Variedly connected 1,8-naphthalimide-7-chloroquinoline conjugates: Synthesis, anti-mycobacterial and cytotoxic evaluation

Article abstract of DOI:10.1016/j.bioorg.2019.103241

Recent disclosures about anti-bacterial and anti-tubercular potential of naphthalimide and quinoline core respectively propelled us to synthesize a library of 1,8-naphthalimide-7-chloroquinoline hybrids. Different modes of linkage between two pharmacophoric units viz. simple alkyl chains and induction of amide bond were used and the substituents on the naphthalimide core were varied in order to determine Structure-Activity-Relationship (SAR). Our findings demonstrated that simple alkyl chain linked conjugates showed better activity profiles without any cytotoxicity, while the inclusion of amide bond enhanced the cytotoxic tendency. An interesting behaviour of conjugates in terms of activity and cytotoxicity was observed via switching over the nature of linker between two pharmacophores.

Full text of DOI:10.1016/j.bioorg.2019.103241

Journal Pre-proofs
Variedly connected 1,8-naphthalimide-7-chloroquinoline conjugates: Synthe-
sis, anti-mycobacterial and cytotoxic evaluation
Shalini, Matt D. Johansen, Laurent Kremer, Vipan Kumar
PII:
S0045-2068(19)30688-1
DOI:
https://doi.org/10.1016/j.bioorg.2019.103241
YBIOO 103241
Reference:
To appear in:
Bioorganic Chemistry
Received Date:
Revised Date:
Accepted Date:
30 April 2019
1 August 2019
30 August 2019
Please cite this article as: Shalini, M.D. Johansen, L. Kremer, V. Kumar, Variedly connected 1,8-naphthalimide-7-
chloroquinoline conjugates: Synthesis, anti-mycobacterial and cytotoxic evaluation, Bioorganic Chemistry (2019),
doi: https://doi.org/10.1016/j.bioorg.2019.103241
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Variedly connected 1,8-naphthalimide-7-chloroquinoline conjugates:
Synthesis, anti-mycobacterial and cytotoxic evaluation
a
b
b,c
a
Shalini , Matt D. Johansen , Laurent Kremer , Vipan Kumar*
a
Department of Chemistry, Guru Nanak Dev University, Amritsar-143005, Punjab, India
b
Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS, UMR 9004 Université de
Montpellier, France
c
INSERM, IRIM, 34293 Montpellier, France
Abstract: Recent disclosures about anti-bacterial and anti-tubercular potential of naphthalimide and
quinoline core respectively propelled us to synthesize a library of 1,8-naphthalimide-7-
chloroquinoline hybrids. Different modes of linkage between two pharmacophoric units viz. simple
alkyl chains and induction of amide bond were used and the substituents on the naphthalimide core
were varied in order to determine Structure-Activity-Relationship (SAR). Our findings demonstrated
that simple alkyl chain linked conjugates showed better activity profiles without any cytotoxicity,
while the inclusion of amide bond enhanced the cytotoxic tendency. An interesting behaviour of
conjugates in terms of activity and cytotoxicity was observed via switching over the nature of linker
between two pharmacophores.
Keywords: 1,8-naphthalic anhydride, 7-chloroquinoline, anti-mycobacterial, cytotoxicity, structure-
activity relationship.
1
. Introduction
Mycobacterium tuberculosis (Mtb); the causative agent of Tuberculosis (TB), remains a global health
concern with huge impact particularly in asian and african continents. According to WHO Global
Tuberculosis report 2018, TB has become one of the top 10 causes of death worldwide. Moreover, co-
morbidity with HIV/AIDS has further left the matter a grave concern as there is recorded 1.3 million
deaths among HIV-negative people and additional 0.3 million deaths among HIV-positive people [1].
Recently, clinical prognoses have worsened due to the emergence of multi-drug resistant (MDR) and
extensive-drug resistant (XDR) TB which causes non-compliance among TB patients with
conventional drug regimens [1]. Multiple factors such as long treatment duration, increased toxicity,
cost of treatment of MDR TB have made the fight against this epidemic more arduous than ever. In
order to overcome the multitude of continuously arising challenges in the fight against TB, there is
particular interest in the Research and Development sector where new compounds can be introduced
with better efficacy and less severe side effects [2].
1

Quinoline is a privileged entity which acts as a pharmacophore in various drugs owing to its
antimalarial, anticancer, antimicrobial, antifungal, antitubercular, antileishmanial properties [3]. There
are some anti-TB drugs which already have been commercialized viz ciprofloxacin, ofloxacin,
levofloxacin, all of which contain quinoline core [4]. Besides, the success in its exploration is evident
from bedaquiline; a diaryl quinoline based scaffold that has been approved by United States Food and
Drug Administration (FDA) and European Medicine Agency (EMA) and is one of only two anti-TB
drugs successfully developed in the last 50 years. This drug is under advance phase of clinical trial
and some countries have already started its usage as a regimen for MDR-TB [5]. However, clinical
applications have been restricted by a black box warning due to serious adverse effects, such as
increased mortality and QT (electrical depolarization and repolarization of the ventricles)
prolongation [6]. In the endeavour to explore the potential of quinoline, researchers are being
motivated to design and produce new molecules with improved safety and pharmacological profiles
which can overcome these persisting limitations. There are a number of reports showing quinoline
based derivatives and molecular hybrids having significant anti-mycobacterial potency, among which
quinoline diamines proved to be a considerable precursor to produce a novel anti-TB entity [7]. The
diamine core also finds its importance from Ethambutol, one of the first line drugs to treat TB, Figure
1
.
Heterocyclic naphthalimides have emerged as useful molecular framework because of its extensive
potentiality in medicinal applications. Few reports have displayed naphthalimides as anticancer,
antibacterial, antifungal, antiviral, anti-inflammatory, antidepressant agents [8]. The -deficient
conjugated planar structure that enables naphthalimide derivatives to feasibly interact with various
biological cations, anions, small molecules and macromolecules like DNA, enzymes & receptors via
non-covalent bonds, eventually allows us to exploit these properties in current medicinal research [9].
Currently, naphthalimide based drugs viz. Amonafide and Mitonafide, are under clinical trials for their
anticancer potential while Pinafide and Mitonafide have been recognized for their promising anti-TB
activities [10], Figure 1.
The nature of linker has great influence on the pharmacokinetic behaviour of the drug while designing
a hybrid compound [11]. Using this concept, 7-chloroquinoline and 1,8-naphthalic anhydride, chosen
as pharmacophoric units were connected through simple alkyl chains (using diamines) and via
introducing amide bond. Thus, in the pursuit of our efforts to develop new hybrid compounds with
biological potential [12], we herein report the synthesis, anti-mycobacterial and cytotoxic evaluation
of 4-substituted 1,8-naphthalimide-7-chloroquinoline conjugates connected through varied linkers in
order to study their structure-activity relationship.
2

2
. Results and Discussion
2
.1 Chemistry
In the synthesis of the first set of target compounds, with alkyl chains as linker between two
pharmacophoric units, 1,8-naphthalic anhydride 1 was heated with quinoline diamine 2, prepared
°
from reported methodology [13], at 150 C using anhydrous N-methyl-2-pyrrolidone (NMP) as
solvent. The compounds containing bromo substituted naphthalimide were further used as precursors
to synthesize other target molecules. The synthesis of 4 was done by heating 3 with a secondary
°
amine (piperidine/morpholine/hydroxyethyl piperazine) at 180 C keeping NMP as solvent, Scheme 1.
The structures of the synthesized hybrids were assigned on the basis of spectral data and analytical
+
evidences. For illustration, the compound 3a, showed molecular ion peak at m/z 402.0945 [M+1] in
1
its HRMS. Its H NMR spectrum showed doublets at  6.63 (J=5.1 Hz) and 8.11 (J=8.9 Hz)
corresponding to quinoline ring protons and requisite peaks of naphthalimide core as well.
1
3
Appearance of absorption peak at  164.15 in C NMR spectrum of 3a representing carbonyl carbon
further corroborated the assigned structure.
Another set of target compounds with an amide functionality as a linker, was synthesized by initially
heating 1,8-naphthalic anhydride 1 with glycine 5 in the presence of triethyl amine as base and
anhydrous N,N-Dimethylformamide (DMF) as solvent. The product obtained 6 was further reacted
with quinoline-diamines 2 in the presence of 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide
(EDC), N-hydroxybenzotriazole (HOBt) and N,N-Diisopropylethylamine (DIEA) using anhydrous
DMF as solvent to yield 7. Heating of 7 in the presence of secondary amine
°
(
piperidine/morpholine/hydroxyethyl piperazine) at 180 C using NMP as solvent afforded the amide-
linked 4-aminoquinoline-naphthalimides 8 as depicted in Scheme 2. The structures of the synthesized
hybrids were assigned again on the basis of spectral data and analytical evidences. Taking an example
+
of compound 7b, which showed molecular ion peak at m/z 473.1328 [M+1] in its HRMS while the
1
13
1
appearance of desired peaks in H and C NMR spectrum further confirmed the structure. Its H
NMR spectrum showed doublets at  6.55 (J=5.4 Hz), 7.78 (J=1.7 Hz) and 8.12 (J=9.0 Hz)
corresponding to quinoline ring along with another pair of doublets at  8.25 (J=7.8 Hz) and 8.34
(J=7.8 Hz) representing naphthalimide ring protons. Appearance of peaks at  163.27 and 163.32
1
3
representing carbonyl carbons in C NMR spectrum further confirmed the structure.
2
.2 In-vitro anti-mycobacterial and cytotoxic evaluation:
Both the series of synthesized compounds were evaluated for anti-mycobacterial and cytotoxic
2
evaluation against mc 6230 and Vero kidney cell lines, respectively. Among the series where the
pharmacophores were connected via alkyl linkage (3a-j and 4a-o), the MIC value ranges from 6.25-
9
9
3

2
00 g/mL, with most of the compounds proven to be active against Mtb. For contemplation of
Structure-Activity-Relationship (SAR) among the synthesized series, spacer lengths and substituents
on the naphthalimide core were varied. For the hybrids having unsubstituted naphthalimide core 3a-e,
activity increases on increasing the spacer length with 3d (n=6) and 3e (n=8) being the most active
with MIC99 of 12.5 g/mL. Similar trend in activity was observed on introducing the bromo
substituent at C-4 position of naphthalimide core among conjugates 3f-j with the most potent hybrid,
3
i, having hexyl spacer showing MIC99 12.5 g/mL. On replacing bromo with piperidine, an
enhancement in the anti-mycobacterial activity was observed with 4b (n=3) and 4c (n=4), 4d (n=6)
being the potent hybrids with MIC values 12.5 and 6.25 g/mL respectively. The replacement of
9
9
bromo with morpholine and/or hydroxyethyl piperazine did not produce significant changes in the
activity profiles. The conjugates with longer chain length viz. 4i, 4n (n=6) and 4j, 4o (n=8) showed
MIC99 12.5 g/mL. The evaluation of the conjugates for their cytotoxicity assay demonstrated a
general trend among the whole series. Irrespective of the substituents on the naphthalimide core, the
scaffolds with longer chain lengths i.e. with hexyl and octyl spacers showed IC values >100 g/mL
5
0
(except 4n), proving their non-cytotoxicity as evident from 3d, 3e, 3i, 3j, 4d, 4e, 4i, 4j, and 4o. On
analysing the second series of hybrids, where the pharmacophores were connected via induction of an
amide bond along with variable chain lengths as well as substituents, loss of anti-TB activity was
observed with MIC99 values ranges from 12.5-200 g/mL. For hybrids with unsubstituted
naphthalimides viz. 7a-e, the one with butyl spacer, 7c, showed good activity with MIC 12.5 g/mL.
9
9
The introduction of bromo substituent further decreased the anti-mycobacterial activities, irrespective
of the length of alkyl chain as evident from 7g (n=3) and 7j (n=8) with MIC of >200 g/mL. The
9
9
replacement of bromo with a secondary amine viz. piperidine enhanced the activity profiles with all
the corresponding conjugates except 8e exhibiting MIC99 of 12.5 g/mL. On the other hand,
morpholine and/or hydroxyethyl piperazine substituted conjugates did not show any significant anti-
tubercular activities as evident from the hybrids 8f-8o. For cytotoxicity assay, most of compounds of
the synthesized series, except 7j, 8e and 8j, displayed significant IC values, clearly proving their
5
0
cytotoxic tendency. Selectivity Index (SI) of all the synthesized hybrids were also calculated as a
function of the IC /MIC and was observed to be of moderate to good values, Table-1.
5
0
On comparing the observed anti-mycobacterial profiles of both the series of 1,8-naphthalimide-7-
chloroquinoline conjugates, the hybrids having alkyl chain as spacer proved to be active and non-
cytotoxic while the induction of amide linkage not only reduced the anti-mycobacterial efficacy, but
also resulted in increase in cytotoxicity. The most potent of the synthesized hybrids, 4d with hexyl
chain length and piperidine substituent on the naphthalimide core, proved to be the most potent and
non-cytotoxic with MIC of 6.25 g/mL and selectivity index of >16. The SAR of the synthesized
9
9
compounds has been diagrammatically represented in Figure 2.
4

3
. Experimental section
3
.1 General information
Stuart Digital Melting Point apparatus (SMP10) and an open capillary was used to determine melting
1
points and are uncorrected. H NMR spectra were recorded in DMSO-d6 and CDCl with a BRUKER
3
AVANCE II (500 MHz) and JEOL (400 MHz) spectrometer. 13C NMR spectra were recorded in
DMSO-d6 and CDCl with a BRUKER AVANCE II (125 MHz) and JEOL (100 MHz). Chemical
3
shift values are expressed as parts per million (ppm) downfield from TMS (used as reference) and the
coupling constants represented by J values are in hertz. Splitting patterns are indicated as s: singlet, d:
doublet, t: triplet, m: multiplet, dd: double doublet, dt: doublet of a triplet and br: broad peak. Mass
spectra were recorded on a BRUKER high resolution mass spectrometer (micrOTOF-QII).
3
.2 Procedure for synthesis of conjugates 3a-j:
To a well stirred solution of 1,8-naphthalic anhydride 1 (1 mmol) in anhydrous NMP as solvent, was
°
added quinoline diamine 2 (1 mmol) and the reaction mixture was heated at 150 C for 2h. On reaction
completion, as evident from TLC, ice cold water was added to the reaction mixture. The desired
product 3, got precipitated out which was then filtered, dried and recrystallized in ethanol.
3
.2.1 2-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (3a)
°
1
Yield-86%, pale yellow solid, M.P=130-135 C, H NMR (DMSO-d , 500 MHz): δ 3.61-3.65 (m, 2H,
6
2
4
CH ), 4.30 (t, J= 6.8 Hz, 2H, CH ), 6.83 (d, J= 5.1 Hz, 1H, H ), 7.41 (dd, J= 1.4, 8.8 Hz, 1H, H ),
2
2
5
7
10
7
8
.70 (t, J= 5.6 Hz, 1H, NH-exchangeable with D O), 7.78 (s, 1H, H ), 7.83-7.86 (m, 2H, H +H ),
2
3
1
6
8
9
11 13
.11 (d, J= 8.9 Hz, 1H, H ), 8.42-8.53 (m, 5H, H +H +H +H +H ). C NMR (DMSO-d , 125 MHz):
6
δ 164.15, 152.87, 145.45, 143.10, 136.45, 134.79, 131.71, 131.14, 127.63, 127.50, 125.95, 125.15,
+
1
4
22.85, 122.45, 117.50, 99.17, 40.85, 38.22. HRMS calcd for C H ClN O [M+1] 402.0931, found
2
3
16
3
2
02.1024.
3
.2.2
2-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione
(3b)
°
1
Yield-90%, pale yellow solid, M.P=165-170 C, H NMR (DMSO-d , 400 MHz): δ 2.00-2.07 (m, 2H,
6
2
CH ), 3.42-3.46 (m, 2H, CH ), 4.13 (t, J= 6.8 Hz, 2H, CH ), 6.57 (d, J= 6.1 Hz, 1H, H ), 7.41 (d, J=
2
2
2
4
5
7
10
2
.1, 9.0 Hz, 1H, H ), 7.74-7.78 (m, 3H, H +H +H ), 8.17 (s, 1H, NH-exchangeable with D O), 8.24
2
3
1
6
8
9
11 13
(
d, J= 9.1 Hz, 1H, H ), 8.34-8.36 (m, 5H, H +H +H +H +H ). C NMR (DMSO-d , 100 MHz): δ
6
1
64.03, 152.63, 148.57, 145.06, 135.89, 134.75, 131.70, 131.15, 127.80, 127.64, 125.58, 125.06,
+
1
24.38, 122.50, 117.04, 99.16, 41.30, 38.34, 26.83. HRMS calcd for C H ClN O [M+1] 416.1088,
2
4
18
3
2
found 416.1183.
5

3
.2.3 2-(4-((7-chloroquinolin-4-yl)amino)butyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (3c)
°
1
Yield-89%, grey solid, M.P=130-135 C, H NMR (DMSO-d , 500 MHz): δ 1.74-1.78 (m, 4H,
6
2
(
CH ) ), 3.45-3.46 (m, 2H, CH ), 4.08 (t, J= 5.0 Hz, 2H, CH ), 6.68 (d, J= 6.45 Hz, 1H, H ), 7.53 (dd,
2
2
2
2
4
7
10
5
J= 1.8, 8.9 Hz, 1H, H ), 7.78-7.81 (m, 2H, H +H ), 7.87 (d, J=1.6 Hz, 1H, H ), 8.37-8.40 (m, 5H,
H +H +H +H +H ), 8.44 (d, J= 9.1 Hz, 1H, H ), 8.76 (s, 1H, NH-exchangeable with D O). 13C
1
6
8
9
11
3
2
NMR (DMSO-d , 125 MHz): δ 163.87, 153.78, 146.25, 142.56, 136.62, 134.72, 131.61, 131.10,
6
1
27.65, 127.57, 126.07, 125.54, 122.33, 122.30, 116.47, 98.95, 43.07, 25.65, 25.62. HRMS calcd for
+
C H ClN O [M+1] 430.1244, found 430.1337.
2
5
20
3
2
3
.2.4 2-(6-((7-chloroquinolin-4-yl)amino)hexyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (3d)
°
1
Yield-88%, light brown solid, M.P=185-190 C, H NMR (DMSO-d , 500 MHz): δ 1.38-1.44 (m, 4H,
6
(
CH ) ), 1.63-1.69 (m, 4H, (CH ) ), 3.41-3.45 (m, 2H, CH ), 3.99-4.04 (m, 2H, CH ), 6.73 (d, J= 6.75
2 2 2 2 2 2
2
4
7
10
Hz, 1H, H ), 7.63 (dd, J= 1.7, 8.9 Hz, 1H, H ), 7.81-7.85 (m, 2H, H +H ), 7.95 (d, J= 1.6 Hz, 1H,
5
1
6
8
9
11
3
H ), 8.39-8.45 (m, 5H, H +H +H +H +H ), 8.53 (d, J= 9.0 Hz, 1H, H ), 9.02 (s, 1H, NH-
1
3
exchangeable with D O). C NMR (DMSO-d , 125 MHz): δ 163.80, 154.53, 145.15, 141.30, 137.26,
2
6
1
2
34.73, 131.69, 131.11, 127.73, 127.63, 126.50, 125.83, 122.42, 121.31, 116.29, 98.97, 43.41, 27.91,
+
7.87, 26.71, 26.59. HRMS calcd for C H ClN O [M+1] 458.1557, found 458.1655.
2
7
24
3
2
3
.2.5 2-(8-((7-chloroquinolin-4-yl)amino)octyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (3e)
°
1
Yield-88%, grey solid, M.P=105-110 C, H NMR (DMSO-d , 500 MHz): δ 1.31 (s, 8H, (CH ) ),
6
2 4
1
1
.61-1.62 (m, 4H, (CH ) ), 3.21-3.22 (m, 2H, CH ), 4.00 (t, J= 7.2 Hz, 2H, CH ), 6.42 (d, J= 5.4 Hz,
2 2 2 2
2
4
H, H ), 7.34 (s, 1H, NH- exchangeable with D O), 7.41 (dd, J= 1.7, 8.8 Hz, 1H, H ), 7.75 (s, 1H,
2
5
7
10
3
1
H ), 7.80-7.83 (m, 2H, H +H ), 8.26 (d, J= 9.0 Hz, 1H, H ), 8.36 (d, J= 5.1 Hz, 1H, H ), 8.39-8.45
6
8
9
11 13
(
m, 4H, H +H +H +H ). C NMR (DMSO-d , 125 MHz): δ 163.77, 151.90, 150.75, 149.03, 134.68,
6
1
2
33.97, 131.70, 131.11, 127.74, 127.60, 127.50, 124.61, 124.48, 122.44, 117.79, 99.00, 42.90, 29.17,
+
9.15, 28.19, 27.89, 27.05, 26.94. HRMS calcd for C H ClN O [M+1] 486.1870, found 486.1961.
2
9
28
3
2
3
.2.6
6-bromo-2-(2-((7-chloroquinolin-4-yl)amino)ethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione
(
3f)
Yield-84%, pale yellow solid, M.P=240-245 C, H NMR (DMSO-d , 400 MHz): δ 3.56-3.58 (m, 2H,
°
1
6
2
4
CH ), 4.20 (t, J=6.5 Hz, 2H, CH ), 6.62 (d, J= 6.4 Hz, 1H, H ), 7.56 (dd, J= 1.9, 9.0 Hz, 1H, H ), 7.89
2
2
5
9
7
(
d, J=1.8 Hz, 1H, H ), 7.92 (dd, J= 8.0, 7.9 Hz, 1H, H ), 8.12 (d, J=7.6 Hz, 1H, H ), 8.25 (d, J=7.5
6
1
3
8
10
Hz, 1H, H ), 8.40 (d, J=6.3 Hz, 1H, H ), 8.45-8.50 (m, 3H, H +H +H ), 8.65 (s, 1H, NH-
1
3
exchangeable with D O). C NMR (DMSO-d , 100 MHz): δ 163.20, 163.15, 153.10, 146.40, 137.10,
2
6
1
33.10, 132.45, 132.10, 131.45, 131.20, 130.15, 129.24, 128.98, 128.65, 125.90, 125.35, 123.50,
6

+
1
22.03, 121.70, 116.23, 98.90, 40.75, 38.20. HRMS calcd for C H BrClN O [M+1] 480.0036,
23 15 3 2
+
found 480.0136 and [M+3] 482.0036, found 482.0146.
3
.2.7 6-bromo-2-(3-((7-chloroquinolin-4-yl)amino)propyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione
(3g)
°
1
Yield-83%, peach white solid, M.P=115-120 C, H NMR (DMSO-d , 400 MHz): δ 1.98-2.01 (m, 2H,
6
2
CH ), 3.40-3.43 (m, 2H, CH ), 4.10 (t, J=6.7 Hz, 2H, CH ), 6.61 (d, J= 6.5 Hz, 1H, H ), 7.55 (dd, J=
2
2
2
4
5
9
2
1
.0, 9.1 Hz, 1H, H ), 7.88 (d, J=1.9 Hz, 1H, H ), 7.91 (dd, J= 7.8, 8.0 Hz, 1H, H ), 8.11 (d, J=7.5 Hz,
7
6
1
3
8
10
H, H ), 8.24 (d, J=7.4 Hz, 1H, H ), 8.41 (d, J=6.4 Hz, 1H, H ), 8.44-8.49 (m, 3H, H +H +H ), 8.64
1
3
(
s, 1H, NH-exchangeable with D O). C NMR (DMSO-d , 100 MHz): δ 163.96, 163.90, 152.45,
2
6
1
1
45.10, 136.65, 133.31, 132.35, 132.01, 131.10, 131.35, 130.10, 129.15, 128.10, 127.98, 125.92,
25.45, 123.40, 122.15, 121.68, 115.85, 99.10, 40.92, 38.30, 25.99. HRMS calcd for C H BrClN O
2
4
17
3
2
+
+
[
M+1] 494.0193, found 494.0343 and [M+3] 496.0193, found 496.0353.
3
.2.8
6-bromo-2-(4-((7-chloroquinolin-4-yl)amino)butyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione
(3h)
°
1
Yield-85%, Off-white solid, M.P=240-245 C, H NMR (DMSO-d , 400 MHz): δ 1.70-1.75 (m, 4H,
6
2
(
CH ) ), 3.41-3.43 (m, 2H, CH ), 4.05 (t, J=6.5 Hz, 2H, CH ), 6.67 (d, J= 6.5 Hz, 1H, H ), 7.60 (dd,
2
2
2
2
4
5
9
J= 1.8, 9.0 Hz, 1H, H ), 7.89 (d, J=1.9 Hz, 1H, H ), 7.95 (dd, J= 8.0, 8.1 Hz, 1H, H ), 8.17 (d, J=7.6
7
6
1
3
8
10
Hz, 1H, H ), 8.27 (d, J=7.5 Hz, 1H, H ), 8.40 (d, J=6.4 Hz, 1H, H ), 8.45-8.50 (m, 3H, H +H +H ),
1
3
8
1
1
.68 (s, 1H, NH- exchangeable with D O). C NMR (DMSO-d , 100 MHz): δ 163.21, 163.10,
2 6
53.59, 146.26, 135.71, 133.20, 132.12, 131.42, 131.25, 131.10, 130.10, 129.72, 129.15, 127.74,
25.98, 125.62, 122.63, 121.65, 121.36, 116.42, 99.05, 43.06, 25.89, 25.21. HRMS calcd for
+
+
C H BrClN O [M+1] 508.0349, found 508.0459 and [M+3] 510.0349, found 510.0449.
2
5
19
3
2
3
.2.9 6-bromo-2-(6-((7-chloroquinolin-4-yl)amino)hexyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione
3i)
Yield-84%, Off-white solid, M.P=220-225 C, H NMR (DMSO-d , 500 MHz): δ 1.41-1.45 (m, 4H,
(
°
1
6
(
CH ) ), 1.64-1.70 (m, 4H, (CH ) ), 3.39-3.43 (m, 2H, CH ), 4.02 (t, J=7.3 Hz, 2H, CH ), 6.69 (d, J=
2 2 2 2 2 2
2
4
5
6
.45 Hz, 1H, H ), 7.60 (dd, J= 1.7, 9.1 Hz, 1H, H ), 7.90 (d, J=1.8 Hz, 1H, H ), 7.96 (dd, J= 7.9, 7.9
9
7
6
1
Hz, 1H, H ), 8.18 (d, J=7.8 Hz, 1H, H ), 8.28 (d, J=7.8 Hz, 1H, H ), 8.44 (d, J=6.2 Hz, 1H, H ), 8.46-
3
8
10
13
8
.52 (m, 3H, H +H +H ), 8.69 (s, 1H, NH-exchangeable with D O). C NMR (DMSO-d , 125
2 6
MHz): δ 163.32, 163.27, 153.86, 146.44, 136.68, 133.04, 131.99, 131.80, 131.39, 131.13, 130.25,
1
29.55, 129.24, 128.74, 126.16, 125.57, 123.20, 122.46, 122.43, 116.57, 99.01, 43.33, 27.94, 27.80,
7

+
+
2
5
6.70, 26.62. HRMS calcd for C H BrClN O [M+1] 536.0662, found 536.0802 and [M+3]
27 23 3 2
38.0662, found 538.0782.
3
.2.10 6-bromo-2-(8-((7-chloroquinolin-4-yl)amino)octyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione
(3j)
°
1
Yield-83%, light brown solid, M.P=100-105 C, H NMR (DMSO-d , 500 MHz): δ 1.33 (s, 8H,
6
(
CH ) ), 1.62-1.66 (m, 4H, (CH ) ), 3.39-3.40 (m, 2H, CH ), 3.99 (t, J=7.0 Hz, 2H, CH ), 6.69 (d, J=
2 4 2 2 2 2
2
4
5
9
6
.4 Hz, 1H, H ), 7.60 (d, J= 8.9 Hz, 1H, H ), 7.90 (s, 1H, H ), 7.96 (dd, J= 8.0, 7.6 Hz, 1H, H ), 8.17
7
6
1
3
8
10
(
d, J=7.8 Hz, 1H, H ), 8.28 (d, J=7.8 Hz, 1H, H ), 8.44-8.52 (m, 4H, H +H +H +H ), 8.67 (s, 1H,
1
3
NH-exchangeable with D O). C NMR (DMSO-d , 125 MHz): δ 163.29, 163.24, 153.85, 146.48,
2
6
1
1
36.67, 133.02, 131.99, 131.80, 131.39, 131.13, 130.25, 129.54, 129.23, 128.73, 127.64, 126.14,
25.58, 123.19, 122.42, 116.58, 98.98, 43.37, 40.23, 29.10, 29.05, 28.07, 27.81, 26.89, 26.85. HRMS
+
+
calcd for C H BrClN O [M+1] 564.0975, found 564.1075 and [M+3] 566.0975, found 566.1075.
2
9
27
3
2
3
.3 Procedure for synthesis of conjugates 4a-o:
To a well stirred solution of 3 (for 3f-j, when R=Br) (1 mmol) in anhydrous NMP (1-2 mL), was
added different secondary amines (2 mmol) (piperidine/morpholine/hydroxyethyl piperazine) and the
°
reaction mixture was heated at 180 C for 1h. On completion of the reaction, as monitored from TLC,
ice cold water was added to the reaction mixture. The solid got precipitated out of the reaction
mixture which was then filtered, washed with water and recrystallized in ethanol to afford the desired
compounds 4a-o.
3
1
.3.1
2-(2-((7-chloroquinolin-4-yl)amino)ethyl)-6-(piperidin-1-yl)-1H-benzo[de]isoquinoline-
,3(2H)-dione (4a)
°
1
Yield-78%, green solid, M.P>250 C, H NMR (CDCl , 400 MHz): δ 1.62-1.70 (m, 2H, CH -CH -
3
2
2
CH ), 1.78-1.88 (m, 4H, CH -CH -CH ), 3.15-3.18 (m, 4H, CH -CH -CH ), 3.58-3.60 (m, 2H, CH ),
2
2
2
2
2
2
2
2
2
4
7
7
.40 (t, J=7.1 Hz, 2H, CH ), 5.90 (s, 1H, NH-exchangeable with D O), 6.30 (d, J=5.3 Hz, 1H, H ),
2
2
7
4
9
.05 (d, J=8.0 Hz, 1H, H ), 7.21 (dd, J=1.8, 8.8 Hz, 1H, H ), 7.58 (dd, J=7.8, 8.1 Hz, 1H, H ), 7.80-
3
5
6
1
.84 (m, 2H, H +H ), 8.30 (d, J=8.1 Hz, 1H, H ), 8.35 (d, J=5.1 Hz, 1H, H ), 8.40 (d, J=8.0 Hz, 1H,
1
0
8
13
H ), 8.45 (d, J=7.6 Hz, 1H, H ). C NMR (CDCl , 100 MHz): δ 165.01, 164.79, 158.19, 150.70,
3
1
1
50.54, 135.36, 132.91, 131.33, 131.23, 130.85, 129.88, 127.52, 126.33, 125.56, 125.35, 122.80,
21.76, 117.10, 115.32, 114.72, 98.65, 54.45, 40.62, 38.16, 26.30, 24.27. HRMS calcd for
+
C H ClN O [M+1] 485.1666, found 485.1756.
2
8
25
4
2
8

3
1
.3.2
2-(3-((7-chloroquinolin-4-yl)amino)propyl)-6-(piperidin-1-yl)-1H-benzo[de]isoquinoline-
,3(2H)-dione (4b)
°
1
Yield-76%, pale yellow solid, M.P=190-195 C, H NMR (CDCl , 500 MHz): δ 1.70-1.73 (m, 2H,
3
CH -CH -CH ), 1.85-1.91 (m, 4H, CH -CH -CH ), 2.11-2.17 (m, 2H, CH ), 3.23-3.25 (m, 4H, CH -
2
2
2
2
2
2
2
2
CH -CH ), 3.35-3.40 (m, 2H, CH ), 4.32 (t, J=7.7 Hz, 2H, CH ), 6.35 (s, 1H, NH- exchangeable with
2
2
2
2
2
7
4
D O), 6.40 (d, J=6.7 Hz, 1H, H ), 7.16 (d, J=10.0 Hz, 1H, H ), 7.37 (dd, J=2.7, 11.1 Hz, 1H, H ), 7.68
2
9
5
3
(
dd, J=9.1, 10.5 Hz, 1H, H ), 7.90 (d, J=2.6 Hz, 1H, H ), 7.97 (d, J=11.2 Hz, 1H, H ), 8.39 (d, J=10.5
6
1
10
8
13
Hz, 1H, H ), 8.47 (d, J=6.8 Hz, 1H, H ), 8.51 (d, J=10.1 Hz, 1H, H ), 8.59 (d, J=9.1 Hz, 1H, H ). C
NMR (CDCl , 125 MHz): δ 165.28, 164.79, 157.90, 151.98, 149.92, 134.87, 133.29, 131.53, 131.27,
3
1
3
30.11, 128.52, 127.17, 126.25, 125.49, 125.34, 122.73, 121.76, 117.56, 115.24, 114.82, 98.67, 54.64,
+
9.71, 37.39, 26.64, 26.27, 24.40. HRMS calcd for C H ClN O [M+1] 499.1823, found 499.1840.
2
9
27
4
2
3
1
.3.3
2-(4-((7-chloroquinolin-4-yl)amino)butyl)-6-(piperidin-1-yl)-1H-benzo[de]isoquinoline-
,3(2H)-dione (4c)
°
1
Yield-77%, pale yellow solid, M.P=125-130 C, H NMR (CDCl , 500 MHz): δ 1.65-1.68 (m, 2H,
3
CH -CH -CH ), 1.78-1.87 (m, 8H, CH -CH -CH + (CH ) ), 3.16-3.18 (m, 4H, CH -CH -CH ), 3.37-
2
2
2
2
2
2
2 2
2
2
2
3
.40 (m, 2H, CH ), 4.20 (t, J=7.0 Hz, 2H, CH ), 5.91 (s, 1H, NH-exchangeable with D O), 6.33 (d,
2 2 2
2
7
4
J=5.5 Hz, 1H, H ), 7.10 (d, J=8.1 Hz, 1H, H ), 7.25 (dd, J=1.9, 8.9 Hz, 1H, H ), 7.61 (dd, J=7.5, 8.1
9
3
5
6
1
Hz, 1H, H ), 7.83-7.85 (m, 2H, H +H ), 8.32 (d, J=8.3 Hz, 1H, H ), 8.37 (d, J=5.5 Hz, 1H, H ), 8.42
1
0
8
13
(
d, J=8.1 Hz, 1H, H ), 8.49 (d, J=7.1 Hz, 1H, H ). C NMR (CDCl , 125 MHz): δ 164.83, 164.34,
3
1
1
2
57.61, 150.72, 150.54, 135.29, 132.90, 131.38, 131.19, 130.95, 129.96, 127.47, 126.21, 125.42,
25.38, 122.86, 121.81, 117.03, 115.48, 114.74, 98.80, 54.55, 42.94, 39.36, 26.21, 25.80, 25.35,
+
4.33. HRMS calcd for C H ClN O [M+1] 513.1979, found 513.1991.
3
0
29
4
2
3
1
.3.4
2-(6-((7-chloroquinolin-4-yl)amino)hexyl)-6-(piperidin-1-yl)-1H-benzo[de]isoquinoline-
,3(2H)-dione (4d)
°
1
Yield-76%, light brown solid, M.P=105-110 C, H NMR (CDCl , 400 MHz): δ 1.40-1.44 (m, 4H,
3
(CH ) ), 1.65-1.67 (m, 6H, CH -CH -CH + (CH ) ), 1.85-1.90 (m, 4H, CH -CH -CH ), 3.23-3.25
2 2 2 2 2 2 2 2 2 2
(
m, 4H, CH -CH -CH ), 3.30-3.32 (m, 2H, CH ), 4.10 (t, J=7.4 Hz, 2H, CH ), 4.48 (s, 1H, NH-
2
2
2
2
2
2
7
exchangeable with D O), 6.38 (d, J=5.2 Hz, 1H, H ), 7.12 (d, J=8.0 Hz, 1H, H ), 7.31 (dd, J=1.9, 8.9
2
4
3
9
5
6
Hz, 1H, H ), 7.61-7.68 (m, 2H, H +H ), 7.90 (d, J=1.8 Hz, 1H, H ), 8.46 (d, J=8.2 Hz, 1H, H ), 8.49
1
0
1
8
13
(
d, J=8.1 Hz, 1H, H ), 8.52 (d, J=5.1 Hz, 1H, H ), 8.56 (d, J=7.0 Hz, 1H, H ). C NMR (CDCl , 100
3
MHz): δ 164.75, 164.10, 157.30, 152.15, 134.76, 132.52, 131.10, 130.90, 130.50, 129.90, 128.65,
1
26.93, 126.81, 125.42, 125.30, 123.15, 120.56, 117.25, 115.85, 114.69, 99.10, 54.60, 43.35, 40.65,
9

+
2
5
7.92, 27.76, 26.70, 26.50, 26.25, 24.50. HRMS calcd for C H ClN O [M+1] 541.2292, found
32 33 4 2
41.2235.
3
1
.3.5
2-(8-((7-chloroquinolin-4-yl)amino)octyl)-6-(piperidin-1-yl)-1H-benzo[de]isoquinoline-
,3(2H)-dione (4e)
°
1
Yield-75%, dark green solid, M.P=95-100 C, H NMR (CDCl , 500 MHz): δ 1.44-1.48 (m, 8H,
3
(
CH ) ), 1.74-1.79 (m, 6H, CH -CH -CH + (CH ) ), 1.89-1.91 (m, 4H, CH -CH -CH ), 3.24 (s, 4H,
2 4 2 2 2 2 2 2 2 2
CH -CH -CH ), 3.30-3.34 (m, 2H, CH ), 4.18 (t, J=7.5 Hz, 2H, CH ), 5.07 (s, 1H, NH- exchangeable
2
2
2
2
2
2
7
4
with D O), 6.43 (d, J=5.3 Hz, 1H, H ), 7.18 (d, J=8.1 Hz, 1H, H ), 7.36 (dd, J=2.0, 8.8 Hz, 1H, H ),
2
3
9
5
6
7
.67-7.71 (m, 2H, H +H ), 7.97 (d, J=1.7 Hz, 1H, H ), 8.40 (d, J=8.4 Hz, 1H, H ), 8.50 (d, J=8.1 Hz,
1
0
1
8
13
1
H, H ), 8.54 (d, J=5.3 Hz, 1H, H ), 8.58 (d, J=7.1 Hz, 1H, H ). C NMR (CDCl , 125 MHz): δ
3
1
64.63, 164.16, 157.32, 152.02, 134.79, 132.64, 131.17, 130.98, 130.60, 129.93, 128.77, 126.93,
26.29, 125.35, 125.22, 123.16, 120.88, 117.13, 115.95, 114.71, 99.08, 54.55, 43.23, 40.15, 29.01,
1
+
2
8.98, 28.76, 27.93, 26.95, 26.86, 26.23, 24.34. HRMS calcd for C H ClN O [M+1] 569.2605,
3
4
37
4
2
found 569.2698.
3
.3.6
2-(2-((7-chloroquinolin-4-yl)amino)ethyl)-6-morpholino-1H-benzo[de]isoquinoline-1,3(2H)-
dione (4f)
°
1
Yield-75%, dark green solid, M.P=165-170 C, H NMR (CDCl , 400 MHz): δ 3.24-3.26 (m, 4H,
3
CH -N-CH ), 3.64-3.67 (m, 2H, CH ), 3.98-4.00 (m, 4H, CH -O-CH ), 4.64-4.67 (m, 2H, CH ), 6.36
2
2
2
2
2
2
2
7
(
d, J=5.4 Hz, 1H, H ), 6.49 (s, 1H, NH-exchangeable with D O), 7.21 (d, J=8.0 Hz, 1H, H ), 7.36 (dd,
2
4
3
9
5
6
J=1.8, 8.9 Hz, 1H, H ), 7.68-7.76 (m, 2H, H +H ), 7.86 (s, 1H, H ), 8.41 (d, J=8.4 Hz, 1H, H ), 8.44
1
10
8
13
(
d, J=5.5 Hz, 1H, H ), 8.56 (d, J=8.1 Hz, 1H, H ), 8.62 (d, J=7.3 Hz, 1H, H ). C NMR (CDCl , 100
3
MHz): δ 164.58, 164.21, 156.10, 151.46, 149.95, 134.85, 133.10, 131.42, 130.40, 129.67, 128.30,
1
3
27.10, 126.23, 125.89, 125.15, 122.85, 121.64, 117.71, 116.25, 115.10, 98.52, 66.45, 52.98, 41.01,
+
7.90. HRMS calcd for C H ClN O [M+1] 487.1459, found 487.1525.
2
7
23
4
3
3
.3.7 2-(3-((7-chloroquinolin-4-yl)amino)propyl)-6-morpholino-1H-benzo[de]isoquinoline-1,3(2H)-
dione (4g)
°
1
Yield-75%, light green solid, M.P=135-140 C, H NMR (CDCl , 500 MHz): δ 2.18-2.20 (m, 2H,
3
CH ), 3.31 (s, 4H, CH -N-CH ), 3.42-3.43 (m, 2H, CH ), 4.05 (s, 4H, CH -O-CH ), 4.37 (t, J=6.0 Hz,
2
2
2
2
2
2
2
2
1
H, CH ), 6.33 (s, 1H, NH-exchangeable with D O), 6.43 (d, J=5.4 Hz, 1H, H ), 7.26 (d, J=8.1 Hz,
2 2
7
4
9
5
H, H ), 7.39 (d, J=9.0 Hz, 1H, H ), 7.75 (dd, J=7.9, 7.8 Hz, 1H, H ), 7.92 (s, 1H, H ), 7.97 (d, J=9.0
3
6
1
10
Hz, 1H, H ), 8.46 (d, J=8.4 Hz, 1H, H ), 8.50 (d, J=5.3 Hz, 1H, H ), 8.59 (d, J=8.0 Hz, 1H, H ), 8.64
d, J=7.2 Hz, 1H, H8). 13C NMR (CDCl , 125 MHz): δ 165.01, 164.53, 156.15, 151.75, 149.90,
(
3
1
0

1
1
34.89, 133.03, 131.58, 130.59, 129.95, 128.32, 127.08, 126.10, 125.92, 125.30, 122.90, 121.59,
17.42, 116.53, 115.01, 98.64, 66.93, 53.47, 39.80, 37.46, 26.60. HRMS calcd for C H ClN O
3
2
8
25
4
+
[
M+1] 501.1615, found 501.4631.
3
.3.8
2-(4-((7-chloroquinolin-4-yl)amino)butyl)-6-morpholino-1H-benzo[de]isoquinoline-1,3(2H)-
dione (4h)
Yield-74%, light green solid, M.P=130-135 C, H NMR (CDCl , 400 MHz): δ 1.67-1.71 (m, 4H,
°
1
3
(
CH ) ), 3.12 (s, 4H, CH -N-CH ), 3.24-3.25 (m, 2H, CH ), 3.84 (s, 4H, CH -O-CH ), 4.10 (t, J=5.6
2 2 2 2 2 2 2
2
Hz, 2H, CH ), 6.10 (s, 1H, NH- exchangeable with D O), 6.40 (d, J=5.6 Hz, 1H, H ), 7.25 (d, J=8.2
2
2
7
4
9
5
Hz, 1H, H ), 7.35 (d, J=8.9 Hz, 1H, H ), 7.72 (dd, J=7.9, 8.0 Hz, 1H, H ), 7.90 (s, 1H, H ), 7.95 (d,
3
6
1
J=9.0 Hz, 1H, H ), 8.45 (d, J=8.3 Hz, 1H, H ), 8.50 (d, J=5.5 Hz, 1H, H ), 8.55 (d, J=8.1 Hz, 1H,
1
0
8
13
H ), 8.61 (d, J=7.8 Hz, 1H, H ). C NMR (CDCl , 100 MHz): δ 164.06, 163.53, 155.85, 151.74,
3
1
1
50.83, 148.79, 134.09, 132.61, 131.11, 130.94, 129.48, 127.36, 126.50, 125.64, 124.61, 124.60,
22.94, 117.73, 116.21, 115.44, 98.08, 66.70, 53.51, 42.70, 25.84, 25.81. HRMS calcd for
+
C H ClN O [M+1] 515.1772, found 515.1872.
2
9
27
4
3
3
.3.9
dione (4i)
Yield-74%, yellow solid, M.P=90-95 C, H NMR (CDCl , 400 MHz): δ 1.40-1.44 (m, 4H, (CH ) ),
2-(6-((7-chloroquinolin-4-yl)amino)hexyl)-6-morpholino-1H-benzo[de]isoquinoline-1,3(2H)-
°
1
3
2 2
1
.65-1.67 (m, 4H, (CH ) ), 3.21-3.25 (m, 6H, CH -N-CH + CH ), 3.91 (s, 4H, CH -O-CH ), 4.05 (t,
2 2 2 2 2 2 2
2
J=6.1 Hz, 2H, CH ), 6.32 (s, 1H, NH-exchangeable with D O), 6.40 (d, J=5.5 Hz, 1H, H ), 7.21 (d,
2
2
7
4
3
9
5
J=8.1 Hz, 1H, H ), 7.32 (d, J=8.8 Hz, 1H, H ), 7.65-7.71 (m, 2H, H +H ), 7.93 (s, 1H, H ), 8.42 (d,
6
1
10
8
13
J=8.2 Hz, 1H, H ), 8.51-8.54 (m, 2H, H +H ), 8.62 (d, J=7.3 Hz, 1H, H ). C NMR (CDCl , 100
3
MHz): δ 164.16, 163.95, 155.60, 151.83, 150.61, 147.96, 134.45, 132.60, 131.15, 130.90, 129.45,
1
3
27.10, 126.17, 125.60, 124.75, 124.56, 122.83, 117.95, 116.18, 115.21, 99.10, 66.65, 53.50, 42.81,
+
9.85, 28.12, 28.07, 26.83, 26.80. HRMS calcd for C H ClN O [M+1] 543.2085, found 543.2205.
3
1
31
4
3
3
.3.10 2-(8-((7-chloroquinolin-4-yl)amino)octyl)-6-morpholino-1H-benzo[de]isoquinoline-1,3(2H)-
dione (4j)
Yield-72%, light brown solid, M.P=85-90 C, H NMR (CDCl , 500 MHz): δ 1.44-1.47 (m, 8H,
°
1
3
(
CH ) ), 1.76-1.79 (m, 4H, (CH ) ), 3.27-3.29 (m, 4H, CH -N-CH ), 3.30-3.34 (m, 2H, CH ), 4.03-
2 4 2 2 2 2 2
4
6
.04 (m, 4H, CH -O-CH ), 4.18 (t, J=7.6 Hz, 2H, CH ), 5.08 (s, 1H, NH-exchangeable with D O),
2
2
2
2
2
7
4
.43 (d, J=5.3 Hz, 1H, H ), 7.24 (d, J=8.0 Hz, 1H, H ), 7.36 (d, J=8.9 Hz, 1H, H ), 7.69-7.73 (m, 2H,
3
9
5
6
1
10
H +H ), 7.96 (s, 1H, H ), 8.44 (d, J=8.3 Hz, 1H, H ), 8.53-8.55 (m, 2H, H +H ), 8.60 (d, J=7.3 Hz,
1
1
H, H8). 13C NMR (CDCl , 125 MHz): δ 164.44, 163.99, 155.63, 151.95, 134.83, 133.90, 132.49,
3
31.14, 130.04, 129.87, 128.72, 126.93, 126.16, 125.84, 125.24, 123.36, 120.89, 117.20, 117.11,
1
1

1
14.96, 99.07, 66.96, 53.45, 43.23, 40.22, 29.01, 28.99, 28.76, 27.92, 26.96, 26.86. HRMS calcd for
+
C H ClN O [M+1] 571.2398, found 571.2488.
3
3
35
4
3
3
.3.11
2-(2-((7-chloroquinolin-4-yl)amino)ethyl)-6-(4-(2-hydroxyethyl)piperazin-1-yl)-1H-
benzo[de]isoquinoline-1,3(2H)-dione (4k)
°
1
Yield-70%, dark green solid, M.P>250 C, H NMR (DMSO-d , 400 MHz): δ 2.54 (t, J=5.6 Hz, 2H,
6
CH -CH -OH), 2.74 (s, 4H, CH -N-CH ), 3.25 (s, 4H, CH -N-CH ), 3.57 (t, J=5.8 Hz, 2H, CH -CH -
2
2
2
2
2
2
2
2
OH), 3.60-3.62 (m, 2H, CH ), 4.27 (t, J=6.5 Hz, 2H, CH ), 4.50 (s, 1H, OH- exchangeable with D O),
2
2
2
2
7
6
.35 (d, J=5.6 Hz, 1H, H ), 7.20-7.25 (m, 2H, H + NH- exchangeable with D O), 7.35 (dd, J=2.1, 9.0
2
4
5
9
3
Hz, 1H, H ), 7.71 (d, J=2.0 Hz, 1H, H ), 7.73 (dd, J=7.6, 8.1 Hz, 1H, H ), 8.21 (d, J=8.9 Hz, 1H, H ),
.25-8.28 (m, 2H, H +H ), 8.35 (d, J=8.2 Hz, 1H, H ), 8.40 (d, J=7.3 Hz, 1H, H ). 13C NMR
1
6
10
8
8
(
DMSO-d , 100 MHz): δ 164.81, 164.35, 156.12, 151.75, 150.20, 134.72, 132.65, 131.18, 130.46,
6
1
5
29.75, 128.24, 126.96, 126.10, 125.26, 124.90, 122.74, 121.85, 117.30, 116.30, 114.15, 99.10, 60.56,
+
9.15, 53.61, 53.10, 40.95, 37.80. HRMS calcd for C H ClN O [M+1] 530.1881, found 530.1990.
2
9
28
5
3
3
.3.12
2-(3-((7-chloroquinolin-4-yl)amino)propyl)-6-(4-(2-hydroxyethyl)piperazin-1-yl)-1H-
benzo[de]isoquinoline-1,3(2H)-dione (4l)
°
1
Yield-70%, yellow solid, M.P=145-150 C, H NMR (DMSO-d , 500 MHz): δ 2.04-2.06 (m, 2H,
6
CH ), 2.53-2.54 (m, 2H, CH -CH -OH), 2.74 (s, 4H, CH -N-CH ), 3.21 (s, 4H, CH -N-CH ), 3.39-
2
2
2
2
2
2
2
3
.41 (m, 2H, CH ), 3.58 (t, J=5.9 Hz, 2H, CH -CH -OH), 4.17 (t, J=6.8 Hz, 2H, CH ), 4.50 (s, 1H,
2 2 2 2
2
7
OH- exchangeable with D O), 6.44 (d, J=5.4 Hz, 1H, H ), 7.25 (d, J=8.2 Hz, 1H, H ), 7.28 ( t, J=5.1
2
4
5
9
Hz, 1H, NH- exchangeable with D O), 7.35 (dd, J=2.0, 8.9 Hz, 1H, H ), 7.73-7.77 (m, 2H, H +H ),
2
3
6
1
8
1
1
1
.13 (d, J=9.0 Hz, 1H, H ), 8.31 (d, J=8.1 Hz, 1H, H ), 8.35 (d, J=8.5 Hz, 1H, H ), 8.38 (d, J=8.5 Hz,
1
0
8
13
H, H ), 8.41 (d, J=6.9 Hz, 1H, H ). C NMR (DMSO-d , 125 MHz): δ 164.14, 163.61, 156.12,
6
52.27, 150.38, 149.42, 134.69, 133.74, 132.61, 131.02, 129.57, 127.83, 126.31, 125.67, 124.38,
24.29, 122.99, 117.88, 115.86, 115.31, 99.11, 60.66, 59.06, 53.60, 53.13, 40.85, 38.17, 26.98.
+
HRMS calcd for C H ClN O [M+1] 544.2037, found 544.1860.
3
0
30
5
3
3
.3.13
2-(4-((7-chloroquinolin-4-yl)amino)butyl)-6-(4-(2-hydroxyethyl)piperazin-1-yl)-1H-
benzo[de]isoquinoline-1,3(2H)-dione (4m)
°
1
Yield-68%, brown solid, M.P=140-145 C, H NMR (DMSO-d , 400 MHz): δ 1.68-1.72 (m, 4H,
6
(
CH ) ), 2.55 (t, J=5.5 Hz, 2H, CH -CH -OH), 2.75 (s, 4H, CH -N-CH ), 3.20 (s, 4H, CH -N-CH ),
2 2 2 2 2 2 2 2
3
1
.30-3.35 (m, 2H, CH ), 3.55 (t, J=5.8 Hz, 2H, CH -CH -OH), 4.10 (t, J=5.1 Hz, 2H, CH ), 4.50 (s,
2 2 2 2
2
7
H, OH- exchangeable with D O), 6.35 (d, J=5.6 Hz, 1H, H ), 7.21-7.25 (m, 2H, H + NH-
2
4
5
9
exchangeable with D O), 7.35 (dd, J=2.1, 9.0 Hz, 1H, H ), 7.71-7.75 (m, 2H, H +H ), 8.21 (d, J=9.1
2
1
2

3
1
6
10
8
13
Hz, 1H, H ), 8.25-8.30 (m, 2H, H +H ), 8.35 (d, J=8.3 Hz, 1H, H ), 8.40 (d, J=7.5 Hz, 1H, H ). C
NMR (DMSO-d , 100 MHz): δ 164.61, 164.12, 156.09, 151.69, 150.10, 134.67, 132.68, 131.17,
6
1
9
5
30.53, 129.81, 128.17, 126.95, 126.04, 125.65, 124.97, 122.94, 121.94, 117.29, 116.31, 114.91,
+
8.84, 59.56, 58.02, 53.21, 53.01, 42.80, 39.46, 25.73, 25.44. HRMS calcd for C H ClN O [M+1]
3
1
32
5
3
58.2194, found 558.2113.
3
.3.14
2-(6-((7-chloroquinolin-4-yl)amino)hexyl)-6-(4-(2-hydroxyethyl)piperazin-1-yl)-1H-
benzo[de]isoquinoline-1,3(2H)-dione (4n)
°
1
Yield-68%, brown solid, M.P=85-90 C, H NMR (DMSO-d , 400 MHz): δ 1.36 (s, 4H, (CH ) ),
6
2 2
1
.57-1.62 (m, 4H, (CH ) ), 2.48-2.49 (m, 2H, CH -CH -OH), 2.68 (s, 4H, CH -N-CH ), 3.16 (s, 6H,
2 2 2 2 2 2
CH -N-CH + CH ), 3.53 (t, J=6.0 Hz, 2H, CH -CH -OH), 3.97 (t, J=7.1 Hz, 2H, CH ), 4.46 (s, 1H,
2
2
2
2
2
2
2
7
OH- exchangeable with D O), 6.37 (d, J=5.4 Hz, 1H, H ), 7.22-7.24 (m, 2H, H + NH-exchangeable
2
4
5
9
3
with D O), 7.36 (dd, J=2.2, 8.9 Hz, 1H, H ), 7.70-7.74 (m, 2H, H +H ), 8.20 (d, J=9.0 Hz, 1H, H ),
2
.27-8.31 (m, 2H, H +H ), 8.34 (d, J=8.4 Hz, 1H, H ), 8.38 (d, J=7.4 Hz, 1H, H ). 13C NMR
1
6
10
8
8
(
DMSO-d , 100 MHz): δ 164.05, 163.52, 156.18, 152.40, 150.57, 149.57, 133.83, 132.70, 131.11,
6
1
5
5
31.10, 129.60, 127.94, 126.47, 125.75, 124.63, 124.45, 123.04, 117.94, 115.93, 115.44, 99.10, 60.73,
+
9.10, 53.67, 53.18, 42.85, 39.89 28.13, 28.02, 26.85, 26.83. HRMS calcd for C H ClN O [M+1]
3
3
36
5
3
86.2507, found 586.2585.
3
.3.15
2-(8-((7-chloroquinolin-4-yl)amino)octyl)-6-(4-(2-hydroxyethyl)piperazin-1-yl)-1H-
benzo[de]isoquinoline-1,3(2H)-dione (4o)
°
1
Yield-67%, dark green solid, M.P=85-90 C, H NMR (DMSO-d , 400 MHz): δ 1.35 (s, 8H, (CH ) ),
6
2 4
1
4
2
.60-1.64 (m, 4H, (CH ) ), 2.46 (t, J=5.8 Hz, 2H, CH -CH -OH), 2.70 (s, 4H, CH -N-CH ), 3.15 (s,
2 2 2 2 2 2
H, CH -N-CH ), 3.37-3.39 (m, 2H, CH ), 3.55 (t, J=6.0 Hz, 2H, CH -CH -OH), 4.01 (t, J=6.9 Hz,
2
2
2
2
2
2
H, CH ), 4.52 (s, 1H, OH- exchangeable with D O), 6.36 (d, J=5.1 Hz, 1H, H ), 7.21-7.25 (m, 2H,
2
2
7
4
5
9
H + NH-exchangeable with D O), 7.36 (dd, J=2.1, 8.8 Hz, 1H, H ), 7.71-7.75 (m, 2H, H +H ), 8.22
2
3
1
6
10
(
d, J=8.5 Hz, 1H, H ), 8.25-8.31 (m, 2H, H +H ), 8.30 (d, J=8.2 Hz, 1H, H ), 8.35 (d, J=7.1 Hz, 1H,
H8). 13C NMR (DMSO-d , 100 MHz): δ 163.94, 163.53, 155.76, 151.91, 150.15, 149.14, 133.72,
6
1
1
32.61, 131.45, 131.10, 129.15, 127.90, 126.45, 125.81, 125.01, 124.60, 123.10, 117.84, 115.90,
15.25, 98.91, 60.84, 59.15, 53.72, 53.20, 43.29, 40.25, 29.10, 28.96, 28.45, 27.96, 26.90, 26.56.
+
HRMS calcd for C H ClN O [M+1] 614.2820, found 614.2889.
3
5
40
5
3
3
.4 Procedure for synthesis of conjugates 7a-j:
The synthesis was initiated by heating 1,8-naphthalic anhydride 1, with glycine 5 in dry DMF at
°
1
00 C in the presence of triethyl amine as base. The product obtained 6 (1 mmol) was then reacted
1
3

with quinoline diamine 2 (1 mmol) using coupling reagents EDC (1.1 eq), HOBt (1.2 eq) and DIEA
2 eq) in anhydrous DMF for 1h. The reaction was monitored using TLC and after its completion,
(
water was added to quench the reaction. The desired products precipitated out of the reaction mixture
which was filtered, washed with water and recrystallized in ethanol to yield the desired conjugates.
3
.4.1
yl)acetamide (7a)
Yield-90%, Off-white solid, M.P>250 C, H NMR (DMSO-d , 400 MHz): δ 3.37 (s, 2H, CH ), 3.62
N-(2-((7-chloroquinolin-4-yl)amino)ethyl)-2-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-
°
1
6
2
2
(
s, 2H, CH ), 4.64 (s, 2H, CH ), 6.51 (d, J= 5.4 Hz, 1H, H ), 7.30 (s, 1H, NH- exchangeable with
2 2
4
5
7
10
D O), 7.34 (dd, J= 2.2, 9.0 Hz, 1H, H ), 7.74 (d, J= 2.2 Hz, 1H, H ), 7.83-7.86 (m, 2H, H +H ), 8.09
2
3
1
6
8
9
11
13
(
d, J=9.1 Hz, 1H, H ), 8.36 (d, J=5.4 Hz, 1H, H ), 8.44-8.46 (m, 5H, H +H +H +H +NH). C NMR
(
DMSO-d , 100 MHz): δ 168.01, 163.89, 152.47, 150.51, 149.53, 135.10, 133.91, 131.87, 131.40,
6
1
28.04, 128.02, 127.80, 124.64, 124.40, 122.47, 117.91, 99.16, 43.04, 42.53, 37.91. HRMS calcd for
+
C H ClN O [M+1] 459.1146, found 459.1198.
2
5
19
4
3
3
.4.2
N-(3-((7-chloroquinolin-4-yl)amino)propyl)-2-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-
yl)acetamide (7b)
°
1
Yield-90%, Off-white solid, M.P=125-130 C, H NMR (DMSO-d , 400 MHz): δ 1.80-1.82 (m, 2H,
6
CH ), 3.18-3.20 (m, 2H, CH ), 3.25-3.28 (m, 2H, CH ), 4.62 (s, 2H, CH ), 6.50 (d, J= 5.3 Hz, 1H,
2
2
2
2
2
4
H ), 7.27 (s, 1H, NH- exchangeable with D O), 7.35 (dd, J= 2.1, 8.9 Hz, 1H, H ), 7.73 (d, J= 2.0 Hz,
2
5
7
10
3
1
1
H, H ), 7.82-7.85 (m, 2H, H +H ), 8.10 (d, J=9.0 Hz, 1H, H ), 8.37 (d, J=5.3 Hz, 1H, H ), 8.45-8.47
6
8
9
11
13
(
m, 5H, H +H +H +H +NH-exchangeable with D O). C NMR (DMSO-d , 100 MHz): δ 167.85,
2
6
1
63.31, 151.98, 150.40, 148.73, 135.01, 133.65, 131.87, 130.33, 128.10, 128.02, 127.80, 124.64,
+
1
24.40, 122.47, 116.91, 99.62, 41.85, 36.94, 28.31. HRMS calcd for C H ClN O [M+1] 473.1302,
2
6
21
4
3
found 473.1387.
3
.4.3
N-(4-((7-chloroquinolin-4-yl)amino)butyl)-2-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-
yl)acetamide (7c)
°
1
Yield-89%, Off-white solid, M.P=125-130 C, H NMR (DMSO-d , 400 MHz): δ 1.51-1.55 (m, 2H,
6
CH ), 1.60-1.65 (m, 2H, CH ), 3.10-3.14 (m, 2H, CH ), 3.23-3.27 (m, 2H, CH ), 4.61 (s, 2H, CH ),
2
2
2
2
2
2
6
.51 (d, J= 5.4 Hz, 1H, H ), 7.29 (s, 1H, NH- exchangeable with D O), 7.34 (dd, J= 2.2, 9.0 Hz, 1H,
2
4
5
7
10
3
H ), 7.74 (d, J= 2.1 Hz, 1H, H ), 7.83-7.85 (m, 2H, H +H ), 8.09 (d, J=9.1 Hz, 1H, H ), 8.35 (d,
J=5.3 Hz, 1H, H ), 8.44-8.48 (m, 5H, H +H +H +H +NH-exchangeable with D O). 13C NMR
1
6
8
9
11
2
(
DMSO-d , 100 MHz): δ 168.10, 162.97, 152.47, 150.51, 149.53, 135.10, 133.59, 131.87, 131.40,
6
1
4

1
28.44, 128.02, 127.80, 124.64, 124.40, 123.47, 117.61, 98.45, 42.98, 42.50, 38.68, 27.25, 25.48.
+
HRMS calcd for C H ClN O [M+1] 487.1459, found 487.1501.
2
7
23
4
3
3
.4.4
yl)acetamide (7d)
Yield-90%, Off-white solid, M.P=230-235 C, H NMR (DMSO-d , 500 MHz): δ 1.31-1.44 (m, 6H,
N-(6-((7-chloroquinolin-4-yl)amino)hexyl)-2-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-
°
1
6
(
CH ) ), 1.62-1.68 (m, 2H, CH ), 3.06-3.10 (m, 2H, CH ), 3.22-3.26 (m, 2H, CH ), 4.63 (s, 2H, CH ),
2 3 2 2 2 2
2
6
.44 (d, J= 5.5 Hz, 1H, H ), 7.26 (t, J=5.2 Hz, 1H, NH- exchangeable with D O), 7.40 (dd, J= 2.2, 9.0
2
4
5
7
10
Hz, 1H, H ), 7.74 (d, J= 2.2 Hz, 1H, H ), 7.84-7.87 (m, 2H, H +H ), 8.16 (t, J= 5.5 Hz, 1H, NH-
3
1
exchangeable with D O), 8.25 (d, J=9.0 Hz, 1H, H ), 8.36 (d, J=5.4 Hz, 1H, H ), 8.46-8.48 (m, 4H,
2
6
8
9
11 13
H +H +H +H ). C NMR (DMSO-d , 125 MHz): δ 166.90, 163.80, 152.33, 150.51, 149.52, 134.92,
6
1
3
33.75, 131.79, 131.20, 127.98, 127.89, 127.66, 124.54, 124.36, 122.49, 117.88, 99.03, 42.92, 42.74,
+
8.98, 29.50, 28.21, 26.70, 26.47. HRMS calcd for C H ClN O [M+1] 515.1772, found 515.1825.
2
9
27
4
3
3
.4.5
N-(8-((7-chloroquinolin-4-yl)amino)octyl)-2-(1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-
yl)acetamide (7e)
Yield-89%, Off-white solid, M.P=180-185 C, H NMR (DMSO-d , 400 MHz): δ 1.25-1.40 (m, 8H,
°
1
6
(
CH ) ), 1.62-1.64 (m, 4H, (CH ) ), 3.01-3.05 (m, 2H, CH ), 3.21-3.25 (m, 2H, CH ), 4.60 (s, 2H,
2 4 2 2 2 2
2
CH ), 6.50 (d, J= 5.3 Hz, 1H, H ), 7.32 (s, 1H, NH- exchangeable with D O), 7.35 (dd, J= 2.1, 9.1 Hz,
2
2
4
5
7
10
3
1
H, H ), 7.74 (d, J= 2.0 Hz, 1H, H ), 7.81-7.84 (m, 2H, H +H ), 8.10 (d, J=9.0 Hz, 1H, H ), 8.37 (d,
J=5.2 Hz, 1H, H ), 8.45-8.47 (m, 5H, H +H +H +H +NH-exchangeable with D O). 13C NMR
1
6
8
9
11
2
(
DMSO-d , 100 MHz): δ 167.15, 162.80, 152.33, 151.75, 149.50, 134.82, 133.45, 131.79, 130.20,
6
1
2
27.98, 127.89, 127.10, 124.54, 124.35, 122.49, 117.72, 99.03, 42.95, 42.71, 39.10, 29.50, 29.22,
+
9.15, 28.25, 26.95, 26.68. HRMS calcd for C H ClN O [M+1] 543.2085, found 543.2110.
3
1
31
4
3
3
.4.6
2-(6-bromo-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)-N-(2-((7-chloroquinolin-4-
yl)amino)ethyl)acetamide (7f)
Yield-88%, light brown solid, M.P>250 C, H NMR (DMSO-d , 500 MHz): δ 3.36 (s, 4H, (CH ) ),
°
1
6
2 2
2
4
1
1
1
.68 (s, 2H, CH ), 6.55 (d, J= 5.4 Hz, 1H, H ), 7.34 (s, 1H, NH- exchangeable with D O), 7.39 (dd, J=
2 2
4
5
9
.5, 8.9 Hz, 1H, H ), 7.78 (d, J= 1.7 Hz, 1H, H ), 8.03 (dd, J=7.7, 8.0 Hz, 1H, H ), 8.12 (d, J=9.0 Hz,
3
7
6
1
H, H ), 8.25 (d, J=7.8 Hz, 1H, H ), 8.34 (d, J=7.8 Hz, 1H, H ), 8.41 (d, J=5.3 Hz, 1H, H ), 8.47 (s,
1
0
8
13
H, NH- exchangeable with D O), 8.58 (d, J=7.2 Hz, 1H, H ), 8.61 (d, J=8.5 Hz, 1H, H ). C NMR
2
(
DMSO-d , 125 MHz): δ 167.78, 163.32, 163.27, 152.21, 150.59, 149.25, 133.95, 133.41, 132.26,
6
1
9
31.94, 131.63, 130.41, 129.89, 129.39, 128.96, 127.77, 124.62, 124.33, 123.15, 122.36, 117.81,
+
9.11, 43.08, 42.55, 37.91. HRMS calcd for C H BrClN O [M+1] 537.0251, found 537.0341 and
2
5
18
4
3
+
[
M+3] 539.0251, found 539.0346.
1
5

3
.4.7
2-(6-bromo-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)-N-(3-((7-chloroquinolin-4-
yl)amino)propyl)acetamide (7g)
°
1
Yield-87%, light brown solid, M.P>250 C, H NMR (DMSO-d , 400 MHz): δ 1.78-1.80 (m, 2H,
6
CH ), 3.15-3.18 (m, 2H, CH ), 3.27-3.30 (m, 2H, CH ), 4.54 (s, 2H, CH ), 6.40 (d, J= 5.5 Hz, 1H,
2
2
2
2
2
4
5
H ), 7.31-7.35 (m, 2H, H + NH-exchangeable with D O), 7.71 (d, J= 1.8 Hz, 1H, H ), 7.90 (dd,
2
9
7
3
6
J=7.6, 8.2 Hz, 1H, H ), 8.12 (d, J=7.9 Hz, 1H, H ), 8.17 (d, J=9.0 Hz, 1H, H ), 8.21-8.25 (m, 2H, H +
NH-exchangeable with D O), 8.28 (d, J=5.4 Hz, 1H, H ), 8.46-8.50 (m, 2H, H +H ). 13C NMR
1
8
10
2
(
DMSO-d , 100 MHz): δ 167.44, 164.15, 163.65, 157.32, 153.22, 150.51, 149.32, 134.86, 132.65,
6
1
9
31.19, 131.07, 129.81, 127.88, 126.35, 125.94, 124.61, 124.46, 123.03, 117.65, 115.45, 116.36,
+
8.75, 41.89, 36.96, 28.46. HRMS calcd for C H BrClN O [M+1] 551.0407, found 551.0494 and
2
6
20
4
3
+
[
M+3] 553.0407, found 553.0487.
3
.4.8
2-(6-bromo-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)-N-(4-((7-chloroquinolin-4-
yl)amino)butyl)acetamide (7h)
°
1
Yield-86%, light brown solid, M.P=200-205 C, H NMR (DMSO-d , 400 MHz): δ 1.44-1.49 (m, 2H,
6
CH ), 1.55-1.60 (m, 2H, CH ), 3.05-3.09 (m, 2H, CH ), 3.18-3.23 (m, 2H, CH ), 4.55 (s, 2H, CH ),
2
2
2
2
2
2
4
6
1
8
.41 (d, J= 5.6 Hz, 1H, H ), 7.33-7.36 (m, 2H, H + NH-exchangeable with D O), 7.70 (d, J= 1.9 Hz,
2
5
9
7
3
H, H ), 7.91 (dd, J=7.7, 8.1 Hz, 1H, H ), 8.13 (d, J=7.8 Hz, 1H, H ), 8.17 (d, J=9.1 Hz, 1H, H ),
6
1
.20-8.23 (m, 2H, H + NH-exchangeable with D O), 8.29 (d, J=5.1 Hz, 1H, H ), 8.45-8.48 (m, 2H,
2
8
10 13
H +H ). C NMR (DMSO-d , 100 MHz): δ 167.15, 163.84, 163.25, 156.02, 152.19, 150.60, 133.85,
6
1
1
5
32.65, 131.14, 131.13, 129.62, 127.71, 126.56, 125.76, 124.87, 124.66, 124.47, 124.45, 123.05,
+
16.30, 115.51, 99.15, 42.87, 42.52, 38.70, 27.15, 25.42. HRMS calcd for C H BrClN O [M+1]
2
7
22
4
3
+
65.0564, found 565.0656 and [M+3] 567.0564, found 567.0656.
3
.4.9
2-(6-bromo-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)-N-(6-((7-chloroquinolin-4-
yl)amino)hexyl)acetamide (7i)
Yield-88%, light brown solid, M.P=180-185 C, H NMR (DMSO-d , 400 MHz): δ 1.30-1.41 (m, 6H,
°
1
6
(
CH ) ), 1.60-1.62 (m, 2H, CH ), 3.01-3.07 (m, 2H, CH ), 3.18-3.24 (m, 2H, CH ), 4.56 (s, 2H, CH ),
2 3 2 2 2 2
2
4
6
1
8
.42 (d, J= 5.6 Hz, 1H, H ), 7.30-7.34 (m, 2H, H + NH-exchangeable with D O), 7.71 (d, J= 1.9 Hz,
2
5
9
7
3
H, H ), 7.90 (dd, J=7.5, 8.0 Hz, 1H, H ), 8.10 (d, J=7.8 Hz, 1H, H ), 8.15 (d, J=9.0 Hz, 1H, H ),
6
1
.21-8.25 (m, 2H, H + NH-exchangeable with D O), 8.28 (d, J=5.4 Hz, 1H, H ), 8.43-8.46 (m, 2H,
2
8
10 13
H +H ). C NMR (DMSO-d , 100 MHz): δ 168.01, 163.87, 163.15, 156.20, 151.79, 150.60, 132.85,
6
1
1
32.45, 131.25, 131.10, 129.62, 127.70, 126.66, 125.26, 124.87, 124.50, 124.47, 124.45, 122.10,
16.30, 115.21, 99.05, 42.95, 42.75, 38.95, 29.61, 28.25, 26.71, 26.45. HRMS calcd for
+
+
C H BrClN O [M+1] 593.0877, found 593.4530 and [M+3] 595.0877, found 595.4524.
2
9
26
4
3
1
6

3
.4.10
yl)amino)octyl)acetamide (7j)
Yield-88%, light brown solid, M.P=145-150 C, H NMR (DMSO-d , 400 MHz): δ 1.20-1.35 (m, 8H,
2-(6-bromo-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)-N-(8-((7-chloroquinolin-4-
°
1
6
(
CH ) ), 1.60-1.62 (m, 4H, (CH ) ), 3.01-3.04 (m, 2H, CH ), 3.20-3.23 (m, 2H, CH ), 4.56 (s, 2H,
2
4
2 2
2
2
2
4
CH ), 6.40 (d, J= 5.5 Hz, 1H, H ), 7.30-7.35 (m, 2H, H + NH-exchangeable with D O), 7.68 (d, J=
2
2
5
9
7
2
.0 Hz, 1H, H ), 7.90 (dd, J=7.8, 8.1 Hz, 1H, H ), 8.12 (d, J=8.0 Hz, 1H, H ), 8.16 (d, J=9.0 Hz, 1H,
3
6
1
H ), 8.21-8.24 (m, 2H, H + NH-exchangeable with D O), 8.28 (d, J=5.3 Hz, 1H, H ), 8.45-8.49 (m,
2
8
10
13
2
1
1
H, H +H ). C NMR (DMSO-d , 100 MHz): δ 167.30, 163.98, 163.15, 157.28, 152.00, 150.72,
6
49.31, 133.94, 132.71, 131.15, 131.04, 128.81, 127.58, 126.62, 125.93, 124.61, 124.22, 123.00,
17.81, 115.46, 115.30, 99.10, 42.90, 42.71, 39.10, 29.45, 29.21, 29.10, 28.26, 27.02, 26.70. HRMS
+
+
calcd for C H BrClN O [M+1] 621.1190, found 621.1280 and [M+3] 623.1190, found 623.1285.
3
1
30
4
3
3
.5 Procedure for synthesis of conjugates 8a-o:
To a well stirred solution of 7 (for 7f-j, when R=Br) (1 mmol) in anhydrous NMP (1-2 mL), was
added different secondary amines (2 mmol) (piperidine/morpholine/hydroxyethyl piperazine) and the
°
reaction mixture was heated at 180 C for 1h. On completion of the reaction, as monitored from TLC,
ice cold water was added to the reaction mixture. The solid got precipitated out of the reaction
mixture which was then filtered, washed with water and recrystallized in ethanol to afford the desired
compounds 8a-o.
3
.5.1
N-(2-((7-chloroquinolin-4-yl)amino)ethyl)-2-(1,3-dioxo-6-(piperidin-1-yl)-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8a)
°
1
Yield-81%, dark green solid, M.P=225-230 C, H NMR (DMSO-d , 500 MHz): δ 1.65 (s, 2H, CH -
6
2
CH -CH ), 1.81 (s, 4H, CH -CH -CH ), 3.19 (s, 4H, CH -N-CH ), 3.36 (s, 4H, (CH ) ), 4.65 (s, 2H,
2
2
2
2
2
2
2
2 2
2
7
CH ), 6.54 (d, J= 5.4 Hz, 1H, H ), 7.28 (d, J= 8.2 Hz, 1H, H ), 7.31 (s, 1H, NH- exchangeable with
2
4
5
9
3
D O), 7.36 (dd, J= 1.9, 8.9 Hz, 1H, H ), 7.76-7.81 (m, 2H, H +H ), 8.10 (d, J=9.0 Hz, 1H, H ), 8.33
2
6
1
8
10
13
(
d, J=8.1 Hz, 1H, H ), 8.38-8.43 (m, 4H, H +H +H +NH). C NMR (DMSO-d , 125 MHz): δ
6
1
1
3
68.11, 163.99, 163.39, 157.35, 152.38, 150.45, 149.46, 133.81, 132.82, 131.23, 131.13, 129.82,
27.94, 126.24, 125.91, 124.54, 124.29, 122.89, 117.84, 115.32, 115.31, 99.09, 54.43, 42.80, 42.56,
+
7.86, 26.16, 24.31. HRMS calcd for C H ClN O [M+1] 542.1881, found 542.1971.
3
0
28
5
3
3
.5.2
N-(3-((7-chloroquinolin-4-yl)amino)propyl)-2-(1,3-dioxo-6-(piperidin-1-yl)-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8b)
°
1
Yield-80%, light green solid, M.P=165-170 C, H NMR (DMSO-d , 500 MHz): δ 1.65 (s, 2H, CH -
6
2
CH -CH ), 1.78-1.81 (m, 6H, CH -CH -CH + CH ), 3.19-3.21 (m, 6H, CH -N-CH + CH ), 3.26-
2
2
2
2
2
2
2
2
2
1
7

2
7
3
.30 (m, 2H, CH ), 4.64 (s, 2H, CH ), 6.48 (d, J= 5.5 Hz, 1H, H ), 7.29 (d, J= 8.2 Hz, 1H, H ), 7.32
2 2
4
5
(
s, 1H, NH- exchangeable with D O), 7.42 (dd, J= 2.2, 8.9 Hz, 1H, H ), 7.76 (d, J= 2.1 Hz, 1H, H ),
2
9
3
7
.80 (dd, J= 7.5, 8.2 Hz, 1H, H ), 8.23 (d, J=9.0 Hz, 1H, H ), 8.26 (t, J=5.6 Hz, 1H, NH-
6
1
exchangeable with D O), 8.36 (d, J= 8.1 Hz, 1H, H ), 8.39 (d, J=5.4 Hz, 1H, H ), 8.41 (d, J= 8.4 Hz,
2
1
0
8
13
1
1
1
H, H ), 8.45 (d, J= 7.2 Hz, 1H, H ). C NMR (DMSO-d , 125 MHz): δ 167.44, 164.05, 163.45,
6
57.32, 152.22, 150.53, 149.32, 133.86, 132.75, 131.19, 131.07, 129.85, 127.78, 126.27, 125.94,
24.51, 124.46, 123.00, 117.88, 115.45, 115.36, 99.15, 54.44, 42.86, 37.00, 28.32, 26.16, 24.30.
+
HRMS calcd for C H ClN O [M+1] 556.2037, found 556.2089.
3
1
30
5
3
3
.5.3
N-(4-((7-chloroquinolin-4-yl)amino)butyl)-2-(1,3-dioxo-6-(piperidin-1-yl)-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8c)
°
1
Yield-81%, pale yellow solid, M.P=150-155 C, H NMR (DMSO-d , 400 MHz): δ 1.50-1.54 (m, 2H,
6
CH ), 1.60-1.67 (m, 4H, CH + CH -CH -CH ), 1.80 (s, 4H, CH -CH -CH ), 3.10-3.14 (m, 2H, CH ),
2
2
2
2
2
2
2
2
2
2
3
.20-3.24 (m, 6H, CH + CH -CH -CH ), 4.60 (s, 2H, CH ), 6.45 (d, J= 5.3 Hz, 1H, H ), 7.30-7.34
2 2 2 2 2
7
4
(
m, 2H, H + NH-exchangeable with D O), 7.40 (dd, J= 2.0, 8.9 Hz, 1H, H ), 7.80 (d, J= 1.9 Hz, 1H,
2
5
9
H ), 7.82 (dd, J= 7.5, 8.0Hz, 1H, H ), 8.16 (t, J= 5.5 Hz, 1H, NH-exchangeable with D O), 8.25 (d, J=
2
3
6
1
10
8
9
.0 Hz, 1H, H ), 8.35-8.37 (m, 2H, H +H ), 8.46 (d, J= 7.0 Hz, 1H, H ), 8.49 (d, J= 8.5 Hz, 1H, H ).
1
3
C NMR (DMSO-d , 100 MHz): δ 167.08, 163.94, 163.39, 157.01, 152.18, 149.92, 132.85, 132.65,
6
1
1
31.14, 131.13, 129.76, 127.65, 126.56, 125.76, 124.61, 124.58, 124.47, 124.27, 123.07, 116.30,
15.61, 99.20, 54.10, 42.95, 42.50, 38.75, 27.21, 26.32, 25.56, 24.15. HRMS calcd for C H ClN O
3
3
2
32
5
+
[
M+1] 570.2194, found 570.2289.
3
.5.4
N-(6-((7-chloroquinolin-4-yl)amino)hexyl)-2-(1,3-dioxo-6-(piperidin-1-yl)-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8d)
°
1
Yield-80%, pale yellow solid, M.P=135-140 C, H NMR (DMSO-d , 400 MHz): δ 1.30-1.42 (m, 6H,
6
(
CH ) ), 1.61-1.68 (m, 4H, CH + CH -CH -CH ), 1.80 (s, 4H, CH -CH -CH ), 3.05-3.09 (m, 2H,
2 3 2 2 2 2 2 2 2
CH ), 3.18 (s, 4H, CH -CH -CH ), 3.21-3.25 (m, 2H, CH ), 4.60 (s, 2H, CH ), 6.45 (d, J= 5.4 Hz, 1H,
2
2
2
2
2
2
2
7
H ), 7.25 (d, J= 8.0 Hz, 1H, H ), 7.29 (t, J= 5.2 Hz, 1H, NH-exchangeable with D O), 7.37 (dd, J=
2
4
5
9
2
8
.0, 8.8 Hz, 1H, H ), 7.75-7.80 (m, 2H, H +H ), 8.12 (t, J= 5.4 Hz, 1H, NH-exchangeable with D O),
2
3
6
1
10
.26 (d, J= 8.9 Hz, 1H, H ), 8.31-8.35 (m, 2H, H +H ), 8.41 (d, J= 8.4 Hz, 1H, H ), 8.43 (d, J= 7.2
Hz, 1H, H8). 13C NMR (DMSO-d , 100 MHz): δ 168.01, 163.84, 163.15, 157.10, 152.19, 151.32,
6
1
1
33.85, 132.65, 132.04, 131.89, 129.62, 127.45, 126.56, 125.76, 124.95, 124.66, 124.51, 124.29,
23.10, 116.30, 115.51, 99.25, 54.15, 42.93, 42.70, 38.90, 29.45, 28.25, 26.71, 26.45, 26.15, 24.60.
+
HRMS calcd for C H ClN O [M+1] 598.2507, found 598.2590.
3
4
36
5
3
1
8

3
.5.5
N-(8-((7-chloroquinolin-4-yl)amino)octyl)-2-(1,3-dioxo-6-(piperidin-1-yl)-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8e)
°
1
Yield-79%, pale yellow solid, M.P=130-135 C, H NMR (DMSO-d , 500 MHz): δ 1.24-1.39 (m,
6
1
2
1
0H, (CH ) ), 1.63-1.64 (m, 4H, CH + CH -CH -CH ), 1.81 (s, 4H, CH -CH -CH ), 3.03-3.07 (m,
2 5 2 2 2 2 2 2 2
H, CH ), 3.17 (s, 4H, CH -CH -CH ), 3.22-3.26 (m, 2H, CH ), 4.59 (s, 2H, CH ), 6.44 (d, J= 5.5 Hz,
2
2
2
2
2
2
2
7
H, H ), 7.27 (d, J= 8.1 Hz, 1H, H ), 7.35 (s, 1H, NH- exchangeable with D O), 7.43 (dd, J= 2.1, 8.9
2
4
5
9
Hz, 1H, H ), 7.76 (d, J= 2.0 Hz, 1H, H ), 7.79 (dd, J= 7.6, 8.1 Hz, 1H, H ), 8.11 (t, J= 5.4 Hz, 1H,
3
6
NH- exchangeable with D O), 8.27 (d, J= 9.0 Hz, 1H, H ), 8.35 (d, J= 8.1 Hz, 1H, H ), 8.37 (d, J= 5.0
2
1
10
8
13
Hz, 1H, H ), 8.39 (d, J= 8.4 Hz, 1H, H ), 8.43 (d, J= 7.1 Hz, 1H, H ). C NMR (DMSO-d , 125
6
MHz): δ 166.97, 163.98, 163.39, 157.28, 152.00, 150.72, 149.12, 133.94, 132.71, 131.15, 131.04,
1
4
29.81, 127.58, 126.26, 125.93, 124.61, 124.49, 123.00, 117.81, 115.46, 115.33, 98.70, 54.42, 42.92,
2.70, 39.04, 29.48, 29.21, 29.10, 28.23, 27.00, 26.69, 26.15, 24.29. HRMS calcd for C H ClN O
3
6
40
5
3
+
[
M+1] 626.2820, found 626.2910.
3
.5.6
N-(2-((7-chloroquinolin-4-yl)amino)ethyl)-2-(6-morpholino-1,3-dioxo-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8f)
Yield-78%, mustard green solid, M.P=185-190 C, H NMR (DMSO-d , 500 MHz): δ 3.22-3.24 (m,
°
1
6
4
H, CH -N-CH ), 3.36 (s, 4H, (CH ) ), 3.91-3.93 (m, 4H, CH -O-CH ), 4.66 (s, 2H, CH ), 6.54 (d,
2 2 2 2 2 2 2
2
7
J= 5.4 Hz, 1H, H ), 7.34-7.36 (m, 2H, H + NH-exchangeable with D O), 7.38 (dd, J= 2.1, 9.0 Hz, 1H,
2
4
5
9
3
H ), 7.78 (d, J= 2.1 Hz, 1H, H ), 7.81 (dd, J= 7.8, 7.9 Hz, 1H, H ), 8.11 (d, J=9.0 Hz, 1H, H ), 8.37 (d,
6
1
J= 8.0 Hz, 1H, H ), 8.40 (d, J=5.3 Hz, 1H, H ), 8.42 (s, 1H, NH-exchangeable with D O), 8.45 (d, J=
2
1
0
8
13
7
1
1
.1 Hz, 1H, H ), 8.51 (d, J= 8.4 Hz, 1H, H ). C NMR (DMSO-d , 125 MHz): δ 168.07, 163.95,
6
63.38, 156.09, 152.21, 150.58, 149.24, 133.92, 132.75, 131.23, 129.76, 127.77, 126.56, 125.75,
24.61, 124.33, 122.96, 117.80, 116.17, 115.51, 99.10, 66.64, 53.51, 42.83, 42.57, 37.87. HRMS
+
calcd for C H ClN O [M+1] 544.1673, found 544.1765.
2
9
26
5
4
3
.5.7
N-(3-((7-chloroquinolin-4-yl)amino)propyl)-2-(6-morpholino-1,3-dioxo-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8g)
°
1
Yield-78%, light green solid, M.P=175-180 C, H NMR (DMSO-d , 400 MHz): δ 1.80-1.82 (m, 2H,
6
CH ), 3.20-3.24 (m, 6H, CH -N-CH + CH ), 3.25-3.28 (m, 2H, CH ), 3.91-3.93 (m, 4H, CH -O-
2
2
2
2
2
2
2
7
CH ), 4.62 (s, 2H, CH ), 6.47 (d, J= 5.4 Hz, 1H, H ), 7.30 (d, J=8.1 Hz, 1H, H ), 7.31 (s, 1H, NH-
2
2
4
5
exchangeable with D O), 7.40 (dd, J= 2.1, 8.8 Hz, 1H, H ), 7.75 (d, J= 2.1 Hz, 1H, H ), 7.81 (dd, J=
2
9
3
7
.4, 8.1 Hz, 1H, H ), 8.21 (d, J= 9.0 Hz, 1H, H ), 8.25 (s, 1H, NH-exchangeable with D O), 8.35 (d,
2
6
1
10
J= 8.0 Hz, 1H, H ), 8.38 (d, J=5.3 Hz, 1H, H ), 8.40 (d, J= 8.0 Hz, 1H, H ), 8.43 (d, J= 7.3 Hz, 1H,
H8). 13C NMR (DMSO-d , 100 MHz): δ 167.44, 164.10, 163.45, 157.12, 152.35, 150.53, 149.45,
6
1
33.86, 132.75, 131.74, 131.15, 130.05, 127.76, 126.17, 125.75, 124.57, 124.45, 122.95, 116.98,
1
9

+
1
5
15.45, 115.26, 98.95, 65.76, 52.62, 41.82, 36.92, 27.76. HRMS calcd for C H ClN O [M+1]
30 28 5 4
58.1830, found 558.1841.
3
.5.8
N-(4-((7-chloroquinolin-4-yl)amino)butyl)-2-(6-morpholino-1,3-dioxo-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8h)
°
1
Yield-76%, pale yellow solid, M.P=175-180 C, H NMR (DMSO-d , 500 MHz): δ 1.50-1.55 (m, 2H,
6
CH ), 1.62-1.68 (m, 2H, CH ), 3.11-3.15 (m, 2H, CH ), 3.21-3.23 (m, 4H, CH -N-CH ), 3.25-3.29
2
2
2
2
2
2
(
m, 2H, CH ), 3.90-3.92 (m, 4H, CH -O-CH ), 4.61 (s, 2H, CH ), 6.47 (d, J= 5.4 Hz, 1H, H ), 7.33-
2 2 2 2
7
4
5
7
7
.36 (m, 2H, H + NH-exchangeable with D O), 7.42 (dd, J= 2.1, 8.9 Hz, 1H, H ), 7.77 (s, 1H, H ),
2
9
.81 (dd, J= 7.6, 8.1 Hz, 1H, H ), 8.18 (t, J= 5.6 Hz, 1H, NH-exchangeable with D O), 8.26 (d, J=9.0
2
3
6
1
10
8
13
Hz, 1H, H ), 8.36-8.38 (m, 2H, H +H ), 8.45 (d, J= 7.1 Hz, 1H, H ), 8.50 (d, J= 8.4 Hz, 1H, H ). C
NMR (DMSO-d , 125 MHz): δ 167.08, 163.94, 163.39, 156.02, 152.18, 150.60, 133.85, 132.65,
6
1
1
5
31.14, 131.13, 129.76, 127.75, 126.56, 125.76, 124.57, 124.54, 124.47, 124.45, 123.07, 116.30,
+
15.51, 99.15, 66.64, 53.50, 42.78, 42.54, 38.80, 27.25, 25.60. HRMS calcd for C H ClN O [M+1]
3
1
30
5
4
72.1986, found 572.2052.
3
.5.9
N-(6-((7-chloroquinolin-4-yl)amino)hexyl)-2-(6-morpholino-1,3-dioxo-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8i)
°
1
Yield-76%, brown solid, M.P=155-160 C, H NMR (DMSO-d , 400 MHz): δ 1.31-1.45 (m, 6H,
6
(
CH ) ), 1.62-1.68 (m, 2H, CH ), 3.06-3.09 (m, 2H, CH ), 3.21-3.25 (m, 6H, CH + CH -N-CH ),
2 3 2 2 2 2 2
2
3
1
7
.90-3.92 (m, 4H, CH -O-CH ), 4.62 (s, 2H, CH ), 6.42 (d, J= 5.2 Hz, 1H, H ), 7.27 (d, J= 8.1 Hz,
2 2 2
7
4
H, H ), 7.31 (t, J= 5.1 Hz, 1H, NH-exchangeable with D O), 7.36 (dd, J= 2.0, 9.0 Hz, 1H, H ), 7.75-
2
5
9
.80 (m, 2H, H +H ), 8.16 (t, J= 5.4 Hz, 1H, NH-exchangeable with D O), 8.26 (d, J= 9.1 Hz, 1H,
2
3
6
1
10
8
13
H ), 8.32-8.35 (m, 2H, H +H ), 8.40 (d, J= 8.4 Hz, 1H, H ), 8.42 (d, J= 7.2 Hz, 1H, H ). C NMR
DMSO-d , 100 MHz): δ 167.10, 163.85, 163.51, 156.35, 152.18, 150.60, 133.85, 132.65, 132.14,
(
6
1
9
6
31.10, 129.76, 127.75, 126.16, 125.76, 124.57, 124.50, 124.41, 123.89, 123.07, 116.30, 115.35,
+
8.99, 66.49, 53.41, 42.70, 38.17, 29.91, 28.19, 26.74, 26.46. HRMS calcd for C H ClN O [M+1]
3
3
34
5
4
00.2299, found 600.2390.
3
.5.10
N-(8-((7-chloroquinolin-4-yl)amino)octyl)-2-(6-morpholino-1,3-dioxo-1H-
benzo[de]isoquinolin-2(3H)-yl)acetamide (8j)
°
1
Yield-75%, light brown solid, M.P=145-150 C, H NMR (DMSO-d , 500 MHz): δ 1.24-1.39 (m,
6
1
0H, (CH ) ), 1.62-1.66 (m, 2H, CH ), 3.03-3.07 (m, 2H, CH ), 3.20-3.26 (m, 6H, CH + CH -N-
2 5 2 2 2 2
2
CH ), 3.89-3.91 (m, 4H, CH -O-CH ), 4.60 (s, 2H, CH ), 6.45 (d, J= 5.5 Hz, 1H, H ), 7.32 (d, J= 8.0
2
2
2
2
7
4
Hz, 1H, H ), 7.40 (t, J= 4.6 Hz, 1H, NH-exchangeable with D O), 7.44 (dd, J= 2.0, 8.9 Hz, 1H, H ),
2
5
9
7
.76 (d, J= 2.1 Hz, 1H, H ), 7.80 (dd, J= 7.5, 8.1 Hz, 1H, H ), 8.12 (t, J= 5.3 Hz, 1H, NH-
2
0

3
6
1
exchangeable with D O), 8.27 (d, J= 9.0 Hz, 1H, H ), 8.37-8.38 (m, 2H, H +H ), 8.45 (d, J= 7.2 Hz,
2
1
0
8
13
1
1
1
2
H, H ), 8.49 (d, J= 8.4 Hz, 1H, H ). C NMR (DMSO-d , 125 MHz): δ 166.93, 163.92, 163.37,
6
56.00, 151.75, 150.85, 148.82, 134.06, 134.04, 132.63, 131.12, 129.74, 127.35, 126.54, 125.75,
24.63, 124.56, 123.05, 117.74, 116.29, 115.48, 98.10, 66.63, 53.49, 42.93, 42.72, 39.05, 29.48,
+
9.20, 29.10, 28.22, 27.00, 26.69. HRMS calcd for C H ClN O [M+1] 628.2612, found 628.2690.
3
5
38
5
4
3
1
.5.11 N-(2-((7-chloroquinolin-4-yl)amino)ethyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-1,3-dioxo-
H-benzo[de]isoquinolin-2(3H)-yl)acetamide (8k)
°
1
Yield-71%, dark green solid, M.P=180-185 C, H NMR (DMSO-d , 500 MHz): δ 2.54 (t, J= 6.1 Hz,
6
2
3
H, CH -CH -OH), 2.75 (s, 4H, CH -N-CH ), 3.23 (s, 4H, CH -N-CH ), 3.35-3.37 (m, 4H, (CH ) ),
2 2 2 2 2 2 2 2
2
.58 (t, J= 6.1 Hz, 2H, CH -CH -OH), 4.65 (s, 2H, CH ), 6.53 (d, J= 5.4 Hz, 1H, H ), 7.30 (d, J= 8.2
2
2
2
7
4
Hz, 1H, H ), 7.34 (s, 1H, NH-exchangeable with D O), 7.36 (dd, J= 2.1, 9.0 Hz, 1H, H ), 7.76-7.80
2
5
9
3
6
1
(
m, 2H, H +H ), 8.10 (d, J=9.0 Hz, 1H, H ), 8.34 (d, J= 8.1 Hz, 1H, H ), 8.39 (d, J=5.3 Hz, 1H, H ),
8
10
13
8
1
1
4
.41-8.44 (m, 3H, H +H +NH-exchangeable with D O). C NMR (DMSO-d , 125 MHz): δ 168.11,
2 6
63.96, 163.38, 156.32, 152.25, 150.54, 149.28, 133.89, 132.76, 131.18, 131.17, 129.76, 127.79,
26.39, 125.72, 124.59, 124.30, 122.89, 117.80, 115.70, 115.36, 99.09, 60.63, 59.02, 53.57, 53.11,
+
2.81, 42.57, 37.86. HRMS calcd for C H ClN O [M+1] 587.2095, found 587.2012.
3
1
31
6
4
3
1
.5.12 N-(3-((7-chloroquinolin-4-yl)amino)propyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-1,3-dioxo-
H-benzo[de]isoquinolin-2(3H)-yl)acetamide (8l)
°
1
Yield-71%, light green solid, M.P=180-185 C, H NMR (DMSO-d , 400 MHz): δ 1.81-1.83 (m, 2H,
6
CH ), 2.53 (t, J= 6.0 Hz, 2H, CH -CH -OH), 2.74 (s, 4H, CH -N-CH ), 3.19-3.24 (s, 6H, CH -N-
2
2
2
2
2
2
CH + CH ), 3.25-3.27 (s, 2H, CH ), 3.58 (t, J= 6.1 Hz, 2H, CH -CH -OH), 4.63 (s, 2H, CH ), 6.49
2
2
2
2
2
2
2
7
(
d, J= 5.5 Hz, 1H, H ), 7.30 (d, J= 8.1 Hz, 1H, H ), 7.32 (s, 1H, NH-exchangeable with D O), 7.41
2
4
5
9
(
dd, J= 2.1, 8.9 Hz, 1H, H ), 7.75 (d, J=2.1 Hz, 1H, H ), 7.80 (dd, J=7.6, 8.2 Hz, 1H, H ), 8.21 (d,
3
6
J=8.8 Hz, 1H, H ), 8.25 (s, 1H, NH-exchangeable with D O), 8.36 (d, J= 8.0 Hz, 1H, H ), 8.40 (d,
2
1
10
8
13
J=5.4 Hz, 1H, H ), 8.41 (d, J=8.5 Hz, 1H, H ), 8.43 (d, J=7.2 Hz, 1H, H ). C NMR (DMSO-d , 100
6
MHz): δ 167.34, 164.01, 163.65, 157.32, 152.22, 150.53, 149.32, 133.86, 132.84, 132.19, 131.21,
1
5
28.95, 127.76, 126.35, 125.91, 124.95, 124.48, 123.10, 117.81, 115.75, 115.37, 99.18, 60.26, 59.10,
+
3.21, 53.17, 43.02, 37.10, 27.86. HRMS calcd for C H ClN O [M+1] 601.2252, found 601.2267.
3
2
33
6
4
3
1
.5.13 N-(4-((7-chloroquinolin-4-yl)amino)butyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-1,3-dioxo-
H-benzo[de]isoquinolin-2(3H)-yl)acetamide (8m)
°
1
Yield-70%, light green solid, M.P=165-170 C, H NMR (DMSO-d , 400 MHz): δ 1.51-1.55 (m, 2H,
6
CH ), 1.61-1.65 (m, 2H, CH ), 2.53 (t, J= 6.0 Hz, 2H, CH -CH -OH), 2.75 (s, 4H, CH -N-CH ),
2
2
2
2
2
2
3
.10-3.14 (m, 2H, CH ), 3.21-3.27 (s, 6H, CH -N-CH + CH ), 3.57 (t, J= 6.1 Hz, 2H, CH -CH -OH),
2 2 2 2 2 2
2
1

2
7
4
7
.58 (s, 2H, CH ), 6.45 (d, J= 5.3 Hz, 1H, H ), 7.31-7.35 (m, 2H, H + NH-exchangeable with D O),
2 2
4
5
9
.41 (dd, J= 2.0, 8.9 Hz, 1H, H ), 7.75 (d, J=2.1 Hz, 1H, H ), 7.80 (dd, J=7.7, 8.0 Hz, 1H, H ), 8.15 (t,
3
6
1
J=5.5 Hz, 1H, NH-exchangeable with D O), 8.25 (d, J=9.0 Hz, 1H, H ), 8.35-8.37 (m, 2H, H +H ),
2
1
0
8
13
8
1
1
4
.43 (d, J=7.5 Hz, 1H, H ), 8.49 (d, J=8.1 Hz, 1H, H ). C NMR (DMSO-d , 100 MHz): δ 167.08,
6
64.94, 163.39, 156.02, 152.18, 151.60, 133.85, 132.65, 131.14, 130.13, 129.76, 126.75, 126.56,
25.76, 124.95, 124.54, 124.47, 124.45, 123.18, 116.30, 116.51, 98.75, 60.56, 59.10, 53.60, 53.15,
+
2.75, 42.50, 38.75, 27.27, 25.66. HRMS calcd for C H ClN O [M+1] 615.2408, found 615.2475.
3
3
35
6
4
3
1
.5.14 N-(6-((7-chloroquinolin-4-yl)amino)hexyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-1,3-dioxo-
H-benzo[de]isoquinolin-2(3H)-yl)acetamide (8n)
°
1
Yield-70%, yellow solid, M.P=145-150 C, H NMR (DMSO-d , 500 MHz): δ 1.32-1.44 (m, 6H,
6
(
CH ) ), 1.61-1.67 (m, 2H, CH ), 2.54 (t, J= 6.1 Hz, 2H, CH -CH -OH), 2.74 (s, 4H, CH -N-CH ),
2 3 2 2 2 2 2
3
.06-3.10 (m, 2H, CH ), 3.20-3.26 (m, 6H, CH + CH -N-CH ), 3.58 (t, J= 6.2 Hz, 2H, CH -CH -
2 2 2 2 2 2
2
7
OH), 4.61 (s, 2H, CH ), 6.43 (d, J= 5.5 Hz, 1H, H ), 7.26 (d, J= 8.1 Hz, 1H, H ), 7.30 (t, J= 5.3 Hz,
2
4
1
H, NH-exchangeable with D O), 7.38 (dd, J= 2.1, 8.9 Hz, 1H, H ), 7.74-7.78 (m, 2H,
2
5
9
3
H +H ), 8.15 (t, J= 5.5 Hz, 1H, NH-exchangeable with D O), 8.25 (d, J= 9.0 Hz, 1H, H ), 8.33-8.36
2
1
6
10
8
13
(
m, 2H, H +H ), 8.40 (d, J= 8.5 Hz, 1H, H ), 8.42 (d, J= 7.3 Hz, 1H, H ). C NMR (DMSO-d , 125
6
MHz): δ 167.06, 163.96, 163.38, 156.23, 152.06, 150.65, 149.19, 133.87, 132.64, 131.07, 129.75,
1
5
6
27.63, 126.37, 125.72, 124.55, 124.47, 124.42, 123.00, 117.80, 115.84, 115.33, 98.99, 60.64, 59.02,
+
3.57, 53.09, 42.71, 38.91, 29.50, 28.20, 26.62, 26.38. HRMS calcd for C H ClN O [M+1]
3
5
39
6
4
43.2721, found 643.2782.
3
1
.5.15 N-(8-((7-chloroquinolin-4-yl)amino)octyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-1,3-dioxo-
H-benzo[de]isoquinolin-2(3H)-yl)acetamide (8o)
°
1
Yield-68%, light brown solid, M.P=130-135 C, H NMR (DMSO-d , 400 MHz): δ 1.25-1.40 (m,
6
1
0H, (CH ) ), 1.61-1.65 (m, 2H, CH ), 2.52 (t, J= 5.8 Hz, 2H, CH -CH -OH), 2.72 (s, 4H, CH -N-
2 5 2 2 2 2
CH ), 3.01-3.05 (m, 2H, CH ), 3.21-3.27 (m, 6H, CH + CH -N-CH ), 3.56 (t, J= 5.9 Hz, 2H, CH -
2
2
2
2
2
2
2
7
CH -OH), 4.62 (s, 2H, CH ), 6.45 (d, J= 5.3 Hz, 1H, H ), 7.33 (d, J= 8.1 Hz, 1H, H ), 7.39 (t, J= 4.5
2
2
4
5
Hz, 1H, NH-exchangeable with D O), 7.45 (dd, J= 2.1, 8.8 Hz, 1H, H ), 7.78 (d, J= 2.0 Hz, 1H, H ),
2
9
7
.81 (dd, J= 7.6, 8.0 Hz, 1H, H ), 8.10 (t, J= 5.3 Hz, 1H, NH-exchangeable with D O), 8.28 (d, J= 9.0
2
3
6
1
10
8
13
Hz, 1H, H ), 8.35-8.37 (m, 2H, H +H ), 8.46 (d, J= 7.5 Hz, 1H, H ), 8.50 (d, J= 8.1 Hz, 1H, H ). C
NMR (DMSO-d , 100 MHz): δ 167.15, 163.98, 163.21, 157.28, 152.00, 150.70, 149.12, 133.94,
6
1
1
2
32.65, 131.15, 131.02, 129.81, 127.58, 126.26, 125.75, 124.61, 124.49, 123.02, 117.81, 115.46,
15.33, 98.95, 59.98, 59.10, 53.60, 53.10, 42.90, 42.70, 39.10, 29.50, 29.25, 29.12, 28.21, 27.02,
+
6.71. HRMS calcd for C H ClN O [M+1] 671.3034, found 671.3085.
3
7
43
6
4
2
2

3
3
.6 Material and Methods
.6.1 Bacterial culture conditions:
2
Mycobacterium tuberculosis strain mc 6230 was grown in Middlebrook 7H9 liquid broth (Difco)
supplemented with 10% OADC enrichment, 0.025% Tyloxapol and 24 µg/mL pantothenic acid [14].
Bacteria were placed in culture flasks to an optical density at 600 nm (OD ) of 0.05 and left to
6
00
incubate at 37°C for 1 week. Bacteria were harvested during the late exponential/early stationary
phase and adjusted to OD600 of 0.01 prior to transfer into 96-well plates for compound screening.
3
.6.2 Minimum Inhibitory Concentration (MIC):
Synthesized compounds were dissolved in DMSO (Dimethyl sulfoxide) and adjusted to a final
concentration of 10 mg/mL. To examine the biological activity of synthetic compounds, serial
dilutions were performed ranging from 200 µg to 0.39 µg/mL. Plates containing bacterial-synthetic
compound dilutions were placed back into the incubator at 37°C for 1 week. Following incubation,
1
0% (vol/vol) resazurin cell viability dye (0.025% stock concentration) was added to each well and
left to incubate at 37°C for 24 h prior to data acquisition using a fluorescent plate reader (excitation
40 nm, emission 590 nm). DMSO was included as a negative control, while INH was included as a
positive control at the pre-designated concentrations.
5
3
.6.3 Cell culture conditions:
Vero kidney epithelial cells (ATCC® CCL-81™) were cultured in RPMI 1640 cell culture medium
Life technologies) supplemented with 10% foetal calf serum and incubated at 37°C with 5% CO2.
(
Once the desired confluency was achieved, cells were detached from the flask surface using trypsin
and centrifuged at 220 x g for 5 min at room temperature to pellet cells. The cell pellet was
resuspended in 1 mL of culture medium and enumerated using a Malassez counting chamber. Cell
4
density was adjusted to approximately 2 x 10 cells/well in 96-well plates and left to adhere overnight
at 37°C and 5% CO2.
3
.6.4 Cytotoxicity assay:
To determine cytotoxicity of synthetic compounds, serial dilutions were performed ranging from 100
µg to 3.1 µg/mL. Cell cultures were placed back in the incubator at 37°C and 5% CO for 24 h. After
2
incubation, 10% (vol/vol) resazurin was added to each well and left to incubate at 37°C and 5% CO2
prior to data acquisition using a fluorescent plate reader (excitation 540 nm, emission 590 nm).
DMSO was included as a negative control, while 20% SDS was included as a positive control at the
pre-designated concentrations.
2
3

3
.6.5 Data analysis:
Data was analysed using Graphpad Prism 5 (Graphphad software). The half maximal inhibitory
concentration (IC ) was calculated using a non-linear regression dose response curve. Selectivity
5
0
Index (SI) was calculated as a function of the IC /MIC.
5
0
Acknowledgement: Financial assistance from the Department of Science and Technology (DST),
New Delhi, India, under INSPIRE programme (Shalini IF160180) is immensely valued.
Conflict of interest: The authors have declared no conflict of interest.
1
13
13
Electronic Supplementary Information: Scanned copies of H, C and C-DEPT NMR spectra of
representative compounds viz. 3c, 3d, 3e, 3i, 3j, 4c, 4e, 4g, 4j, 4l, 4n and 7a, 7d, 7f, 8a, 8b, 8e, 8h, 8j,
8
8
k, 8n along with scanned spectra of HRMS of few representative compounds viz. 3c, 3i, 4g, 4l, 7i,
g.
References:
1
. World
Health
Organization
(WHO).
Global
Tuberculosis
Report
2018.
https://apps.who.int/iris/bitstream/handle/10665/274453/9789241565646-eng.pdf?ua=1
2
3
. S. Chetty, M. Ramesh, A.S. Pillay, M.E.S. Soliman, Bioorg. Med. Chem. Lett. 27 (2017) 370.
. X.M. Chu, C. Wang, W. Liu, L.L. Liang, K.K. Gong, C.Y. Zhao, K.L. Sun, Euj. J. Med.
Chem. 161 (2019) 101.
4
5
. P. Singh, B. Jaiyeola, N. Kerru, O. Ebenezer, A. Bissessur, Curr. Med. Chem. 24 (2017)
4
180.
. (a) J. Cohen, Science. 339 (2013) 130.
(
(
(
b) https://www.ema.europa.eu/documents/overview/sirturo-epar-summary-public_en.pdf.
c) N.J. Ryan, J.H. Lo, Drugs 74 (2014) 1041.
d) https://www.ema.europa.eu/documents/overview/deltyba-epar-medicine-overview_en.pdf.
6
7
. A.H. Diacon, A. Pym, M.P. Grobusch, et al. N. Engl. J. Med. 371 (2014) 723.
. (a) M.V.N. de Souza, K.C. Pais, C.R. Kaiser, M.A. Peralta, M. de L. Ferreira, M.C.S.
Lourenço, Bioorg. & Med. Chem. 17 (2009) 1474. (b) A.M.L. Carmo, F.M.C. Silva, P.A.
Machado, A.P.S Fontes, F.R. Pavan, C.Q.F. Leite, S.R.A Leite, E.S. Coimbra, A.D. Da Silva,
Biomed. & Pharmacother. 65 (2011) 204. (c) L.M.R. Antinarelli, A.M.L. Carmo, F.R. Pavan,
C.Q.F Leite, A.D. Da Silva, E.S. Coimbra, D.B. Salunke, Org. Med. Chem. Lett. 2(2012) 16.
2
4

8
. (a) Y.Y. Zhang, C.H. Zhou, Bioorg. & Med. Chem. Lett. 21 (2011) 4349. (b) A. Kamal, N.R.
Bolla, P.S. Srikanth, A.K. Srivastava, Expert Opin. Ther. Patents 23 (2013) 299. (c) R.
Tandon, V. Luxami, H. Kaur, N. Tandon, K. Paul, Chem. Rec. 17 (2017) 956.
9
1
. H.H. Gong, D. Addla, J.S. Lv, C.H. Zhou, Curr. Top. Med. Chem. 16 (2016) 3303.
0. M.K. Machala, M. Nowosielski, A. Kuron, S. Rykowski, A. Olejniczak, M. Hoffmann, J.
Dziadek, Molecules 22 (2017) 154.
1
1. X. Nqoro, N. Tobeka, B.A. Aderibigbe, Molecules 22 (2017) 2268.
1
2. (a) Shalini, A. Viljoen, L. Kremer, V. Kumar, Bioorg. Med. Chem. Lett. 28 (2018) 1309. (b)
A. Singh, A. Viljoen, L. Kremer, V. Kumar, ChemistrySelect 3 (2018) 8511. (c) Shalini,
M.D. Johansen, L. Kremer, V. Kumar, Chem. Bio. & Drug Design 94 (2019) 1300. (d) A.
Rani, A. Viljoen, M. D. Johansen, L. Kremer, V. Kumar, RSC Advances, 9 (2019) 8515.
3. De Dibyendue, F.M. Krogstad, L.D. Byers, D.J. Krogstad, J. Med. Chem. 41 (1998) 4918.
4. 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, W.R. Jr Jacobs, Vaccine 24 (2006) 6309.
1
1
Captions:
Figure 1: Schematic diagram showing the design strategy for choosing the molecular fragments in the
synthesis of 1,8-naphthalimide-7-chloroquinoline hybrids.
Scheme 1: Synthesis of 1,8-naphthalimide-7-chloroquinoline hybrids 4 connected via simple alkyl
chains.
Scheme 2: Synthesis of 1,8-naphthalimide-7-chloroquinoline hybrids 8 connected via amide bond.
Table 1: In-vitro anti-mycobacterial and cytotoxic evaluation of the compounds against M.
2
tuberculosis mc 6230 and Vero kidney cell line.
Figure 2: Diagrammatic representation of SAR of alkyl chain versus amide bond tethered 4-
substituted 1,8-naphthalimide-7-chloroquinoline hybrids.
2
5

Br
N
NO2
N
R
OH
O
O
N
O
N
HN
N
O
N
O
Cl
Pinafide
Bedaquiline
MDR-TB only
NO2
O
H
N
HO
HN
N
N
H
N
N
H
O
O
N
O
O
R
Cl
OH
N
Ethambutol
Mitonafide
Anti-TB drugs
New molecules proved
(Commercialized)
to be active against Mtb
Figure 1: Schematic diagram showing the design strategy for choosing the molecular fragments in the
synthesis of 1,8-naphthalimde-7-chloroquinoline hybrids.
R
R
HN
N
NH2
n
O
Cl
NMP
H
N
N
0
1
50 C, 2h
n
O
O
1
O
Cl
O
N
2
3
R=H, Br
n=2,3,4,6,8
Br
N
O
Cl
O
Cl
Secondary amine
NMP
H
N
n
H
N
N
N
n
0
O
N
180 C, 1h
O
N
3
4
H
N
O
=
N
N
N
H
N
H
H
OH
Scheme 1: Synthesis of 1,8-naphthalimide-7-chloroquinoline hybrids 4 connected via simple alkyl
chains.
2
6

R
R
Et3N
DMF
H2N
COOH
O
N
O
0
O
O
O
5
100 C, 5h
COOH
1
6
R=H, Br
R
Cl
HN nNH2
R
EDC-HOBt, DIPEA
DMF, RT, 1h
O
O
N
O
N
O
Cl
N
N
N
nN
H
H
COOH
O
2
7
6
n=2,3,4,6,8
Cl
Cl
Br
N
O
Secondary Amine
O
O
N
O
N
N
O
0
N
NMP, 180 C, 1h
N
nN
N
H
N
n
H
H
H
O
7
8
H
O
N
=
N
N
N
H
N
H
H
OH
Scheme 2: Synthesis of 1,8-naphthalimide-7-chloroquinoline hybrids 8 connected via amide bond.
Table-1: In-vitro anti-mycobacterial and cytotoxic evaluation of the compounds against M.
2
tuberculosis mc 6230 and Vero kidney cell line.
Code
Structure
MIC99a
IC50b
SIc
Code
7a
Structure
MIC99a
IC50b
SIc
3
a
b
O
O
O
H
Cl
N
N
N
HN
N
H
O
O
N
200
>100
>0.5
100
200
5.287
1.144
0.052
0.005
Cl
N
O
3
7b
7c
O
HN
N
N
O
N
O
N
N
N
25
1.305
0.052
H
H
Cl
O
Cl
Cl
3
c
O
O
O
H
N
N
N
HN
N
N
O
H
O
N
Cl
25
3.261
>100
0.130
12.5
25
1.41
0.112
0.068
3
d
7d
O
O
Cl
O
H
N
N
N
HN
N
N
H
O
O
N
Cl
12.5
>8
1.713
2
7

3
e
7e
7f
O
O
O
Cl
H
N
N
N
N
HN
N
H
O
N
O
1
2.5
>100
>8
25
2.374
0.094
Cl
Br
3
f
O
Br
O
Cl
O
N
H
HN
N
N
N
N
O
50
25
3.747
5.296
0.074
0.211
H
50
2.008
2.03
0.040
0.010
O
N
N
Cl
O
Br
3
g
7g
7h
O
HN
N
O
N
O
N
N
>200
H
H
O
Cl
Cl
N
Br
Br
Br
3
h
O
O
Cl
O
H
N
N
N
HN
N
H
O
O
N
2
5
7.096
>100
>100
0.283
>8
50
25
11.55
2.074
>100
0.231
0.082
>0.5
Cl
N
Br
3
i
7i
7j
O
Br
O
Cl
O
H
N
N
N
HN
N
N
H
O
12.5
O
N
Cl
3
j
O
Br
Br
N
HN
O
Cl
O
O
2
5
>4
H
>200
N
N
N
Cl
N
O
H
N
4
a
8a
O
N
N
N
O
Cl
O
HN
H
N
N
O
N
50
61.33
1.226
N
12.5
2.138
0.171
H
O
N
Cl
N
O
4
b
8b
N
HN
O
O
O
O
N
N
N
N
Cl
N
N
H
H
12.5
>100
>8
O
12.5
12.5
5.41
1.51
0.432
0.120
Cl
4
c
8c
N
N
N
O
Cl
HN
O
H
O
N
N
N
6.25
17.35
2.776
O
H
N
Cl
N
4
d
e
8d
O
N
N
N
O
Cl
HN
N
O
H
O
N
N
N
H
O
N
Cl
6
.25
>100
>100
>16
>2
12.5
50
22.84
>100
1.827
2
4
8e
8f
N
O
N
O
Cl
N
O
HN
H
N
N
O
50
50
N
H
O
N
Cl
N
O
O
4
f
O
N
N
N
O
Cl
HN
O
H
O
N
13.04
34.58
0.260
0.691
N
N
100
50
6.369
46.23
0.063
0.924
N
H
O
N
Cl
N
O
O
4
g
8g
8h
N
HN
O
O
N
O
O
N
5
0
N
N
Cl
N
N
H
H
O
O
Cl
O
O
4
h
N
N
N
O
Cl
HN
N
O
H
O
25
6.434
0.257
N
N
50
11.11
0.222
N
H
O
N
Cl
2
8

O
O
4
i
j
8i
8j
N
O
N
O
Cl
N
O
O
HN
N
H
N
N
O
12.5
>100
>8
N
H
50
27.83
0.556
O
N
Cl
O
O
4
N
N
N
O
Cl
HN
O
H
O
N
N
N
H
O
N
Cl
N
12.5
100
>100
>8
200
200
>100
0.5
OH
HO
4
k
N
8k
8l
N
O
N
N
N
O
O
Cl
HN
N
H
N
N
O
23.97
0.239
N
5.852
0.029
H
O
N
Cl
O
HO
N
4
l
N
HN
N
O
O
O
N
N
N
N
Cl
N
N
N
H
H
O
N
50
25
35.23
17.81
0.704
0.712
Cl
200
200
7.007
6.023
0.035
0.030
OH
OH
HO
N
N
4
m
8m
8n
O
N
O
Cl
N
O
HN
N
H
N
N
O
N
H
O
N
Cl
OH
HO
N
N
4
n
O
N
N
O
Cl
N
O
HN
H
N
N
O
N
H
O
N
Cl
N
12.5
12.5
7.684
0.614
8.416
200
200
9.594
6.009
0.047
0.030
OH
HO
N
N
4
o
8o
O
N
N
N
O
Cl
HN
O
H
N
O
N
N
H
O
N
Cl
N
>100
>100
H
O
N
NH2
INHd
0.01
N
a
b
c
d
MIC99 – Minimum inhibitory concentration (in g/mL)
IC50 – Inhibitory concentration or Cytotoxicity (in g/mL)
SI- Selectivity index (IC50/MIC)
INH-Reference drug (Isoniazid)
Secondary amine
viz. piperidine
preferred over H/Br
Amide bond reduced activity
and caused cytotoxicity
R
R
O
O
O
N
N
N
H
HN
O
O
NH
Longer alkyl chains preferred
for better anti-mycobacterial activity
No significant effect of chain length
on both activity and cytotoxicity
Cl
N
N
Cl
Figure 2: Diagrammatic representation of SAR of alkyl chain versus amide bond tethered 4-
substituted 1,8-naphthalimide-7-chloroquinoline hybrids.
2
9