ 2.2 Hz, 1H, Ar–H); 7.27 (t, J ¼ 5.3 Hz, 1H, NH-
yellow solid; mp 151–152 ꢁC; 1H NMR (500 MHz, DMSO-d6) d 1.50– exchangeable with D2O); 7.41 (dd, J ¼ 2.1, 9.0 Hz, 1H, Ar–H); 7.52
1.55 (m, 2H, –CH2–); 1.62–1.68 (m, 2H, –CH2–); 2.44 (t, J ¼ 6.1 Hz 2H, (d, J ¼ 8.5 Hz, 1H, Ar–H); 7.78 (d, J ¼ 2.2 Hz, 1H, Ar–H); 8.05 (d, J ¼
–CH2–); 2.55 (t, J ¼ 4.9 Hz, 4H, 2ꢂ –CH2–); 3.10–3.14 (m, 2H, –CH2–); 9.0 Hz, 1H, Ar–H); 8.27 (t, J ¼ 5.4 Hz, 1H, NH-exchangeable with
3.25–3.29 (m, 2H, –CH2–); 3.41 (t, J ¼ 4.5 Hz, 4H, 2ꢂ –CH2–); 3.54 (t, J D2O); 8.40 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6)
¼ 6.1 Hz, 2H, –CH2–); 4.11 (s, 2H, –CH2–); 4.49 (s, 1H, –OH); 6.48 (d, J d 25.4, 27.9, 34.6, 37.9, 39.1, 42.7, 47.8, 53.1, 59.1, 60.6, 99.1, 107.8,
¼ 5.5 Hz, 1H, Ar–H); 7.22 (dd, J ¼ 1.5, 8.5 Hz, 1H, Ar–H); 7.31 (d, J ¼ 117.4, 117.9, 119.1, 124.3, 124.5, 124.9, 127.8, 133.9, 134.6, 149.6,
1.4 Hz, 1H, Ar–H); 7.34 (t, J ¼ 5.6 Hz, 1H, NH-exchangeable with 150.3, 152.5, 153.5, 168.1, 168.7, 170.6. HRMS calcd for
D2O); 7.43 (dd, J ¼ 2.2, 9.0 Hz, 1H, Ar–H); 7.65 (d, J ¼ 8.5 Hz, 1H, Ar– C30H35ClN6O4 [M + H]+ 579.2442 found 579.2457.
H); 7.77 (d, J ¼ 2.0 Hz, 1H, Ar–H); 8.19 (t, J ¼ 5.7 Hz, 1H, NH-
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-3-(5-(4-(2-hydroxyethyl)
exchangeable with D2O); 8.27 (d, J ¼ 9.0 Hz, 1H, Ar–H); 8.38 (d, J piperazin-1-yl)-1,3-dioxoisoindolin-2-yl)propanamide (8r). Yield
¼ 5.4 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6) d 25.5, 27.1, 64%; yellow solid; mp 102–103 C; H NMR (500 MHz, DMSO-d6)
1
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38.8, 42.5, 47.3, 49.0, 53.2, 59.0, 60.5, 99.1, 108.2, 117.8, 117.9, 119.4, d 1.32–1.44 (m, 6H, 3ꢂ –CH2–); 1.63–1.68 (m, 2H, –CH2–); 2.42–2.48
124.4, 124.5, 125.0, 127.8, 133.8, 134.7, 149.4, 150.5, 152.2, 155.5, (m, 4H, 2ꢂ –CH2–); 2.54 (t, J ¼ 5.0 Hz, 4H, 2ꢂ –CH2–); 3.11–3.15 (m,
166.6, 167.8, 168.3 HRMS calcd for C29H33ClN6O4 [M + H]+ 565.2285 2H, –CH2–); 3.24–3.30 (m, 2H, –CH2–); 3.43 (t, J ¼ 4.8 Hz, 4H, 2ꢂ
found 565.2268.
–CH2–); 3.57 (t, J ¼ 6.1 Hz, 2H, –CH2–); 3.75 (t, J ¼ 7.1 Hz, 2H, –CH2–
N-(6-((7-Chloroquinolin-4-yl)amino)hexyl)-2-(5-(4-(2-hydroxyethyl) ); 4.47 (s, 1H, OH); 6.45 (d, J ¼ 5.4 Hz, 1H, Ar–H); 7.09 (dd, J ¼ 2.1,
piperazin-1-yl)-1,3-dioxoisoindolin-2-yl)acetamide (8o). Yield 75%; 8.7 Hz, 1H, Ar–H); 7.16 (d, J ¼ 2.1 Hz, 1H, Ar–H); 7.28 (t, J ¼ 5.1 Hz,
yellow solid; mp 118–119 ꢁC; 1H NMR (500 MHz, DMSO-d6) d 1.31– 1H, NH-exchangeable with D2O); 7.40 (dd, J ¼ 2.0, 9.0 Hz, 1H, Ar–H);
1.45 (m, 6H, 3ꢂ –CH2–); 1.62–1.67 (m, 2H, –CH2–); 2.46 (t, J ¼ 6.2 Hz, 7.51 (d, J ¼ 8.4 Hz, 1H, Ar–H); 7.79 (d, J ¼ 2.1 Hz, 1H, Ar–H); 8.07 (d, J
8526 | RSC Adv., 2019, 9, 8515–8528
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¼ 9.0 Hz, 1H, Ar–H); 8.29 (t, J ¼ 5.5 Hz, 1H, NH-exchangeable with values obtained in the compound containing wells by values
D2O); 8.41 (d, J ¼ 5.3 Hz, 1H, Ar–H); 13C NMR (125 MHz, DMSO-d6) obtained for control wells containing cells incubated with
d 26.3, 26.9, 28.4, 29.6, 34.5, 39.7, 42.8, 47.4, 49.3, 53.7, 59.3, 60.6, a dilution series of DMSO and multiplying this value by 100.
99.0, 107.7, 117.5, 117.9, 119.3, 124.4, 124.8, 124.8, 127.9, 133.8, SDS (20%) was included as a positive control. Cytotoxic evalu-
134.7, 149.5, 150.5, 152.8, 153.8, 168.2, 168.9, 170.5. HRMS calcd for ation was completed twice, with each compound tested in
C32H39ClN6O4 [M + H]+ 607.2755 found 607.2769.
duplicate. The IC50 is dened as the lowest concentration of
compound tested at which exactly 50% cell viability was
observed and was calculated using a non-linear regression curve
using Graphpad Prism 5. The SI values were determined as
Materials and methods
Bacterial strains and growth conditions
a function of IC50/MIC99
.
M. tuberculosis mc26230 (ref. 29) was grown at 37 ꢁC in Mid-
dlebrook 7H9 supplemented with oleic-albumin-dextrose-
catalase enrichment (OADC) and 109 mM of pantothenic acid
(complete 7H9).
Conflicts of interest
The authors declare no conict of interest.
Abbreviations
Drug susceptibility testing
The vulnerability of M. tuberculosis mc26230 to the synthesized
compounds was determined as reported previously.30 Briey, an
exponentially growing culture was diluted in complete 7H9 to
and OD600 ¼ 0.01. The bacteria were then seeded in 100 mL
volumes in all the wells of a 96-well plate except the rst column
of wells which contained 200 mL of bacterial suspension.
MIC990
MW
99% minimum inhibitory concentration
microwave
+SAR
NMP
DMF
Structure activity relationship
N-Methyl-2-pyrrolidone
Dimethylformamide
Dimethyl sulfoxide
Compounds (stock concentration 10 mg mLꢀ1) were directly DMSO
SI value
IC50
Selectivity index
50% inhibitory concentration
added to the wells of the rst column so as to achieve
a concentration of 200 mg mLꢀ1 (or 100 mg mLꢀ1 in cases where
precipitation at the higher concentration was observed). Two-
fold serial dilutions were then carried out by transferring 100
mL of bacterial suspension from the rst column of wells to the
second column, mixing, and repeating this procedure for each
consecutive column. The plates were then placed in sealed
plastic bags and incubated at 37 ꢁC. Aer 7 days of incubation,
plates were visually inspected to determine the MIC, which was
dened as the minimal concentration of compound at which no
growth of bacteria was observed. Drug susceptibility testing was
completed twice, with each compound tested in duplicate.
Isoniazid was included as a positive control.
Acknowledgements
Council of Scientic and Industrial Research (CSIR), New Delhi,
India was acknowledged by AR for CSIR-JRF Fellowship (A.R.)
with Ref. No. 09/254(0269)/2017-EMR-1. Science and Engi-
neering Research Board (SERB), New Delhi was acknowledged
by VK for nancial assistance with grant no. EMR/2015/001687.
LK acknowledges the support by the Fondation pour la
´
Recherche Medicale (FRM) (DEQ20150331719) and the Labex
Cytotoxicity assay
EpiGenMed under the program « Investissements d'avenir »
Cell viability was determined using Vero cells (ATCC, Sigma,
Germany) grown in RPMI medium (Gibco, USA), supplemented
with 10% decomplemented fetal calf serum, under a 5% CO2
atmosphere. Cells were seeded in 96-well plates at a density of 2
ꢂ 104 cells per well in 160 mL medium and incubated overnight
at 37 ꢁC to allow cells to adhere. Compounds (dissolved in
DMSO) were freshly diluted to appropriate concentrations in
RPMI, so as to allow addition of 20 mL volumes of the diluted
compounds to the cells that resulted in nal compound
concentrations ranging from 100 mg mLꢀ1 to 0.78 mg mLꢀ1. The
maximum nal concentration of DMSO was 1% (v/v) and no
cytotoxic effect of DMSO was observed at this coꢀn1centration.
(ANR-10-LABX-12-01).
References
1 S. Chetty, M. Ramesh, A. S. Pillay and M. E. S. Soliman,
Bioorg. Med. Chem. Lett., 2017, 27, 370–386.
2 World Health Organization (WHO), Global tuberculosis
report, 2016, available from: http://www.apps.who.int/iris/
bitstream/10665/250441/1/9789241565394-eng.pdf?ua¼1,
2016, accessed 3 October 2017.
3 Revised National Tuberculosis Control Program, Training
manual on intensied TB/HIV package, Ministry of Health
and Family Welfare, New Delhi, 2017.
ꢁ
Aer 24 h incubation at 37 C, 20 mL of 1 mg mL resazurin
(Sigma, Germany) was added to each well and the cells were
incubated for an additional 3 hours at 37 ꢁC. Fluorescence was
measured in a Polarstar Omega uorometer using appropriate
lters (540 nm excitation and 590 nm emission wave length).
Percentage survival was determined by dividing uorescence
4 X. Lu, J. Tang, S. Cui, B. Wan, S. G. Franzblauc, T. Zhang,
X. Zhang and K. Ding, Eur. J. Med. Chem., 2017, 125, 41.
5 WHO Multidrug and extensively drug-resistant TB 2010 Global
report on surveillance and response (http://www.apps.who.int/
iris/bitstream/10665/44286/1/9789241599191_eng.pdf).
This journal is © The Royal Society of Chemistry 2019
RSC Adv., 2019, 9, 8515–8528 | 8527

View Article Online
RSC Advances
Paper
6 H. Janmanchi, A. Raju, M. S. Degani, M. K. Ray and 20 S. G. Stewart, C. J. Braun, S. L. Ng, M. E. Polomska, M. Karimi
M. G. R. Rajan, S. Afr. J. Bot., 2017, 113, 421. and L. J. Abraham, Bioorg. Med. Chem., 2010, 18, 650.
7 A. H. Diacon, A. Pym, M. Grobusch, R. Patientia, 21 S. H. L. Kok, R. Gambari, C. H. Chu, M. C. W. Yuen, E. Lin,
R. Rustomjee, L. Page-Shipp, C. Pistorius, R. Krause,
M. Bogoshi, G. Churchyard, A. Venter, J. Allen,
J. C. Palomino, T. De Marez, R. P. van Heeswijk, N. Lounis,
P. Meyvisch, J. Verbeeck, W. Parys, K. de Beule, K. Andries
and D. F. Mc Neeley, N. Engl. J. Med., 2009, 360, 2397.
8 N. Veziris, M. Ibrahim, N. Lounis, T. Andries and V. Jarlier,
PLoS One, 2011, 6, 17556.
R. S. M. Wong, F. Y. Lau, G. Y. M. Cheng, W. S. Lam,
S. H. Chan, K. H. Lam, C. H. Cheng, P. B. S. Lai,
M. W. Y. Yu, F. Cheung, J. C. O. Tang and A. S. C. Chan,
Bioorg. Med. Chem., 2008, 16, 3626.
22 S. M. Sami, R. T. Dorr, D. S. Alberts, A. M. Solyom and
W. A. Remers, J. Med. Chem., 2000, 43, 3067.
23 R. Dahlbom, B. Karlen, R. George and D. J. Jenden, J. Med.
Chem., 1966, 9, 843–846.
9 J. Cohen, Science, 2013, 339, 130.
10 A. H. Diacon, A. Pym, M. P. Grobusch, J. M. de los Rios, 24 H. Akgun, I. Karamelekoglu, B. Berk, I. Kurnaz, G. Saribiyik,
E. Gotuzzo, I. Vasilyeva, V. Leimane, K. Andries, N. Bakare, S. Oktem and T. Kocagoz, Bioorg. Med. Chem., 2012, 20, 4149.
T. De Marez, M. Haxaire-Theeuwes, N. Lounis, P. Meyvisch, 25 (a) J. L. Santos, P. R. Yamasaki, C. M. Chin, C. H. Takashi,
E. De Paepe, R. P. G. van Heeswijk and B. Dannemann, N.
Engl. J. Med., 2014, 371, 723.
11 S. Umamatheswari and C. Sankar, Bioorg. Med. Chem. Lett.,
2017, 27, 695.
F. R. Pavan and C. Q. F. Leite, Bioorg. Med. Chem., 2009,
17, 3795; (b) A. Kamal, A. HariBabu, A. V. Ramana,
R. Sinha, J. S. Yadava and S. K. Arorab, Bioorg. Med. Chem.
Lett., 2005, 15, 1923.
12 S. Jayaprakash, Y. Iso, B. Wan, S. G. Franzblau and 26 A. Rani, A. Viljoen, Sumanjit, L. Kremer and V. Kumar,
A. P. Kozikowski, ChemMedChem, 2006, 1, 593. ChemistrySelect, 2017, 2, 10782.
13 L. E. Bermudez, P. Kolonoski, M. Wu, P. A. Aralar, 27 (a) A. Singh, A. Viljoen, L. Kremer and V. Kumar, Future Med.
C. B. Inderlied and L. S. Young, Antimicrob. Agents
Chemother., 1999, 43, 1870.
14 L. E. Bermudez, P. Kolonoski, L. E. Seitz, M. Petrofsky,
R. Reynolds and M. Wu, Antimicrob. Agents Chemother.,
2004, 48, 3556.
Chem., 2017, 9, 1701; (b) A. Singh, C. Biot, A. Viljoen,
C. Dupont, L. Kremer, K. Kumar and V. Kumar, Chem. Biol.
Drug Des., 2017, 89, 856; (c) A. Singh, J. Gut, P. J. Rosenthal
and V. Kumar, Eur. J. Med. Chem., 2017, 5, 269; (d)
S. Kumar, A. Saini, J. Gut, P. J. Rosenthal, R. Raj and
V. Kumar, Eur. J. Med. Chem., 2017, 138, 993.
15 L. E. Bermudez, P. Kolonoski, M. Petrofsky, M. Wu,
C. B. Inderlied and L. S. Young, J. Infect. Dis., 2003, 187, 1977. 28 D. Di, F. M. Krogstad, L. D. Byers and D. J. Krogstad, J. Med.
16 J. Mao, H. Yuan, Y. Wang, B. Wan, D. Pak, R. He and
S. G. Franzblau, Bioorg. Med. Chem. Lett., 2010, 20, 1263.
17 J. Mao, Y. Wang, B. Wan, A. P. Kozikowski and
S. G. Franzblau, ChemMedChem, 2007, 2, 1624.
18 U. Sharma, P. Kumar and B. Kumar, Mini-Rev. Med. Chem.,
2010, 10, 678.
Chem., 1998, 41, 4918.
29 V. K. Sambandamurthy, S. C. Derrick, T. Hsu, B. Chen,
M. H. Larsen, K. V. Jalapathy, M. Chen, J. Kim,
S. A. Porcelli, J. Chan, S. L. Morris and W. R. Jacobs Jr,
Vaccine, 2006, 24, 6309.
30 J. Ollinger, M. A. Bailey, G. C. Moraski, A. Casey, S. Florio,
T. Alling, M. J. Miller and T. Parish, PLoS One, 2013, 8,
e60531.
19 S. M. Capitosti, T. P. Hansen and M. L. Brown, Bioorg. Med.
Chem. Lett., 2004, 12, 327.
8528 | RSC Adv., 2019, 9, 8515–8528
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