Cytotoxicity, tyrosine kinase inhibition of novel pyran, pyridine, thiophene, and imidazole derivatives

Article abstract of DOI:10.1002/jhet.4010

In this work, we are interested to use multicomponent reactions of cyclohexan-1,3-dione with different reagents for synthesizing new derivatives of pyran, pyridine, thiophene, and imidazole with antitumor activities. Twenty-two newly synthesized derivatives were selected and tested for their anticancer potency. Several of these compounds exhibited quite interesting potencies toward three human tumor cell lines, namely NCI-H460 (non-small cell lung cancer), SF-268 (CNS cancer), and MCF-7 (breast adenocarcinoma), especially when compared to that of reference drugs, doxorubicin and 5-Fu.Compounds 5b, 5c, 7b, 9b, 14a, 16c, 18a, 19c, 20b, and 22b, were found to be the most cytotoxic compounds toward the selected cell lines. On the other hand, 7b, 14a, 16c, 19c, and 22b revealed high inhibitions toward the tyrosine kinases. Active compounds against VEGFR-2, 14a, 16c, and 19c, were docked inside VEGFR-2enzyme to show the interaction between the tested compounds and the amino acids of the active site.

Full text of DOI:10.1002/jhet.4010

Received: 24 November 2019
DOI: 10.1002/jhet.4010
Revised: 12 April 2020
Accepted: 17 April 2020
A R T I C L E
Cytotoxicity, tyrosine kinase inhibition of novel pyran,
pyridine, thiophene, and imidazole derivatives
1
2
1
1
Rasha A. Azzam
| Rafat M. Mohareb
| Maher H. Helal | Kholoud K. Eisa
1
Department of Chemistry, Faculty of
Abstract
Science, Helwan University, Cairo, Egypt
2
In this work, we are interested to use multicomponent reactions of
cyclohexan-1,3-dione with different reagents for synthesizing new derivatives
of pyran, pyridine, thiophene, and imidazole with antitumor activities.
Twenty-two newly synthesized derivatives were selected and tested for their
anticancer potency. Several of these compounds exhibited quite interesting
potencies toward three human tumor cell lines, namely NCI-H460 (non-small
cell lung cancer), SF-268 (CNS cancer), and MCF-7 (breast adenocarcinoma),
especially when compared to that of reference drugs, doxorubicin and 5-Fu.
Compounds 5b, 5c, 7b, 9b, 14a, 16c, 18a, 19c, 20b, and 22b, were found to be
the most cytotoxic compounds toward the selected cell lines. On the other
hand, 7b, 14a, 16c, 19c, and 22b revealed high inhibitions toward the tyrosine
kinases. Active compounds against VEGFR-2, 14a, 16c, and 19c, were docked
inside VEGFR-2enzyme to show the interaction between the tested com-
pounds and the amino acids of the active site.
Department of Chemistry, Faculty of
Science, Cairo University, Giza, Egypt
Correspondence
Rafat M. Mohareb, Department of
Chemistry, Faculty of Science, Cairo
University, Giza, Arkansas, Egypt.
Email: raafat_mohareb@yahoo.com
1
| INTRODUCTION
pyrrolo[1,2-a]quinoxalines and its derivatives show excellent
[11]
activities
agents,
HIV drugs,
and broad medical potency as antitumor
[
12]
[13]
Recently, multicomponent reactions (MCRs) have gained a
major interest due to their ability to produce final products
in the same reaction vessel, resulting from different compo-
nents. This has the major advantage of shortening the time,
as well as the efforts, normally required for multistep synthe-
sis.
the area of drug discovery in modern organic synthesis.
In addition, these reactions are characterized by high atom
economy and high selectivity products. The one-step syn-
thesis process also allows for the production of great number
of molecular structures with divers functionalities, which is
the reason they are labeled environmentally friendly. Fur-
thermore, nitrogen-containing heterocyclic rings can be
found in a variety of organic molecules, which make them
quite valuable in organic synthesis, such as quinoxalines,
adenosine A3 receptor modulator,
anti-
[
8]
[14]
and antiparasitic medicines.
These
compounds are known to be quite important for build-
[
15]
ing 5-HT3 receptor agonist agents.
Due to such great
challenge, recently our research group reported several
reactions of cyclic β-diketones to produce thaizoles and
thiophene derivatives. The produced compounds
showed high antiproliferative activities against cancer
cell lines together with high inhibitions toward tyrosine
[
1,2]
This type of reactions has found a great application in
[
3–5]
[6]
[
16–18]
kinases.
This encouraged us to make further stud-
ies through the synthesis of new heterocyclic com-
pounds followed by studying their antiproliferative
activities. Thus, the current study discusses the use of
the variety of multicomponent reactions, starting with
active methylene reagents, cyclohexan-1,3-dione, and
aromatic aldehydes to afford either pyran or pyridine
derivatives with potential antitumor activities.
[
7]
[8]
which is found in applications such as anti-HIV drugs,
anticancer agents, and anti-inflammatory drugs. So far,
[9]
[10]
J Heterocyclic Chem. 2020;1–19.
wileyonlinelibrary.com/journal/jhet
© 2020 Wiley Periodicals LLC.
1

2
AZZAM ET AL.
2
| RESULTS AND DISCUSSION
any of the aromatic aldehydes, 2a–c, along with
cyclohexan-1,3-dione, 3, in a medium of ethanol and
triethylamine to yield the 5,6,7,8-tetrahydro-4H-
chromenederivatives, 5a–c (Scheme 1). The reactions
proceeded through the intermediate formation of
In this work, multicomponent reactions are utilized to
produce, potentially, biologically active compounds.
4
-Methylacetoacetanilide 1 was allowed to react with
O
O
CH
2
C
NH
CH
3
X
CHO
+
+
COCH
3
O
3
1
2a, X = H
b, X = Cl
c, X = OCH3
1,4-dioxane
3
Et N
X
O
C
O
H
H
3
C
N
CH
H
3
C
OH
OH
4a-c
2
-H O
X
O
C
O
H
H
3
C
N
H
3
O
5
a, X = H
b, X = Cl
SCHEME 1 Synthesis of
compounds, 5a–c
c, X = OCH3

AZZAM ET AL.
3
acyclic, 4a–c. Chemical structures of compounds, 5a–c,
corresponding to two CH groups, a singlet at δ 4.50 ppm
corresponding to the pyran CH, a multiplet at δ 6.83 to
3
1
were confirmed using analytical and spectral data. H
NMR spectrum of compound, 5a, for example, showed
multiplet signals at δ 1.86 to 2.21 ppm corresponding to
7.20 ppm corresponding to the C H and C H groups,
6
5
6
4
and a singlet at δ 9.50 ppm for the NH group. In addition,
13
the three CH groups, two singlets atδ 2.24 and 2.34 ppm
the C NMR spectrum revealed the presence of three
2
O
O
CH2
C
NH
CH3
X
CHO
+
+
COCH3
O
1
2a, X = H
b, X = Cl
3
c, X = OCH3
1
,4-dioxane
NH4OAC
X
O
C
O
H3C
NH
CH
OH
H3C
NH2
6
a-c
-H2O
X
O
O
H3C
NH
H3C
N
H
7
a, X = H
b, X = Cl
SCHEME 2 Synthesis of
compounds, 7a–c
c, X = OCH3

4
AZZAM ET AL.
signals at 18.6, 36.9, and 39.6 ppm due to the presence of
cyclohexan-1,3-dione, 3 in 1,4-dioxane containing ammo-
nium acetate, yielded the 4,6,7,8-tetrahydroquinoline
derivatives, 7a–c (Scheme 2). The reactions proceeded
through the intermediate formation of 6a–c. The chemical
reaction of 5c with sulfur and either malononitrile or
ethyl cyanoacetate reagents, 8a or 8b, afforded thieno
[3,2-f]chromene-8-carboxamide derivatives, 9a and 9b,
respectively (Scheme 3).
the three CH groups, five signals at 48.5, 139.8, 140.3,
2
1
43.2, and 146.8 ppm indicating the presence of the
pyran C, signals at 128.3, 127.0, 126.3, 125.8, 124.8, 123.2,
22.9, and 122.3 ppm for the C H and C H , and two sig-
1
6
5
6
4
nals at 166.3 and 164.2 ppm for the two CO groups.
Alternatively, the reaction of 4-methylacetoacetanilide 1
with any of the aromatic aldehydes, 2a–c, along with
OCH3
O
O
H
N
H C
3
S8
+
+
H C CN
2
H C
O
3
R
5
c
8a, R = CN
b, R = COOEt
1
,4-dioxane
Et N
3
OCH3
NH2
R
O
H
N
S
H C
3
H C
O
3
9
a, R = CN
b, R = COOEt
O
C
O
H N
N
2
Ph
CH2
COOEt
+
Ph
C
CH2
H N
N
H
1
0
2
1
1
1
2
SCHEME 3 Synthesis of compounds, 9a,b and 12

AZZAM ET AL.
5
β-Diketones were used to synthesize benzo[d]imidazole
along with cyclohexan-1,3-dione in a medium of 1,4-dioxane
with triethylamine to produce the corresponding 3-(1H-
benzo[d]imidazol-2-yl)-7,8-dihydro-4H-chromene deriv-
atives, 14a–c (Scheme 4). The chemical structures of
14a–c were confirmed using both spectral and analyti-
derivatives by the reaction of ethyl benzoylacetate 10 with
ꢀ
o-phenylenediamine 11 at 120 C, using an oil bath to afford
the 2-(1H-benzo[d]imidazol-2-yl)-1-phenylethanone 12 in a
good yield. Compound 12 was used in a multicomponent
reaction, involving one of the aromatic aldehydes, 2a–c,
1
cal data. For example, H NMR spectrum of 14a
O
O
N
Ph
C
CH2
+
X
CHO
+
N
H
O
12
2a, X = H
b, X = Cl
3
c, X = OCH3
EtOH/Et3N
X
N
O
CH
N
H
Ph
OH
OH
1
3a-c
-
H O
2
X
N
O
N
H
Ph
O
1
4a, X = H
b, X = Cl
SCHEME 4 Synthesis of
compounds, 14a–c
c, X = OCH3

6
AZZAM ET AL.
revealed
a
multiplet at
δ
2
2.24 to 2.28 ppm
confirming the presence of CO and CN groups,
respectively.
corresponding to the three CH groups, a singlet at δ
4
.58 ppm corresponding to the pyran CH group, a
Substituting the triethylamine reagent in the reac-
tion medium with ammonium acetate in a catalytic
amount yielded the corresponding 3-(1H-benzo[d]
imidazol-2-yl)-4,6,7,8-tetrahydroquinolinederivatives,
16a–c (Scheme 5).
multiplet at δ 7.18 to 7.55 ppm corresponding to the
two C H groups, and a singlet signal at δ 10.55 ppm
indicating the presence of the NH group. Moreover,
the C NMR spectrum of compound 14a showed three
signals at 18.1, 36.7, and 39.7 ppm corresponding to
the three CH groups, signals at 119.3, 121.5, 122.0,
1
1
due to the presence of two C H , C H , imidazole and
pyran carbons, and two signals at 164.6 and 167.7 ppm
6
5
1
3
The Knoevenagel reaction of compound 12 with
cyclohexan-1,3-dione 3 using a catalytic amount of ammo-
2
ꢀ
22.6, 123.6, 124.1, 124.7, 125.2, 126.3, 126.8, 127.1,
28.0, 139.8, 140.2, 140.8, 142.4, 142.6, and 142.8 ppm
nium acetate at 120 C afforded the condensate derivative
17. Both spectral and analytical data of derivative 17 con-
firmed its chemical structure. Gewald's thiophene synthesis
was then used to synthesize the thiophene derivatives via
6
5
6
4
O
O
N
Ph
C
CH2
+
X
CHO
+
N
H
O
2
a, X = H
b, X = Cl
c, X = OCH3
1
2
3
EtOH/NH OAc
4
X
N
O
CH
N
H
Ph
NH2 NH2
1
5a-c
-NH3
X
N
O
N
H
Ph
N
H
16a, X = H
b, X = Cl
c, X = OCH3
SCHEME 5 Synthesis of
compounds, 16a–c

AZZAM ET AL.
7
[
19–22]
compound 17.
Reaction of compound 17 with elemen-
with malononitrile 8a in 1,4-dioxane medium containing
triethylamine afforded the corresponding pyran derivatives
19a–c. Alternatively, similar reactions were carried out to
produce the 1,4,5,6,7,8-hexahydroquinoline derivatives,
20a–c, using ammonium acetate in place of triethylamine
tal sulfur and malononitrile 8a or ethyl cyanoacetate 8b
produced the corresponding 4,5,6,7-tetrahydrobenzo[b]thio-
phene derivatives, 18a,b. Multicomponent reactions of com-
pound 12 with any of the aromatic aldehydes, 2a–c, along
O
C
N
Ph
O
NH
O
O
N
NH OAc
4
Ph C CH2
NH
+
O
1
2
3
17
O
C
N
Ph
NH
EtOH
S8
+
CH CN
17
+
2
Et N
3
R
R
S
8
a, R = CN
b, R = COOEt
NH2
1
8a, R = CN
b, R = COOEt
CHO
EtOH
O
C
N
17 +
+
CH CN
2
Ph
Et3N
NH
CN
X
a, X = H
NH OAc
4
8
a
2
b, X = Cl
c, X = OCH3
O
C
N
O
Ph
NH
NH2
CN
X
1
9a, X = H
b, X = Cl
NH
c, X = OCH3
NH2
CN
X
2
0a, X = H
b, X = Cl
c, X = OCH3
SCHEME 6 Synthesis of
compounds, 17; 18a,b; 19a–c
and 20a–c

8
AZZAM ET AL.
(
1
Scheme 6). The multicomponent reaction of cyclohexan-
,3-dione 3 with malononitrile 8a and elemental sulfur pro-
Finally, the multicomponent reaction of 3-carbonitrile 21
with malononitrile 8a and any of the aromatic aldehydes, 2a–
c, afforded the corresponding 2,6-dihydro-4H-thieno[3,2-h]
chromene-3,7-dicarbonitrile derivatives 22a–c (Scheme 7).
duced the corresponding 2-amino-7-oxo-4,5,6,7-tetrahydro-
benzo[b]thiophene-3-carbonitrile 21.
O
O
S
1,4-dioxane
S8
H C
2
CN
NH2
+
+
Et N
3
CN
O
CN
3
8a
21
O
CHO
S
NH2
H C
2
CN
+
+
CN
CN
X
2
1
8a
2a, X = H
b, X = Cl
c, X = OCH3
1,4-dioxane
Et N
3
NH2
NC
O
S
NH2
X
CN
2
2a, X = H
b, X = Cl
c, X = OCH3
SCHEME 7 Synthesis of compounds 21 and 22a–c

AZZAM ET AL.
9
The chemical structures of derivatives 22a–c were con-
firmed using spectral and analytical data (see experimen-
tal section).
TABLE 1
the growth of the three human tumor cell lines
Influence of the newly synthesized compounds on
GI50 (μmolL−1
MCF-7
)
Compound
NCI-H460
4.52 ± 1.27
0.62 ± 0.18
0.81 ± 0.22
34.8 ± 0.38
0.72 ± 0.08
SF-268
5
5
5
7
a
b
c
a
2.64 ± 0.18
0.23 ± 0.13
0.69 ± 0.32
32.31 ± 2.26
0.64 ± 0.40
36.32 ± 6.82
70.5 ± 18.9
0.06 ± 0.005
0.08 ± 0.006
44.13 ± 8.27
22.28 ± 10.28
36.26 ± 6.51
2.09 ± 0.67
0.26 ± 0.07
4.52 ± 1.58
0.06 ± 0.002
18.32 ± 2.46
10.53 ± 2.26
20.4 ± 2.82
0.08 ± 0.002
22.4 ± 1.32
0.01 ± 0.005
22.8 ± 2.36
8.59 ± 2.16
16.39 ± 4.08
0.46 ± 0.12
31.21 ± 2.63
6.28 ± 1.31
0.75 ± 0.21
0.43 ± 0.15
30.5 ± 1.26
1.43 ± 0.09
2
2
.1 | Biology section
.1.1 | Antitumor evaluation
Three human tumor cell lines, namely NCI-H460 (non-
small cell lung cancer), SF-268 (CNS cancer), and MCF-7
7b
7
9
9
1
1
c
26.36 ± 6.41 22.83 ± 3.61
40.6 ± 12.18 50.4 ± 8.26
0.08 ± 0.004 0.04 ± 0.003
0.04 ± 0.003 0.01 ± 0.05
(breast adenocarcinoma) were used to prepare the cell
a
cultures. NCI-H460 and SF-268 cell lines were kindly
provided by the National Cancer Institute (NCI, Cairo,
Egypt). The MCF-7 cell line was obtained from the
European Collection of Cell Cultures (ECACC, Salisbury,
UK). To evaluate the influence of DMSO solvent on the
cell line growth, untreated control cells were exposed to a
maximum concentration of 0.5% DMSO that was used in
each assay.
b
4a
4b
23.53 ± 4.18
6.14 ± 8.53
14c
14.16 ± 4.26 12.24 ± 4.16
1
1
1
1
1
1
6a
6b
6c
7
22.08 ± 8.27
1.86 ± 0.85
0.36 ± 0.19
3.73 ± 0.16
0.41 ± 0.17
1.06 ± 0.69
0.36 ± 0.16
3.62 ± 1.52
8a
8b
0.03 ± 0.004 0.02 ± 0.01
14.53 ± 2.54 12.43 ± 1.72
2.1.2 | Tumor cell growth assay
In vitro evaluation of the antitumor activity of the synthe-
sized compounds was carried out by following the growth of
tumor cell lines according to the National Cancer Institute
19a
4.35 ± 1.38
8.28 ± 1.48
1
1
2
2
2
2
2
2
2
9b
9c
0a
0b
0c
1
36.1 ± 5.28 16.83 ± 4.58
0.07 ± 0.003 0.09 ± 0.002
22.63 ± 2.68 21.28 ± 3.69
0.06 ± 0.008 0.05 ± 0.006
(
NCI, USA) protocol. The anticancer drugs, doxorubicin and
-flourouracil, were used as the positive control and sub-
jected to the same protocol.
5
14.93 ± 2.48
6.73 ± 1.58
20.9 ± 3.68
5.93 ± 1.32
2.1.3 | Structure-activity relationship
2a
2b
2c
20.61 ± 8.25 18.22 ± 6.35
0.16 ± 0.02 0.84 ± 0.08
Table 1 clearly shows that compounds 5b, 5c, 7b, 9b, 14a,
6c, 18a, 19c, 20b, and 22b were the most active
compounds.
20.40 ± 4.53 18.42 ± 3.62
0.09 ± 0.008 0.09 ± 0.007
1
Doxorubicin 0.04 ± 0.008
-Fu 0.71 ± 0.04
5
0.33 ± 0.06
0.28 ± 0.08
Considering compounds 5a–c, it is clear that com-
pounds, 5b (X = Cl) and 5c (X = OCH ), were the most
3
cytotoxic compounds among the three compounds. Such
high cytotoxicity of these compounds resulted from the
low cytotoxicity. For the benzo[b]imidazole derivatives,
18a and 18b, it is obvious that 18a (R = CN) is more cyto-
toxic than 18b (R = COOEt). Multicomponent reactions
of derivative 17 with any of the aromatic aldehydes, 2a–c,
along with malononitrile 8a afforded the chromen-7(8H)-
ylidene)-2-oxo-2-phenylethyl)-1H-benzo[d]imidazole
derivatives 19a–c. It is clear from table 1 that compound
19c had the highest cytotoxicity among the other deriva-
impact of Cl and OCH groups present in these com-
3
pounds, respectively. It is apparent that among all
4
7
,6,7,8-tetrahydroquinoline derivatives, 7a-c, compound
b (X = Cl) had the highest activity with GI , 0.64, 0.72,
50
−
1
and 1.43 μmol . For the annulated compounds, 9a and
b, it is clear that compound 9b (R = COOEt), showed
9
higher cytotoxicity than derivative 9a (R = CN) and its
high potency was due to COOEt moiety present within
the compound. However, it is apparent that derivative
tives, possibly due to the presence of OCH group. How-
3
ever, in the case of the pyridine derivatives, 20a–c, it
was noticed that compound 20b (X = Cl) had the highest
cytotoxicity.4,5,6,7-Tetrahydrobenzo[b]thiophene deriva-
tive, 21, showed moderate inhibition against the three
1
4a (X = H) had the highest cytotoxicity among all the
pyran derivatives, 14a–c, although compounds, 14b and
4c, with (X = Cl) and (X = OCH ), respectively, showed
1
3

10
AZZAM ET AL.
TABLE 2
Compound
Inhibitory impact of compounds 5b, 5c, 7b, 9b, 14a, 16c, 18a, 19c, 20b, and 22b toward tyrosine kinases [Enzyme IC50 (nM)]
c-Kit
4.38
1.70
0.48
4.31
0.24
0.25
2.26
0.36
1.08
0.23
0.19
Flt-3
6.82
1.26
0.25
6.42
0.56
0.28
3.28
0.48
1.13
0.29
0.20
VEGFR-2
5.03
EGFR
6.26
1.53
0.32
8.53
0.42
0.83
5.38
0.41
2.36
0.35
0.28
PDGFR
8.96
1.28
0.26
3.31
0.29
0.62
3.26
0.54
1.29
0.31
0.39
5
5
7
9
1
1
1
1
2
2
b
c
1.17
b
0.61
b
5.96
4a
6c
8a
9c
0b
2b
0.26
0.15
4.62
0.25
1.42
0.46
Sorafenib
0.31
different cancer cell lines. Similarly, compound 22b
X = Cl) showed the highest cytotoxicity among the three
derivatives 22a–c. The study clearly shows that, in most
using Envision (PerkinElmer) at 320 and 615 nM. The
inhibition rate (%) was calculated using the mathematical
equation:
(
%
inhibition = 100−½ðActivity of enzyme with tested compounds−MinÞ=ðMax−MinÞꢁ × 100:
cases, the presence of an electronegative group, such as Cl
Max refers to the observed enzyme activity measured
in the presence of enzyme, substrates, and cofactors; Min
refers to the observed enzyme activity in the presence of
substrates, cofactors, and in the absence of enzyme. IC50
values were calculated using the inhibition curves.
The active compounds 5b, 5c, 7b, 9b, 14a, 16c, 18a, 19c,
20b, and 22b, were additionally assessed as enzyme inhibi-
tors against five tyrosine kinase enzymes (c-Kit, Flt-3,
VEGFR-2, EGFR, and PDGFR), using a similar protocol (see
experimental section), using Sorafenib as the positive control
drug. Results of the study for the different compounds
against the five tyrosine kinases are shown in Table 2.
atom or OCH group, resulted in high cytotoxic reactivity
3
of the compounds. It is of great value to mention that com-
pounds 5b, 5c, 7b, 9b, 14a, 16c, 18a, 19c, 20b, and 22b showed
inhibitions higher than 5-Fu toward MCF-7 cell line. On
the other hand, compounds 9b, 14a, 20b, and 22b revealed
higher inhibitions than 5-Fu toward NCI- H460 cell line.
2
.1.4 | Inhibitory impact of compounds
5b, 5c, 7b, 9b, 14a, 16c, 18a, 19c, 20b, and 22b
toward tyrosine kinase enzymes
It is apparent from Table 2 that derivatives, 7b
(X = Cl), 14a (X = H), 16c (X = OCH ), 19c (X = OCH ),
Tyrosine kinase enzyme assay protocol
3
3
Poly (Glu, Tyr) 4:1 (Sigma) 20 μg/mL was used as a sub-
strate in 384-well plates. Then, 50 μL of 10 mMATP
and 22b (X = OCH ), revealed high inhibitions toward
3
the tyrosine kinases with IC 's 0.48, 0.24, 0.25, 0.36, and
50
(
Invitrogen) solution, diluted in kinase reaction buffer
0.23 nM, respectively. On the other hand, derivatives, 5b
and 14a, show low inhibitions while compounds, 5c, 18a,
and 20b, had moderate inhibition impact.
(50 μM HEPES, Ph 7.0, 1 M DTT, 1 M MgCl , 1 M MnCl ,
2
2
and 0.1% NaN ), was added to each well. Various concen-
3
trations of the tested compounds, diluted in 10 μL of 1%
DMSO (v/v), were used as the negative control. The
kinase reaction was started by the addition of purified
tyrosine kinase proteins diluted in 39 μL of kinase reac-
tion buffer solution. The incubation time for the reactions
3 | MOLECULAR DOCKING STUDY
3.1 | Molecular docking
ꢀ
was 30 minutes at 25 C and ceased by the addition of 5 μL
of streptavidin-XL665 and 5 μL Tk Antibody Cryptate
working solution to all of wells. The plates were read
The molecular studies were carried out using Molecular
Operating Environment (MOE 2014). All the

AZZAM ET AL.
11
minimizations were performed with MOE until an RMSD
gradient of 0.01 K Cal/mol Å, with MMFF94X force field,
and the partial charges were automatically calculated.
Docking simulations were performed using the crystal
structure of VEGFR-2 (PDB ID: 4ASD) that was obtained
from Protein Data Bank. Enzyme structure was checked
for missing atoms, bonds, and contacts. Water molecules
were removed. Protonate 3D application of MOE was
used to add the missing hydrogens and properly assign
the ionization states. The ligand molecules were con-
structed using the builder molecule and were energy
minimized. The active site was generated using the
MOE-Alpha site finder. Ligands were docked within the
active sites using the MOE-Dock, and the generated poses
were energy minimized using the MMFF94x force field.
Finally, the optimized poses were ranked using the
GBVI/WSA DG free-energy estimates. Docking poses
were visually inspected and interactions with binding
pocket residues were analyzed.
Docking simulation was carried out to illustrate the
binding mode and the interaction of the active com-
pounds, 14a, 16c, and 19c, with the amino acids in the
active site of the VEGFR-2. Docking study was performed
using the crystal structure of VEGFR-2 (PDB ID:
[
23]
4ASD)
which has a co-crystallized ligand (sorafenib,
BAX) as inhibitor inside its active site. In the beginning,
FIGURE 1 A, 2D diagram; B, 3D diagram representation of co-crystallized ligand (sorafenib BAX) showing its interaction with the
VEGFR-2 receptor active site
FIGURE 2 A, 2D diagram; B, 3D diagram representation of compound, 14a, showing its interaction with the VEGFR-2 receptor active site

12
AZZAM ET AL.
FIGURE 3 A, 2D diagram; B, 3D diagram representation of compound, 16c, showing its interaction with the VEGFR-2 receptor
active site
FIGURE 4 A, 2D diagram; B, 3D diagram representation of compound, 19c, showing its interaction with the VEGFR-2 receptor
active site
the docking study was validated by re-docking of the
co-crystallized ligand (BAX) inside the active site of
VEGFR-2. The re-docking of the co-crystallized ligand,
BAX, was carried out to indicate the suitability of the
used protocol for the planned docking study. The valida-
tion method was achieved by removing the bound ligand
from the complex followed by its docking back into the bind-
ing site, which yielded root mean square deviation values
RMSD of 0.88 Å with energy score (S) -9.94 kcal/mol. The
top pose obtained from the MOE docking simulation showed
the interactions of the co-crystallized ligand, BAX, with the
key amino acids inside the active site (Ile1025, Asp1046,
Cys919, and Glu885), Figure 1.
It was clear from the docking study that the three
compounds revealed a binding pattern involving the
benzoimidazole moiety. The docking results showed
that compound, 14a, has binding energy of −5.64 kcal/mol
and exhibited only one hydrogen-bond donor, which is
formed between the NH of benzoimidazole ring, and the
CO group of Asp814 amino acid with a bond length of
2.99 Å, as shown in Figure 2. Concerning the docking study
of compounds, 16c and 19c, it showed that these

AZZAM ET AL.
13
compounds can fit into VEGFR-2 pocket with one
hydrogen bond, with Asp1046, similar to that of the co-
crystallized ligand BAX, with bond lengths of 2.76 and
was purchased from Cambrex, New Jersey, USA. L-
Glutamine and fetal bovine serum (FBS) were purchased
from Gibco Invitrogen Co. (Scotland, UK). Doxorubicin,
dimethyl sulfoxide (DMSO), streptomycin, sulforhodamine
B (SRB), and penicillin were supplied from Sigma
Chemicals, Saint Louis, USA.
2
.86 Å, respectively, shown in Figures 3 and 4. In case
of compound, 16c, the hydrogen-bond donor was
between the NH of the benzoimidazole ring and oxy-
gen of Asp1046 amino acid while the hydrogen-bond
acceptor in the case of compound, 19c, was between
the N of benzoimidazole ring with NH of Asp1046
amino acid. The binding energy of compounds, 16c
and 19c, scored −5.79 and−4.39 kcal/mol, respectively.
According to the above-mentioned data, the presence
of benzoimidazole moiety has played an important role to
bind with amino acids inside the pocket, which has pro-
vided a major explanation for the inhibition effect of com-
pounds 14a, 16c, and 19c toward VEGFR-2 enzyme.
5.1.1 | General procedure for the
synthesis of chromene derivatives, 5a–c
Either benzaldehyde (1.08 g, 0.01 mol), p-chlorobenzaldehyde
(1.40 g, 0.01 mol) or p-methoxybenzaldehyde (1.36 g,
0.01 mol) and cyclohexan-1,3-dione (1.12 g, 0.01 mol) were
added to a solution of 3-oxo-N-(p-toyl)butanamide (1.91 g,
0.01 mol) in 1,4-dioxane (40 mL) containing triethylamine
(
3
1.0 mL). The reaction mixture was heated under reflux for
hours then poured onto ice/water mixture, and the partici-
pated product was collected by filtration.
-Methyl-5-oxo-4-phenyl-N-(p-tolyl)-5,6,7,8-tetrahydro-
4H-chromene-3-carboxamide (5a). Pale yellow, yield 80%,
4
| CONCLUSIONS
2
In conclusion, a new series of pyran and thiophene deriv-
atives were developed. The obtained compounds demon-
strated greater activity against human tumor cell lines
such as SF-268 NCI-H460 and MCF-7 cell lines. The
results indicated that derivatives 5b, 5c, 7b, 9b, 14a, 16c,
ꢀ
−1
Mp 179-186 C. IR (KBr) ν max (cm ): 3480-3316 (NH),
3030 (CH-aromatic), 2953 (CH-aliphatic), 1720 (CO),
1
1606 (HNCO), 1530 (CC). H NMR (DMSO-d , 300 MHz):
6
δ 1.86-2.21 (m, 6H, 3CH ), 2.34, 2.68 (2s, 6H, 2CH ), 4.50
2
3
1
8a, 19c, 20b, and 22b, had the highest activity and were
(s, 1H, CH- pyran), 6.83-7.20 (m, 9H, C H , C H ), 9.50
6 5 6 4
13
tested for possible enzyme inhibition impact against tyro-
sine kinase enzymes (c-Kit, Flt-3, VEGFR-2, EGFR, and
PDGFR). Compounds 7b, 14a, 16c, 19c, and 22b showed
the highest inhibition values. Docking simulation of the
most potent compounds 14a, 16c, and 19c, against the
VEGFR-2 enzyme showed interactions with the Asp1046
and Asp814 amino acids inside the binding pockets of
VEGFR-2 enzyme, which explains their inhibition effect.
(s, 1H, NH). C NMR (DMSO-d , 75 MHz): δ 16.8, 18.6,
6
21.3, 36.9, 39.6 (3CH2, 2CH ), 48.5, 139.8, 140.3, 143.2,
3
146.8 (pyran C),128.3, 127.0, 126.3, 124.8, 124.8, 123.2,
122.9, 122.3 (C H , C H ), 166.3, 164.2 (2CO). EIMS: m/z
6
5
6
4
+
373[M] (26%); Anal. for C H NO (373.44): Calcd: C,
24
23
3
77.19; H, 6.21; N, 3.75%. Found: C, 77.28; H, 6.10; N, 3.50%.
4-(4-Chlorophenyl)-2-methyl-5-oxo-4-phenyl-N-(p-
tolyl)-5,6,7,8-tetrahydro-4H-chromene-3-carboxamide (5b).
ꢀ
Light brown, Mp 171-178 C, yield 72%. IR (KBr) ν max
−
1
(
cm ): 3477-3306 (NH), 3050 (CH-aromatic), 2938 (CH-
1
5
5
| EXPERIMENTAL
.1 | Chemistry
aliphatic),1664 (CO),1607 (HNCO), 1529 (CC). H NMR
DMSO-d , 300 MHz): δ1.89-2.26 (m, 6H, 3CH ), 2.21,
(
6
2
2.32 (2s, 6H, 2CH ), 4.55 (s, 1H, CH- pyran), 7.11-7.31
3
13
(
m, 8H, 2C H ), 10.18 (s, 1H, NH). C NMR (DMSO-d6,
6 4
The obtained compounds showed their melting points
using Electrothermal digital melting point apparatus and
are uncorrected. IR spectra (KBr discs) were measured on
a FTIR plus 460 or Pye Unicam SP-1000 spectrophotome-
75 MHz): δ 17.2, 18.9, 21.0, 36.7, 39.8 (3CH ,2CH ),
49.1139.5, 140.2, 143.8, 146.4 (pyran C), 122.0, 122.2,
2
3
123.6, 124.4, 125.9, 125.8, 127.2, 128.3 (C H , C H ),
6
5
6
4
+
164.1, 166.7 (2CO). EIMS: m/z 407[M] (23%); Anal. for
C H ClNO (407.89): Calcd: C, 70.67; H, 5.44; N, 3.43%.
1
ter (Pye Unicam, UK, Cambridge). H NMR spectra were
24
22
3
obtained from Varian Gemini-300 (300 MHz, Varian UK)
Found: C, 70.55; H, 5.38; N, 3.32%.
using DMSO-d as a solvent and Tetraethylsilane (TMS)
4-(4-Methoxyphenyl)-2-methyl-5-oxo-4-phenyl-N-(p-
tolyl)-5,6,7,8-tetrahydro-4H-chromene-3-carboxamide (5c).
6
as an internal standard. Chemical shifts are expressed as
δ ppm. The mass spectra were measured with Hewlett
Packard 5988 A GC/MS system (Hewlett Packard,
Agilent, USA) instrument.
ꢀ
Pale yellow, Mp 99-104 C, yield 65%. IR (KBr) ν max
−1
(cm ): 3417(NH), 3030 (CH-aromatic), 2947 (CH-
1
aliphatic),1658 (CO),1611 (HNCO), 1510 (CC). H NMR
Chemicals used for the screening processes were pur-
chased from international companies. RPMI-1640 medium
(DMSO-d , 300 MHz): δ 2.20-2.48 (m, 6H, 2CH ), 2.49,
6
2
2.63 (2s, 6H, 2CH ), 3.69 (s, 3H, OCH ), 4.55 (s, 1H, CH-
3
3

14
AZZAM ET AL.
13
pyran), 6.74-7.09 (m, 8H, 2C H ), 10.00 (s, 1H, NH).
C
300 MHz): δ2.03-2.21 (m, 6H, 3CH ), 2.48, (s, 3H, CH ),
6
4
2
3
NMR (DMSO-d , 75 MHz): δ 17.4, 18.7, 20.3, 36.5, 39.8
2.51 (s, 3H, CH ), 3.66 (s, 3H, OCH ), 4.91 (s, 1H, CH-
6
3 3
(
(
1
3CH ,2CH ), 52.6 (OCH ), 50.2, 139.3, 140.4, 143.5, 146.8
pyridine), 6.72-7.44 (m, 8H, 2C H ), 8.68 (s, 1H, NH),
6 4
2
3
3
13
pyran C),122.0, 122.6, 123.2, 124.4, 125.1, 125.2, 126.4,
49.9 (2C H ), 164.1, 166.7 (2CO). Anal. For C H NO
9.37 (s, 1H NH). C NMR (DMSO-d , 75 MHz): δ 18.3,
6
18.4, 21.6, 36.7, 39.8 (3CH , 2CH ), 52.4 (OCH ), 45.3,
6
4
25 25
4
2
3
3
(
7
403.47): Calcd: C, 74.42; H, 6.25; N, 3.47%. Found: C,
4.30; H, 6.30; N, 3.20%.
138.5, 139.4, 141.8, 143.6 (pyridine C), 121.5, 122.8, 123.9,
124.2, 125.9, 126.4, 127.1, 147.8 (2C H ), 164.3, 166.5
6
4
(
2CO). Anal. for C H N O (402.49): Calcd: C, 74.60; H,
25 26 2 3
6.51; N, 6.96%. Found: C, 74.40; H, 6.59; N, 6.77%.
5
.1.2 | General procedure for the
synthesis of hexahdroquinoline derivatives
a–c
7
5.1.3 | General procedure for the
synthesis of thieno[3,2-f]chromene
derivatives, 9a,b
Either benzaldehyde (1.08 g, 0.01 mol), p-chlorobenzaldehyde
1.40 g, 0.01 mol) or p-methoxybenzaldehyde (1.36, 0.01 mol)
(
and cyclohexan-1,3dione (1.12 g, 0.01 mol) were added to
a solution of 3-oxo-N-(p-toyl)butanamide (1.91 g, 0.01 mol)
in 1,4-dioxane (40 mL) containing ammonium acetate
Equimolar amounts of compound, 5c (4.03 g, 0.01 mol),
and each of sulfur (0.32 g, 0.01 mol) and either
malononitrile (0.66 g, 0.01 mol) or ethyl cyanoacetate
(1.07 g, 0.01 mol) and were dissolved in 1,4-dioxane
(50 mL) containing triethylamine (1.0 mL) was heated
under reflux for 2 hours. The reaction mixture was left to
cool and then poured onto an ice/water mixture, con-
taining a few drops of hydrochloric acid, and the partici-
pated product was collected by filtration.
(1.5 g, 0.01 mol). The reaction mixture was heated under
reflux for 5 hours then poured onto ice/water mixture, and
the participated product was collected by filtration.
2
-Methyl-5-oxo-4-phenyl-N-(p-tolyl)-1,4,5,6,7,8-
hexahdroquinoline-3-carboxamide (7a). Pale yellow, yield
ꢀ
−1
6
7%, Mp 145-148 C. IR (KBr) ν max (cm ): 3488-3361
(
1
6
NH), 3060 (CH-aromatic), 2940 (CH-aliphatic), 1688 (CO),
2-Amino-1-cyano-9-(4-methoxyphenyl)-7-methyl-N-
(p-tolyl)-5,9-dihydro-4H-thieno[3,2-f]chromene-8-carbox-
1
492 (CC). H NMR (DMSO-d , 300 MHz): δ2.03-2.22 (m,
6
ꢀ
H, 3CH ), 2.48, 2.50 (2s, 6H, 2CH ), 4.97 (s, 1H, CH-pyri-
amide (9a). Brown crystals, yield: 69%, Mp 134-138 C.
2
3
−1
dine), 7.02-7.43 (m, 9H, C H , C H ), 8.72, 9.41 (2s, 2H,
2
3
IR (KBr) ν max (cm ): 3420, 3324 (NH, NH ), 3030
6
5
6
4
2
13
NH). C NMR (DMSO-d , 75 MHz): δ17.9, 18.4, 21.8,
(CH-aromatic), 2946 (CH-aliphatic), 2205 (CN), 1656 (CO),
6
1
6.6, 38.2 (3CH ,2CH ),46.5, 139.5, 139.8, 141.6, 144.3 (pyri-
1509 (CC). HNMR (DMSO-d , 300 MHz): δ1.91-2.2 (m,
2
3
6
dine C),120.7, 122.3, 123.7, 124.4, 124.9, 126.1, 127.5, 128.1
4H, 2CH ), 2.25 (s, 3H, CH ), 2.28 (s, 3H, CH ), 3.69 (s, 3H,
2
3
3
+
(
C H , C H ), 166.8, 164.3(2CO). EIMS: m/z 372 [M] (35%);
OCH ), 4.52 (s, 1H, CH- pyran), 4.82 (s, 2H, NH ),
3 2
6
5
6
4
1
3
Anal. For C H N O (372.46): Calcd: C, 77.39; H, 6.49; N,
6.74-7.20 (m, 8H, 2C H ), 9.50 (s, 1H, NH). C NMR
6 4
24
24
2
2
7.52%. Found: C, 77.25; H, 6.34; N, 7.60%.
(DMSO-d , 75 MHz): δ17.6, 18.3, 21.5, 36.7 (2CH , 2CH ),
6
2
3
4
-(4-Chlorophenyl)-2-methyl-5-oxo-4-phenyl-N-(p-
50.0, 138.1, 139.7, 141.3, 143.3 (pyran C),118.2, 119.5,
120.1, 121.8, 122.9, 124.0, 124.3, 125.2, 126.5, 127.7, 135.0,
136.4 (thiophene and two C H ), 116.5 (CN), 162.5 (CO).
Anal. for C H N O S (483.58): Calcd: C, 69.54; H, 5.21;
28 25 3 3
N, 8.69%. Found: C, 69.43; H, 5.15; N, 8.78%.
tolyl)-1,4,5,6,7,8-hexahdroquinoline-3-carboxamide (7b).
ꢀ
Pale yellow, yield 70%, Mp 90-92 C. IR (KBr) ν max
6
4
−
1
(
cm ): 3468-3351 (NH), 3067 (CH-aromatic), 2943 (CH-
1
aliphatic), 1605 (CO), 1489 (CC). HNMR (DMSO-d ,
6
3
2
2
00 MHz): δ2.03-2.21 (m, 6H, 3CH ), 2.48, 2.49 (2s, 6H,
Ethyl 2-amino-9-(4-methoxyphenyl)-7-methyl-8-(p-
tolylcarbomoyl)-5,9-dihydro-4H-thieno[3,2-f]chromene-
2
CH ), 4.69 (s, 1H, CH- pyridine), 7.02-7.43 (m, 8H,
3
1
3
ꢀ
C H ), 8.78 (s, 1H, NH), 9.46 (s, 1H, NH). C NMR
1-carboxylate (9b). Pale yellow, yield 70%, Mp 139-144 C. IR
6
4
−1
(
DMSO-d , 75 MHz): δ18.0, 18.5, 21.0, 36.8, 38.1 (3CH ,
(KBr) ν max (cm ): 3427-3320 (NH, NH2), 2945
6
2
2
CH ), 44.9, 138.8, 139.6, 142.5, 143.8 (pyridine C),
(CH aromatic), 2838 (CH-aliphatic), 1710, 1657 (2CO), 1509
3
1
21.3, 121.9, 122.3, 124.9, 125.6, 126.2, 127.7, 128.1 (C H ,
(CC). (DMSO-d , 300 MHz): δ 1.12 (t, 3H, J = 7.5 Hz,
6
5
6
+
C H ), 164.4, 166.9 (2CO). EIMS: m/z 406 [M] (35%);
CH ), 1.30-1.96 (m, 4H, 2CH ), 2.17 (s, 3H, CH ), 2.21
6
4
3
2
3
Anal. for C H ClN O (406.90): Calcd: C, 70.84; H,
(s, 3H, CH ), 3.69 (s, 3H, OCH ), 4.25 (q, 2H, J = 7.5 Hz,
3 3
24
23
2
2
5
.70; N, 6.88%. Found: C, 70.80; H, 5.75; N, 6.82%.
-(4-Methoxyphenyl)-2-methyl-5-oxo-4-phenyl-N-(p-
CH ), 4.85 (s, 2H, NH ), 4.52 (s, 1H, pyran CH),
2 2
6.74-7.20 (m, 8H, 2C H ), 9.50 (s, 1H, NH). C NMR
6 4
1
3
4
tolyl)-1,4,5,6,7,8-hexahdroquinoline-3-carboxamide (7c).
(DMSO-d , 75 MHz): δ 16.2 (OCH CH ), 18.0, 18.3,
6
2
3
ꢀ
Pale yellow, yield 71%. Mp 128-130 C. IR (KBr) ν max
21.9, 36.7 (2CH ,2CH ), 50.6 (OCH CH ), 52.1(OCH ),
2 3 2 3 3
−
1
(
cm ): 3492-3386 (NH), 3067 (CH-aromatic), 2940 (CH-
50.4, 138.5, 139.4, 141.8, 143.6 (pyran C),118.6, 119.9,
120.2, 121.5, 122.6, 123.7, 124.3, 125.8, 126.0, 127.3,
1
aliphatic), 1604 (CO),1506 (CC). H NMR (DMSO-d ,
6

AZZAM ET AL.
15
1
35.4, 136.8 (thiophene and two C H ), 164.3, 166.9 (2CO).
3-(1H-Benzo[d]imidazol-2-yl)-4-(4-chlorophenyl)-
2-phenyl-7,8-dihydro-4H-chromen-5(6H)-one (14b). Pale
6
4
Anal. for C H N O S (530.63): Calcd: C, 67.90; H, 5.70; N,
30 30 2 5
ꢀ
−1
5.28%. Found: C, 67.69; H, 5.54; N, 5.43%.
yellow, yield: 75%, Mp 156-159 C. IR (KBr) ν max (cm ):
423 (NH), 3087, 3054 (CH-aromatic), 2932 (CH-ali-
3
1
phatic), 1666 (CO), 1517 (CC). H NMR (DMSO-d6,
5
.1.4 | Synthesis of 2-(1H-benzo[d]
300 MHz): δ2.24-2.50 (m, 6H, 3CH ), 4.55 (s, 1H, CH-
2
imidazol-2-yl)-1-phenylethanone (12)
pyran), 7.18-7.54 (m, 13H, 2C H , C H ), 10.00 (s, 1H,
6
4
6
5
13
NH). C NMR (DMSO-d , 75 MHz): δ 18.3, 36.4, 39.9
6
A dry mixture of equimolar amounts of ethyl ben-
(3CH ), 51.5, 120.7, 121.8, 122.5, 122.8, 123.9, 124.3,
2
zoylacetate (1.92 g, 0.01 mol) and o-phenylenediamine
124.5, 125.0, 126.8, 126.9, 127.6, 128.3, 139.5, 140.6, 141.3,
141.8, 143.6, 143.8 (C H , 2C H , imidazole, pyran C),
ꢀ
(1.09 g, 0.01 mol) was heated at 120 C in an oil bath for
6
5
6
4
+
1
0 minutes, and then the reaction mixture was left to
164.9 (CO), 167.8 (CN). EIMS: m/z 452 [M] (48). Anal.
for C H ClN O (452.93): Calcd: C, 74.25; H, 4.67; N,
cool. The formed solid product was triturated with dieth-
ylether, and then collected by filtration.
28
21
2 2
6.18%. Found: C, 74.05; H, 6.87; N, 6.30%.
Pale yellow crystals, yield 72% (1.69 g), Mp 180-
3-(1H-Benzo[d]imidazol-2-yl)-4-(4-methoxyphenyl)-2-phe-
nyl-7,8-dihydro-4H-chromen-5(6H)-one (14c). Pale yellow,
yield: 72%, Mp 144-148 C. IR (KBr) ν max (cm ): 3434
ꢀ
−1
1
83 C. IR (KBr) ν max (cm ): 3437 (NH), 3053 (CH aro-
1
ꢀ
−1
matic), 2974 (CH-aliphatic), 1680 (CO), 1515 (CC). H
NMR (DMSO-d , 300 MHz): δ 3.50 (s, 2H, CH ), 7.20-7.55
(NH), 3087, 3054 (CH-aromatic), 2932 (CH-aliphatic), 1680
6
2
1
(
m, 9H, C H , C H ), 10.45 (s, 1H, D O exchangeable,
(CO), 1517 (CC). H NMR (DMSO-d , 300 MHz): δ
6
5
6
4
2
6
13
NH). C NMR (DMSO-d , 75 MHz): δ 49.8 (CH ), 118.2,
2.22-2.53 (m, 6H, 3CH ), 3.65 (s, 3H, OCH ), 4.58 (s, 1H,
6
2
2
3
1
1
23.8, 124.9, 125.0, 126.0, 127.3, 128.3, 129.6, 130.2, 139.2,
CH-pyran), 7.23-7.56 (m, 13H, 2C H , C H ), 10.13 (s, 1H,
6 4 6 5
13
40.3 (two benzene, indole C), 164.8 (CO), 167.2 (CN).
NH). C NMR (DMSO-d , 75 MHz): δ 18.5, 36.6, 39.9
6
+
EIMS: m/z 236 [M] (90). Analysis for C H N O
(3CH ), 52.6 (OCH ), 52.5, 120.3, 121.2, 122.9, 123.3, 123.9,
15
12
2
2
3
(
7
236.27): Calcd: C, 76.25; H, 5.12; N, 11.86%. Found: C,
6.39; H, 4.82; N, 11.66%.
124.3, 124.5, 125.6, 126.8, 126.5, 127.9, 128.1, 139.1, 140.2,
141.3, 142.0, 142.8, 143.8 (C H , 2C H , imidazole, pyran
6
5
6 4
+
C), 164.8 (CO), 167.3 (CN). EIMS: m/z 448 [M] (40). Anal.
for C H N O (448.51): Calcd: C, 77.66; H, 5.39; N, 6.25%.
29 24 2 3
5
.1.5 | General procedure for the
synthesis of 7,8-dihydro-4H-chromen-5
6H)-one derivatives 14a–c
Found: C, 77.41; H, 5.44; N, 651%.
(
5.1.6 | General procedure for synthesis
Each of either benzaldehyde (1.08 g, 0.01 mol), p-
chlorobenzaldehyde (1.40 g, 0.01 mol) or p-
methoxybenzaldehyde (1.36 g, 0.01 mol), and cyclohexan-
,3-dione (1.12 g, 0.01 mol) were added to a solution of
compound, 12 (2.36 g, 0.01 mol), in 1,4-dioxane (40 mL)
containing triethylamine (1.0 mL). The reaction mixture
was heated under reflux for 3 hours and then poured onto
an ice/water mixture, and the participated product was col-
lected by filtration.
of 4,6,7,8-tetrahydroquinolin-5(1H)-one
derivatives, 16a–c
1
Each of either benzaldehyde (1.08 g, 0.01 mol), p-
chlorobenzaldehyde (1.40 g, 0.01 mol) or p-methoxyben-
zaldehyde (1.36 g, 0.01 mol), and cyclohexan-1,3-dione
(1.12 g, 0.01 mol) were added to a solution of compound,
12 (2.36 g, 0.01 mol), in 1,4-dioxane (40 mL) containing
ammonium acetate (1.50 g, 0.02 mol). The reaction mix-
ture was heated under reflux for 3 hours and then poured
onto an ice/water mixture, and the participated product
was collected by filtration.
3
-(1H-Benzo[d]imidazol-2-yl)-2,4-diphenyl-7,8-dihydro-
4
H-chromen-5(6H)-one (14a). Pale yellow, yield: 66%, Mp
ꢀ
−1
1
92-196 C. IR (KBr) ν max (cm ): 3492 (NH), 3056 (CH-
1
aromatic), 2962 (CH-aliphatic), 1661 (CO),1603 (CC). H-
3-(1H-Benzo[d]imidazol-2-yl)-2,4-diphenyl-4,6,7,8-
tetrahydroquinolin-5(1H)-one (16a). Pale yellow, yield:
NMR (DMSO-d , 300 MHz): δ 2.24-2.28 (m, 6H, 3CH ),
6
2
ꢀ
−1
4
1
3
1
1
.58 (s, 1H, CH-pyran),7.18-7.55 (m, 14H, 2C H , C H ),
74%, Mp 185-187 C. IR (KBr) ν max (cm ): 3387-3328
6
5
6
4
1
3
0.55 (s, 1H, NH). C NMR (DMSO-d , 75 MHz): δ 18.1,
(2NH), 3056 (CH-aromatic), 2960 (CH-aliphatic), 1661 (CO),
6
1
6.7, 39.7 (3CH ), 52.4, 119.3, 121.5, 122.0, 122.6, 123.6,
1603 (CC). H-NMR (DMSO-d , 300 MHz): δ2.22-2.29 (m,
2
6
24.1, 124.7, 125.2, 126.3, 126.8, 127.1, 128.0, 139.8, 140.2,
40.8, 142.4, 142.6, 142.8 (2C H , C H , imidazole, pyran
6H, 3CH ), 4.56 (s, 1H, CH-pyridine), 7.23-7.58 (m,
2
1
3
14H, 2C H , C H ), 9.25, 10.43 (2s, 2H, 2NH). C NMR
6
5
6
4
6
5
6
4
+
C), 164.6 (CO), 167.7 (CN). EIMS: m/z 418 [M] (68).
Anal. for C H N O (418.49): Calcd: C, 80.36; H,
(DMSO-d , 75 MHz): δ 18.4, 36.8, 39.7 (3CH ), 48.2,
6
2
120.6, 121.8, 122.4, 122.2, 122.8, 124.3, 124.5, 125.2,
28
22 2 2
5
.30; N, 6.69%. Found: C, 80.28; H, 5.19; N, 6.88%.
126.7, 126.8, 127.3, 128.0, 140.3, 140.8, 141.6, 141.9,

16
AZZAM ET AL.
1
1
42.4, 142.8 (2C H , C H , imidazole, pyridine C),
64.4 (CO), 167.9 (CN). EIMS: m/z 417 [M] (42). Anal.
C H N O (330.38): Calcd: C, 76.34; H, 5.49; N, 8.48%.
Found: C, 76.26; H, 5.61; N, 8.39%.
6
5
6
4
21 18 2 2
+
for C H N O (417.50), Calcd: C, 80.55; H, 5.55; N,
2
8
23
3
1
0.06%. Found: C, 80.25; H, 5.46; N, 10.28%.
-(1H-Benzo[d]imidazol-2-yl)-4-(4-chlorophenyl)-
3
5.1.8 | General procedure for the
synthesis of 6,7-dihydrobenzo[b]thiophen-5
(4H)-ylidene derivatives, 18a–b
2
-phenyl-4,6,7,8-tetrahydroquinolin-5(1H)-one
(16b).
ꢀ
Pale yellow, yield 68%, Mp 205-208 C. IR (KBr) ν max
−
1
(
cm ): 3423-3380 (2NH) 3087, 3054 (CH-aromatic),
1
2
930 (CH-aliphatic), 1666 (CO), 1517 (CC). H NMR
Each elemental sulfur and either malononitrile (0.66 g,
0.01 mol) or ethyl cyanoacetate (1.07 g, 0.01 mol) were
added to a solution of compound 17 (3.30 g, 0.01 mol), in
1,4-dioxane (40 mL) containing triethylamine (0.50 mL).
The reaction mixture was heated under reflux for 3 hours
and then poured onto ice/water mixture, and the partici-
pated product was collected by filtration.
(
DMSO-d , 300 MHz): δ2.23-2.58 (m, 6H, 3CH ), 4.53 (s,
6
2
1
1
1
1
1
H, CH-pyridine), 7.21-7.54 (m, 13H, 2C H , C H ), 9.48,
0.04 (2s, 2H, 2NH). C NMR (DMSO-d , 75 MHz): δ
8.5, 36.2, 39.7 (3CH ), 48.6, 120.5, 121.6, 122.8, 123.4,
23.8, 124.3, 124.6, 125.3, 125.6, 126.2, 126.1, 128.3, 139.5,
40.5, 140.6, 141.3, 142.6, 143.6 (C H , 2C H , imidazole,
6 4 6 5
13
6
2
6
5
6
4
+
pyridine C), 164.4 (CO), 167.5 (CN). EIMS: m/z 451 [M]
5-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile
(28). Anal. for C H ClN O (451.95): Calcd: C, 74.41; H,
28 22 3
ꢀ
4
.91; N, 9.30%. Found: C, 74.31; H, 4.91; N, 9.47%.
-(1H-Benzo[d]imidazol-2-yl)-4-(4-methoxyphenyl)-
(18a). Pale yellow, yield 65%, Mp 150-152 C. IR (KBr) ν
−
1
3
max (cm ): 3462-3353 (NH , NH), 3087, 3054 (CH-aro-
2
2
-phenyl-4,6,7,8-tetrahydroquinoline-5(1H)-one
(16c).
matic), 2930 (CH-aliphatic), 2227 (CN), 1686 (CO), 1540
ꢀ
1
Pale yellow, yield: 72%, Mp 200-204 C. IR (KBr) ν max
(CC). H NMR (DMSO-d , 300 MHz): δ2.21-2.59 (m, 6H,
6
−1
(cm ): 3474-3348 (2NH), 3083, 3054 (CH-aromatic), 2932
3CH ), 4.84 (s, 2H, NH ), 7.23-7.46 (m, 9H, C H , C H ),
2
2
6
4
6 5
1
13
(CH-aliphatic), 1680 (CO), 1517 (CC). H NMR (DMSO-d ,
9.46 (s, 1H, NH). C NMR (DMSO-d , 75 MHz): δ 18.2,
6
6
3
4
1
3
1
1
00 MHz): δ2.22-2.53 (m, 6H, 3CH ), 3.67 (s, 3H, OCH ),
36.2, 39.9 (3CH ), 99.2, 111.0 (CC), 116.8 (CN), 120.5, 121.6,
2
3
2
.58 (s, 1H, CH-pyridine), 7.25-7.53 (m, 13H, 2C H , C H ),
122.8, 123.8, 124.3, 125.3, 125.6, 126.1, 139.9, 140.5, 141.3,
142.6 (C H , C H , thiophene C), 164.8 (CO), 168.3 (CN).
6
4
6 5
13
0.13 (s, 1H, NH). C NMR (DMSO-d , 75 MHz): δ 18.2,
6
6
5
6 4
+
6.6, 39.8 (3CH ), 49.2, 120.8, 121.4, 122.5, 123.7, 123.9,
EIMS: m/z 410 [M] (32). Anal. for C H N OS (410.49):
24 18 4
2
24.5, 124.3, 125.4, 126.8, 126.8, 127.3, 128.1, 139.5, 140.8,
41.6, 142.3, 142.8, 143.9 (C H , 2C H , imidazole, pyridine
Calcd: C, 70.42; H, 4.42; N, 13.65; S, 7.81%. Found: C,
70.05; H, 4.60; N, 13.76; S, 7.92%.
6
5
6 4
+
C), 164.3 (CO), 167.7 (CN). EIMS: m/z 448 [M] (40). Anal.
for C H N O (447.53): Calcd: C, 77.83; H, 5.63; N, 9.39%.
Found: C, 77.61; H, 5.55; N, 9.45%.
Ethyl 5-(1-(1H-benzo[d]imidazol-2-yl)-2-oxo-2-phenyl-
ethyldiene)-2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-
3-carboxylate (18b). Reddish brown yellow, yield 65%, Mp
29 25 3 2
ꢀ
−1
1
50-152 C. IR (KBr) ν max (cm ): 3482-3337 (NH , NH),
2
3
087, 3054 (CH-aromatic), 2930 (CH-aliphatic), 1705,
1
5
.1.7 | Synthesis of 3-(1-(1H-benzo[d]
1686 (2CO), 1540 (CC). H NMR (DMSO-d , 300 MHz):
6
imidazol-2-yl)-2-oxo-2-phenylethylidene)-
cyclohexanone (17)
δ1.12 (t, 3H, J = 6.4 Hz, OCH CH ), 2.21-2.46 (m, 6H,
2
3
3CH ), 4.21 (q, 2H, J = 6.4 Hz, OCH CH ), 4.86 (s, 2H,
2
2
3
1
3
NH ), 7.23-7.46 (m, 9H, C H , C H ), 9.46 (s, 1H, NH).
C
2
6
4
6
5
Equimolar amounts of compound, 12 (2.36 g, 0.01 mol),
NMR (DMSO-d , 75 MHz): δ 16.2 (OCH CH ), 18.3, 36.2,
6
2
3
and cyclohexan-1,3-dione (1.12 g, 0.01 mol) were heated
at 120 C in dry conditions, in an oil bath, for 10 minutes,
39.6 (3CH ), 52.8 (OCH CH ), 97.5, 110.9 (CC), 120.3,
2 2 3
ꢀ
121.2, 122.6, 123.4, 124.6, 125.8, 125.6, 126.3, 139.9, 140.3,
141.1, 142.8 (C H , C H , thiophene C), 165.5, 168.3
and then the reaction mixture was left to cool. The
formed solid product was triturated with diethylether
and then collected by filtration.
6
5
6
4
+
(2CO), 168.8 (CN). EIMS: m/z 457 [M] (40). Anal. for
C H N O S (457.57): Calcd: C, 68.25; H, 5.07; N, 9.18; S,
26 23 3 3
ꢀ
Pale yellow, yield: 78%, Mp 196-198 C. IR (KBr) ν
7.01%. Found: C, 68.36; H, 5.19; N, 9.06; S, 7.12%.
−
1
max (cm ): 3486 (NH), 3080, 3054 (CH-aromatic), 2932
1
(
CH-aliphatic), 1705, 1680 (2CO), 1620 (CC). H NMR
(
2
DMSO-d , 300 MHz): δ2.20-2.58 (m, 6H, 3CH ), 2.80 (s,
5.1.9 | General procedure for
the synthesis of 5,6,7,8-tetrahydro-4H-
chromenes, 19a–c
6
2
H, CH ), 7.22-7.50 (m, 9H, C H , C H ), 8.23 (s, 1H,
2 6 4 6 5
13
NH). C NMR (DMSO-d 75 MHz): δ 19.9, 38.4, 40.5,
4
6
3.2 (4CH ), 97.2, 110.4 (CC), 120.3, 121.8, 123.7, 123.6,
2
1
24.2, 125.3, 126.6, 127.5 (C H , C H ), 164.8, 166.3
Either benzaldehyde (1.08 g, 0.01 mol), p-chlorobenzaldehyde
(1.40 g, 0.01 mol) or p-methoxybenzaldehyde (1.36, 0.01 mol)
6
5
6
4
+
(2CO), 170.3 (CN). EIMS: m/z 330 [M] (36). Anal. for

AZZAM ET AL.
17
and malononitrile (0.66 g, 0.01 mol) were added to a solution
of compound, 17 (3.30 g, 0.01 mol), in 1,4-dioxane (40 mL)
containing triethylamine (0.50 mL). The reaction mixture was
heated under reflux for 3 hours and then poured onto
ice/water mixture, and the participated product was collected
by filtration.
5.1.10 | General procedure for the synthesis
of 1,4,5,6,7,8-hexahydroquinoline, 20a–c
Each of either benzaldehyde (1.08 g, 0.01 mol),
p-chlorobenzaldehyde
(1.40 g,
0.01 mol)
or
p-methoxybenzaldehyde (1.36, 0.01 mol) and malononitrile
(0.66 g, 0.01 mol) were added to a solution of compound
17 (3.30 g, 0.01 mol) in 1,4-dioxane (40 mL) containing
ammonium acetate (1.50 g, 0.02 mol). The reaction mix-
ture was heated under reflux for 3 hours and then poured
onto ice/water mixture, and the participated product was
collected by filtration.
7-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
2
-amino-4-phenyl-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile
ꢀ
(19a). Pale brown, yield: 72%, Mp 123-125 C. R (KBr) ν max
−1
(cm ): 3457-3325 (NH, NH ), 3055 (CH-aromatic), 2962 (CH-
2
1
aliphatic), 2221 (CN), 1688 (CO), 1628 (CC). H-NMR
DMSO-d , 300 MHz): δ2.23-2.29 (m, 6H, 3CH ), 4.61 (s, 1H,
(
6
2
CH-pyran), 4.52 (s, 2H, NH ), 7.18-7.55 (m, 14H, 2C H ,
7-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
2-amino-4-phenyl-1,4,5,6,7,8-hexahydroquinoline-3-carbonitrile
2
6 5
13
C H ), 10.55 (s, 1H, NH). C NMR (DMSO-d , 75MHz): δ
6
4
6
ꢀ
1
1
1
8.1, 36.7, 39.7 (3CH ), 98.0, 112.1 (CC), 50.2, 119.3,
21.5, 122.0, 122.6, 123.6, 124.1, 124.7, 125.2, 126.3,
26.8, 127.1, 128.0, 139.8, 140.2, 140.8, 142.4, 142.6, 142.8
(20a). Pale yellow, yield: 62%, Mp 146-148 C. IR (KBr) ν max
2
−
1
(cm ): 3479-3336 (NH, NH ), 3055 (CH-aromatic), 2962
2
1
(CH-aliphatic), 2220 (CN), 1702 (CO), 1628 (CC). H-NMR
(
(
(
2C H , C H , imidazole, pyran C), 164.6 (CO), 167.7
(DMSO-d , 300 MHz): δ2.21-2.29 (m, 6H, 3CH ), 4.63 (s, 1H,
6
5
6
4
6
2
+
CN). EIMS: m/z 484 [M] (46). Anal. for C H N O
CH-pyridine), 4.58 (s, 2H, NH ), 7.18-7.59 (m, 14H, 2C H ,
3
1
24
4
2
2 6 5
13
484.55): Calcd: C, 76.84; H, 4.99; N, 11.56%. Found: C,
6.61; H, 4.73; N, 11.42%.
-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
-amino-4-(4-chlorophenyl)-5,6,7,8-tetrahydro-4H-chromene-
C H ), 11.06 (s, 1H, NH). C NMR (DMSO-d , 75 MHz): δ
6
4
6
7
18.6, 36.5, 39.4 (3CH ), 97.0, 110.5 (CC), 49.3, 120.6, 121.8,
2
7
122.8, 122.9, 123.4, 124.6, 124.9, 125.0, 126.8, 126.3, 127.5,
128.6, 138.3, 140.6, 141.5, 142.8, 142.9, 143.8 (2C H ,
2
3
6
5
ꢀ
-carbonitrile (19b). Pale brown, yield: 66%, Mp 145-148 C.
C H , imidazole, pyridine C), 165.8 (CO), 168.3 (CN).
6 4
−1
+
IR (KBr) ν max (cm ): 3457-3325 (NH, NH ), 3055 (CH-
EIMS: m/z 482 [M] (40). Anal. for C H N O (483.56):
31 25 5
2
aromatic), 2962 (CH-aliphatic), 2223 (CN), 1688 (CO), 1628
Calcd: C, 77.00; H, 5.21; N, 14.48%. Found: C, 76.77; H,
5.05; N, 14.25%.
1
(
CC). H-NMR (DMSO-d , 300 MHz): δ2.21-2.28 (m, 6H,
6
3
CH ), 4.64 (s, 1H, CH-pyran), 4.50 (s, 2H, NH ), 7.18-7.55
7-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
2-amino-4-(4-chlorophenyl)-1,4,5,6,7,8-hexahydroquinoline-
3-carbonitrile (20b). Pale yellow, yield: 64%, Mp 128-
2
2
13
(m, 13H, C H , 2C H ), 10.58 (s, 1H, NH). C NMR
6 5 6 4
(DMSO-d , 75 MHz): δ 18.1, 36.7, 39.7 (3CH ), 97.6, 111.3
6
2
ꢀ
−1
(
1
1
CC), 51.3, 120.6, 121.1, 122.3, 123.2, 123.8, 124.3, 124.9,
25.6, 126.1, 126.6, 127.3, 128.2, 139.6, 140.7, 140.5, 142.1,
42.9, 143.2 (C H , 2C H , imidazole, pyran C), 164.8 (CO),
131 C. IR (KBr) ν max (cm ): 3473-3339 (NH, NH ),
2
3055 (CH-aromatic), 2962 (CH-aliphatic), 2220 (CN),
1
1702 (CO), 1624 (CC). H-NMR (DMSO-d , 300 MHz):
6
5
6
4
6
+
167.9 (CN). EIMS: m/z 518 [M] (26). Anal. for
δ2.24-2.50 (m, 6H, 3CH ), 4.64 (s, 1H, CH-pyridine),
2
C H ClN O (518.99): Calcd: C, 71.74; H, 4.47; N, 10.80%.
4.50 (s, 2H, NH ), 7.22-7.55 (m, 13H, C H , 2C H ),
31
23
4
2
2
6
5
6
4
13
Found: C, 71.85; H, 4.26; N, 10.47%.
-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
-amino-4-(4-methoxyphenyl)-5,6,7,8-tetrahydro-4H-chromene-
-carbonitrile (19c). Pale brown, yield: 66%, Mp 145-
10.58 (s, 1H, NH). C NMR (DMSO-d 75 MHz): δ 18.2,
6
7
36.8, 39.5 (3CH ), 97.5, 111.2 (CC), 49.9, 120.8, 122.2, 122.6,
2
2
123.7, 123.2, 124.1, 124.5, 125.3, 126.0, 126.8, 127.5, 128.3,
139.4, 140.3, 140.6, 142.6, 142.3, 143.8 (C H , 2C H ,
3
1
3
1
6
5
6
4
ꢀ
−1
48 C. IR (KBr) ν max (cm ): 3457-3325 (NH, NH ),
imidazole, pyridine C), 165.3 (CO), 167.5 (CN). EIMS:
2
+
055 (CH-aromatic), 2962 (CH-aliphatic), 2219 (CN),
688 (CO), 1628 (CC). H-NMR (DMSO-d , 300 MHz):
m/z 518 [M] (36). Anal. for C H ClN O (518.01):
3
1
24
5
1
Calcd: C, 71.88; H, 4.67; N, 13.52%. Found: C, 71.61; H,
4.98; N, 13.58%.
6
δ2.21-2.28 (m, 6H, 3CH ), 3.67 (s, 3H, OCH ), 4.64 (s, 1H,
2
3
CH-pyran), 4.50 (s, 2H, NH ), 7.18-7.55 (m, 13H, C H ,
7-(1-(1H-Benzo[d]imidazol-2-yl)-2-oxo-2-phenylethyldiene)-
2-amino-4-(4-methoxyphenyl)-1,4,5,6,7,8-hexahydroquinoline-
2
6
5
1
3
2
C H ), 10.58 (s, 1H, NH). C NMR (DMSO-d 75 MHz):
6 4 6,
ꢀ
δ 18.1, 36.7, 39.7 (3CH ), 50.4 (OCH ), 97.1, 110.8 (CC),
3-carbonitrile (20c). Yellow, yield: 66%, Mp 120-123 C.
2
3
−
1
5
1
1
1
2.3, 120.6, 121.1, 122.5, 123.1, 123.8, 124.3, 124.6, 125.6,
26.4, 126.6, 127.3, 128.2, 139.6, 140.3, 140.6, 142.1, 142.3,
42.8 (C H , 2C H , imidazole, pyran C), 164.5 (CO),
IR (KBr) ν max (cm ): 3467-3310 (NH, NH ), 3055 (CH-
2
aromatic), 2962 (CH-aliphatic), 2219 (CN), 1703 (CO),
1
1568 (CC). H-NMR (DMSO-d , 300 MHz): δ2.28-2.51 (m,
6
5
6
4
6
+
67.6 (CN). EIMS: m/z 514 [M] (38). Anal. for
6H, 3CH ), 3.56 (s, 3H, OCH ), 5.51 (s, 1H, CH-pyridine),
2
3
C H N O (514.57): Calcd: C, 74.69; H, 5.09; N, 10.98%.
Found: C, 74.78; H, 4.94; N, 10.76%.
4.59 (s, 2H, NH ), 7.21-7.59 (m, 13H, C H , 2C H ), 10.58
2 6 5 6 4
32
26
4
3
1
3
(s, 1H, NH). C NMR (DMSO-d 75 MHz): δ 18.3, 36.7,
6

18
AZZAM ET AL.
1
3
1
1
9.5 (3CH ), 50.8 (OCH ), 98.0, 111.6 (CC), 50.6, 120.6,
21.9, 122.2, 123.8, 123.6, 124.00, 124.3, 125.6, 126.4,
26.8, 127.3, 128.2, 139.6, 140.3, 140.8, 142.0, 142.6, 143.2
2219 (CN), 1703 (CO), 1568 (CC). H-NMR (DMSO-d ,
2
3
6
300 MHz): δ2.28-2.51 (m, 4H, 2CH ), 3.62 (s, 3H, OCH ),
5.54 (s, 1H, CH-pyridine), 4.88, 5.16 (2s, 4H, 2NH ),
7.24-7.53 (m, 4H, C H ), 10.22 (s, 1H, NH). C NMR
6 4
(DMSO-d , 75 MHz): δ 36.2, 39.5 (2CH ), 50.8 (OCH ),
116.8, 117.1 (2CN), 50.8, 120.5, 122.6, 126.4, 127.1,
132.6, 133.3, 134.7, 136.1, 139.3, 140.5, 142.7, 143.9
C H , thiophene, pyran C). EIMS: m/z 376 [M] (24).
2
3
2
1
3
(
(
(
C H , 2C H , imidazole, pyridine C), 164.5 (CO), 167.6
CN). EIMS: m/z 513 [M] (28). Anal. for C H N O
513.01): Calcd: C, 74.83; H, 5.30; N, 13.64%. Found: C,
4.64; H, 5.24; N, 13.79%.
6
5
6
4
+
3
2
27
5
2
6
2
3
7
+
(
6
4
Anal. for C H N O S (376.43): Calcd: C, 63.81; H,
2
0
16
4 2
5
.1.11 | General procedure for the
4.28; N, 14.88; S, 8.52%. Found: C, 63.48; H, 4.00; N,
14.61; S, 8.68%.
synthesis of 5,6-dihydro-4H-thieno[3,2-h]
chromene derivatives, 22a–c
ORCID
To a solution of compound, 21 (1.92 g, 0.01 mol), in
Rasha A. Azzam https://orcid.org/0000-0002-6807-2110
Rafat M. Mohareb https://orcid.org/0000-0003-3922-
1
,4-dioxane (40 mL), containing triethylamine (0.50 mL),
each of either benzaldehyde (1.08 g, 0.01 mol), p-
chlorobenzaldehyde (1.40 g, 0.01 mol) or p-methoxybenzal-
dehyde (1.36 g, 0.01 mol), and malononitrile (0.66 g,
8
03X
REFERENCES
0
.01 mol) were added. The reaction mixture was heated
[
1] P. Eilbracht, L. Barfacker, C. Buss, C. Hollmann, E. Kitsos-
Rzychon, L. Kranemann, T. Rische, R. Roggenbuck,
A. Schimdt, Chem. Rev. 1999, 99, 3329.
under reflux for 3 hours and then poured onto ice/water
mixture, and the participated product was collected by
filtration.
[2] U. Bora, A. Saikia, R. C. Boruah, Org. Lett. 2003, 5, 435.
[
[
3] L. Weber, Drug Discov Today 2002, 7, 143.
4] C. Hulme, V. Gore, Curr. Med. Chem. 2003, 10, 51.
2
,8-Diamino-4-phenyl-5,6-dihydro-4H-thione[3,2-h]
chromene-3,7-dicarbonitril (22a). Pale brown, yield 72%,
Mp 98-101 C. IR (KBr) ν max (cm ): 3458-3349 (NH ),
060 (CH-aromatic), 2940 (CH-aliphatic), 2221 (CN), 1688
CO), 1580 (CC). H NMR (DMSO-d , 300 MHz): δ2.13-
ꢀ
−1
[5] P. A. Tempest, Curr Opin Drug Discov Devel 2005, 8, 776.
2
[
6] N. Elders, D. van der Born, L. J. D. Hendrickx, B. J. J. Timmer,
A. Krause, E. Janssen, F. J. J. de Kanter, E. Ruijter,
R. V. A. Orru, Angew. Chem. Int. Ed. Engl. 2009, 48, 5856.
3
(
1
6
2
.39(m, 4H, 2CH ), 4.90, 5.13 (2s, 4H, 2NH ), 5.98 (s, 1H,
2 2
[7] G. V. M. Sharma, K. L. Reddy, P. S. Lakshmi, P. R. Krishna,
Synthesis 2006, 1, 55.
13
CH-pyran), 7.18-7.46 (m, 5H, C H ). C NMR (DMSO-d6,
6
5
7
1
1
3
6
3
5 MHz): δ23.6, 39.9 (2CH ), 116.3, 117.0 (2CN), 49.8,
24.9, 126.1, 127.5, 128.1, 132.6, 133.8, 135.0, 136.3, 139.7,
[8] G. Maga, S. Gemma, C. Fattorusso, G. A. Locatelli, M. Persico,
G. Campiani, Biochemistry 2005, 44, 9637.
2
[9] M. A. Naylor, M. A. Stephen, J. Nolan, Anticancer Drug Design
39.5, 141.8, 143.6 (C H , thiophene, pyran C). EIMS: m/z
6
5
+
1993, 8, 439.
46 [M] (32%); Anal. for C H N OS (346.41): Calcd: C,
19 14 4
[
10] S. Wagle, A. V. Adhikari, N. S. Kumari, Ind. J. Chem. 2008,
7, 439.
5.88; H, 4.07; N, 16.17; S, 9.26%. Found: C, 65.51; H,
.88; N, 16.30; S, 9.11%.
4
[
11] L. S. Postnikov, I. V. Korovina, A. D. Kagarlitskii,
2,8-Diamino-4-(4-chlorophenyl)-5,6-dihydro-4H-thione[3,
L. A. Krichevskii, Russ. J. Appl. Chem. 2008, 81, 320.
2
-h]chromene-3,7-dicarbonitrile (22b). Orange, yield 74%,
[12] J. Guillon, M. Borgne, C. Rimbault, S. Moreau, S.
Savrimoutou, N. Pinaud, S. Baratin, M. Marchivie, S. Roche,
A. Bollacke, A. Pecci, L. Alevrez, V. Desplat, J. Jose, Eur. J.
Med Chem, 2013, 65, 205.
ꢀ
−1
Mp 108-110 C. IR (KBr) ν max (cm ): 3493-3325 (NH ),
2
3060 (CH-aromatic), 2940 (CH-aliphatic), 2223, 2192 (2CN),
1
1688 (CO), 1580 (CC). H NMR (DMSO-d , 300 MHz):
6
[13] S. Kirkiacharian, D. T. Thuy, S. Sicsic, R. Bakhchinian,
R. Kurkjian, T. Tonnaire, Farmaco II 2002, 57, 703.
δ2.13-2.39 (m, 4H, 2CH ), 4.90, 5.13 (2s, 4H, 2NH ), 5.98 (s,
2
2
13
1H, CH-pyran), 7.18-7.46 (m,4H, C H ). C NMR (DMSO-
6 4
[14] J. Guillon, P. Dallemagne, B. Pfeiffer, P. Renard, D. Manechez,
A. Kervran, S. Rault, Eur. J. Med. Chem. 1998, 33, 293.
d , 75 MHz): δ 32.6, 39.9 (2CH ), 116.3, 116.9 (2CN), 50.0,
6
2
1
1
3
5
3
21.2, 123.2, 126.9, 127.5, 132.3, 133.3, 134.3, 136.3, 139.7,
[15] R. A. Glennon, M. K. Daoud, M. Dukat, H. Syed, Bioorg. Med.
Chem. 2003, 11, 4449.
40.3, 142.3, 143.3 (C H , thiophene, pyran C). EIMS: m/z
6
4
+
[
[
[
[
16] R. M. Mohareb, N. Y. Abdo, K. A. EL-Sharkawy, Anti-Cancer
Agents Med. Chem. 2018, 18, 1736.
17] R. M. Mohareb, E. M. Samir, P. A. Halim, Bioorg. Chem. 2019,
80 [M] (32%); Anal. for C H ClN OS (380.85): Calcd: C,
19
13
4
9.92; H, 3.44; N, 14.71; S, 8.42%. Found: C, 60.15; H,
.60; N, 14.93; S, 8.61%.
83, 402.
2
,8-Diamino-4-(4-methoxyphenyl)-5,6-dihydro-4H-
18] R. M. Mohareb, K. A. El-Sharkawy, F. O. El-Farouk, Med.
Chem. Res. 2019, 28, 1885.
19] B. P. McKibben, C. H. Cartwright, A. L. Castelhano, Tetrahe-
dron Lett. 1999, 40, 5471.
thione[3,2-h]chromene-3,7-dicarbonitrile (22c). Yellow,
ꢀ
−1
yield: 66%, Mp 120-123 C. IR (KBr) ν max (cm ):
467-3310 (NH), 3055 (CH-aromatic), 2962 (CH-aliphatic),
3

AZZAM ET AL.
19
[
[
[
[
20] K. Wang, D. Kim, A. Dömling, J. Comb. Chem. 2010,
2, 111.
21] R. Mishra, K. K. Jha, S. Kumar, I. Tomer, Der Pharma Chem.
011, 3, 38.
22] N. S. Shetty, R. S. Lamani, I. A. M. Khazi, J. Chem. Sci. 2009,
21, 30.
1
How to cite this article: Azzam RA,
Mohareb RM, Helal MH, Eisa KK. Cytotoxicity,
tyrosine kinase inhibition of novel pyran, pyridine,
thiophene, and imidazole derivatives. J Heterocyclic
Chem. 2020;1–19. https://doi.org/10.1002/jhet.4010
2
1
23] M. McTigue, B. W. Murray, J. H. Chen, Y. L. Deng, J. Solowiej,
R. S. Kania, Proc. Natl. Acad. Sci. USA 2012, 109, 18281.