Rational design and synthesis of novel 2-(substituted-2H-chromen-3-yl)-5-aryl-1H-imidazole derivatives as an anti-angiogenesis and anti-cancer agent

Article abstract of DOI:10.1039/c4ra09945a

Based on earlier proven pharmacophore analogues of cancer a novel 2-(substituted-2H-chromen-3-yl)-5-aryl-1H-imidazoles (13-16) were rationally designed and synthesized by the reaction of chromene-3-carboxylic acids (10a-d) with substituted acyl bromides in the presence of TEA followed by refluxing with NH₄OAc in toluene. Compounds 13-16 were screened in vitro for the inhibition of KRAS/Wnt and their anti-angiogenesis properties. Compound 16f has been identified as a potent anti-angiogenesis molecule, which can be considered as a new lead structure. The molecular docking analysis displayed the higher binding affinity of 16f with KRAS, Wnt and VEGF.

Full text of DOI:10.1039/c4ra09945a

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Page 1 of 43
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DOI: 10.1039/C4RA09945A
Rational design, synthesis of novel 2-(substituted 2H-chromen-3-yl)-5-aryl-
H-imidazole derivatives as an anti-angiogenesis and anti-cancer
1
1
2
3
4
Gopinath Gudipudi , Sagurthi Someswar. R , Shyam Perugu , G. Achaiah and David
1
Krupadanam. G. L *.
1
Department of Chemistry, Osmania University, Hyderabad, India 500 007
2
Department of Genetics, Osmania University, Hyderabad, India 500 007
3
Department of Biochemistry, Osmania University, Hyderabad, India 500 007
4
Medicinal Chemistry Division, University College of Pharmaceutical Sciences
Kakatiya University, Warangal, India - 506 009
*Corresponding author.
Prof. G. L. David Krupadanam,
Department of Chemistry,
Osmania University, Hyderabad – 500 007, INDIA
E-mail: gldkrupa@gmail.com
Tel: 00-91-9849128145.

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Abstract:
Based on earlier proven pharmacophore analogues of cancer a novel 2ꢀ(substituted 2Hꢀ
chromenꢀ3ꢀyl)ꢀ5ꢀarylꢀ1Hꢀimidazoles (13-16) were rationally designed and synthesized. By
the reaction of chromeneꢀ3ꢀcarboxylic acids (10a-d) with substituted acyl bromides in the
4
presence of TEA followed by refluxing with NH OAc in toluene. The compounds 13-16 were
screened in vitro for inhibition of KRAS/Wnt and their antiꢀangiogenesis property.
Compound 16f has been identified as a potent antiꢀangiogenesis molecule which can be
considered as a new lead structure. Molecular docking analysis displayed higher binding
affinity of 16f with KRAS, Wnt and VEGF.
Keywords: Chromeneꢀ3ꢀcarboxylic acid, Imidazole, Antiꢀcancer activity, Antiꢀangiogenesis
activity, Molecular docking analysis.

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1.0 Introduction:
Several researchers are working to discover new drugs based on natural products to treat
cancer but the success rate is very less due to toxicity issues as well as due to the inability of
the compounds to act selectively on the cancer cell. Epidemiological studies have reported
that diets rich in isoflavones particularly Soybeans and Soya products reduce the incidence of
various cancers. In vitro and in vivo animal studies showed that isoflavones genistein (1) and
1
ꢀ8
diadzein (2) are promising agents for cancer chemoprevention and inhibition of tumor
progression. Isoflavones inhibit cell growth at concentrations greater than 20 µM. Inhibition
of cell proliferation by isoflavones may involve interference with signaling via the epidermal
growth factor receptor kinase, effects on cell cycle, capsase or transforming growth factor β
signaling.
9
ꢀ12
Tumor angiogenesis is a complex dynamic process necessary for the growth of all tumors.
Tumor cannot grow through a defined volume if it is not vascularized. Among the angiogenic
factors secreted by the tumor cells, the Vascular Endothelial Growth Factor (VEGF) is one of
the important. Most human cancer cells express elevated levels of VEGF and VEGF
receptors on their surface. An antiꢀangiogenic drug impairs VEGF pathway and tumor
13
vasculature by targeting VEGF (for eg: Bevacizumab a monoclonal antibody) or their
receptors. In the last two decades several small molecules are being evaluated as antiꢀ
14
angiogenicagents. A few successfully derived natural product anticancer drugs include
15,16
17
vincristine (acute lymphocytic leukemia),
taxol (ovarian cancer) and etoposide (lung
18
cancer).
l9ꢀ23
Synthetic analogs of the isoflavones, diadzein (2) and phenoxodiol (3)
showed strong
apoptotic and antiꢀangiogenic activities in ovarian carcinoma in vitro and reduced tumor
volume of ovarian xenograftsin vivo. Phenoxodiol (3) is a dihydroxylatedꢀ3ꢀarylchromene.

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Synthetic heterocyclic compounds containing nitrogen and oxygen are commonly explored as
4
anticancer agents with antiꢀangiogenesis as the mode of action. These compounds are
chromenes with an aryl imidazole substitution at 3ꢀposition of chromene. The imidazole
moiety is present in a wide range of naturally occurring compounds. It is a common scaffold
in many significant biomolecules, including biotin, histamine, the essential amino acid
2
4
histidine, and the pilocarpine alkaloids. The use of imidazole and their derivatives in
chemical processes, especially in pharmaceuticals have increased, because of their ability to
2
5
form hydrogen bond with the active site of several enzymes. The incorporation of the
imidazole nucleus is an important synthetic strategy in rational drug discovery.
We rationally designed and synthesized novel 2ꢀ(substituted 2Hꢀchromenꢀ3ꢀyl)ꢀ5ꢀarylꢀ
1
Hꢀimidazoles (13a-j; 14a, e-j; 15a, e-j; 16a-f) that are structurally similar to the natural
isoflavones and phenoxodiol and are considered potential antiꢀangiogenic agents. Molecular
models enable us to build the three dimensional shape of small molecules and target. It allows
us to check whether the shape of a potential lead is complementary to the shape of its target.
It also allows us to calculate binding energy liberated when a molecule binds to active site.
Molecular modelling has reduced need to synthesize every analogue of a lead compound. The
synthesized compounds were characterized by the IR, NMR, Mass Spectrometric methods.
Of those synthesized compounds, fourteen compounds were screened in the Eli Lilly’s Open
Innovation Drug Discovery programme (OIDD). Therefore, this leads used competitive
biological activity against cancer cell lines. Experimental procedures for angiogenesis assay,
cellular imaging and Endothelial and nuclear staining were carried out.

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2
2
1
.0 Results and discussion
.1 Chemistry:
,3ꢀDimethoxybenzene (5) on regioselective lithiation with nꢀBuLi at 0 °C in THF/TMEDA
gave 2ꢀlithiated dimethoxybenzene which on treatment with DMF gave 2,6ꢀ
2
6
dimethoxybenzaldehyde (6) , Selective mono demethylation with AlCl gave 2-hydroxyꢀ6ꢀ
3
2
6,27
methoxybenzaldehyde (8a).
resorcinol by VilsmeierꢀHaackformylation.
b (Schemeꢀ1). 3ꢀMethoxysalicylaldehyde (vanillin) and salicylaldehydes are commercially
available. Treatment of the substituted salicylaldehydes (8a-d), with acrylonitrile and 1,4ꢀ
2,4ꢀDihydroxybenzaldehyde (7) was prepared from
28, 29
3
Compoundꢀ7 on methylation with CH I gave
8
3
0
diazabicyclo [2.2.2] octane (DABCO) as a catalyst in BaylisꢀHillman reaction afforded
31
chromeneꢀ3ꢀnitriles (9a-d), which in turn were hydrolyzed to chromeneꢀ3ꢀcarboxylic acids
10a-d) (Schemeꢀ2). Chromeneꢀ3ꢀcarboxylic acids (10a-d) were reacted with substituted acyl
bromides (12a-j) (Schemeꢀ3) in the presence of TEA followed by refluxing with NH OAc in
toluene gave 2ꢀ(substitutedꢀ2Hꢀchromenꢀ3ꢀyl)ꢀ5ꢀarylꢀ1Hꢀimidazoles (13-16) (Schemeꢀ4, 5,
(
4
3
1
6, & 7).
2.2 Biological activity
2.2.1 Anti-Cancer activity
Of the 29 chromenyl imidazoles synthesized in this study 14 compounds (16a-f, 15h, 14f, h,
j, 13f, g, i, j) were selected for screening from OIDD chemo informatics filter. Compounds
(16a-f, 15h, 14f, h, j, 13f, g, i, j) were subjected to in vitro primary screening in the KRASꢀ
Wnt SL (Synthetic Lethal) in the basal viability of colon cancer cell lines (SW480, DLDꢀ1,
HCT116, GSK 3b in pretreated viability HCT116, HTꢀ29, RKO, SW837, Colo320, SNUꢀ
C1) and the % inhibition (at 0.2, 2.0 and 20 µM) was calculated by IC values (summarized
5
0
in Tableꢀ1). According to the IC50 values from their concentrationꢀresponse curves

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compounds 13g, 16a, 16e and 16f were found to be the potent inhibitors. Especially
compound 16f showed IC50 value in the range of 0.37ꢀ8.3 µM on the different cancer cell
lines tested. The colorectal cancer cell line inhibitions depend on the nature of substituents on
phenyl ring of imidazole nucleus and methoxy group of chromene nucleus. IC values were
5
0
also determined for other three compounds in the basal TCF/TK Luciferase DLDꢀ1 assay
wherein 16f showed IC50 = 4.731 µM (Table 2). It was observed that compounds
th
possessingmethoxy group on 5 position of chromenenucleus demonstrated augmented
cancer inhibitory activity, benzyloxy substitution was found more favorable towards cancer
inhibition over other substitution.
2.2.2 Anti-angiogenic activity
The three compounds (16a, 16e, 16f) were screened for antiꢀangiogenesis activity and they
exhibited greater than 50% inhibition of tube area at 10 µM in primary single point assay.
These three were further screened at different concentrations to draw CRC (concentration
response curves) and IC50 values (Tableꢀ3). Only the compound 16f with benzyloxy
th
th
substitution at 4 position of the phenyl ring and methoxy group on 5 position of chromene
nucleus showed significant activity with IC50 of 0.89 µM (Fig.2), and the remaining two
compounds showed IC50 values greater than 10 µM. The compounds lacking the benzyloxy
substituent failed to exhibit significant antiangiogenic activity indicating the importance of
benzyloxy group for binding to the receptor and the subsequent inhibitory activity. Thus, our
studies resulted in a new lead molecule with potent antiꢀangiogenic activity better than the
32
earlier synthesized compounds (isoflavone metabolite 6ꢀmethoxyequol; IC50 value with 3).
Novel 16f compound could be studied further to discover a new clinical and therapeutic
agents useful in cancer chemotherapy.

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Figure 2
2.3 Molecular Docking Studies
2.3.1. Binding of 16f to Human KRAS receptor
The Docking of compound 16f in the binding site of Human KRAS receptor illustrated that
the chromene and imidazole ring play a decisive role in inhibiting angiogenesis activity. The
docking results showed hydrogen bonding interactions between chromene ring oxygen with
i) amine group of Asn 26 with a bond distance 1.1 Å, ii) ND2 of Asn 26d = 2.5 Å and iii) His
2
7 d= 3.2 Å. Methoxy oxygen in the chromene ring also showed hydrogen bonding with His
7, d = 2.8 Å.Further hydrogen bonding interactions were also observed involving the two
2
nitrogen atoms of imidazole ring with backbone carbonyl of Gln 25 (d = 2.6 Å and d = 2.3
Å) and Ile 24 (d = 3.4 Å). Chromene aromatic ring of 16f was surrounded by Asn26, His 27,
Gln 25 and Ile 24 amino acid residues (Figꢀ3&4).
Figure 3 & Figure 4
2.3.2. Binding of 16f to Wnt receptor
Docking of compound 16f in the active site of Human Wnt receptor showed hydrogen
bonding between nitrogen atom of imidazole ring with backbone carbonyl of Gln 25 CB
(d=1.66 Å) and His 27 (d= 3.03 Å). Oxygen atom of chromene ring showed interactions with
amine group of Tyr100 (1.905Å) (Figꢀ5&6).
Figure 5 & Figure 6
.3.3. Binding of 16f to VEGF receptor
2
The 16f in the active site of VEGF receptor showed two hydrogen bonding interacts between
nitrogen atom of imidazole ring with Arg 82 (d= 2.37 Å and d= 2.05 Å). Further hydrogen

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bonding interactionsfrom the oxygen atom of chromene ring and amine group of Arg 105
d=1.93 Å) was observed (Figꢀ7 & 8).
(
Figure 7 & Figure 8
For the other chromenyl imidazoles now synthesized their docking studies did not show
closer interactions with KRAS, Wnt and VEGF receptors.
3.0 Conclusion:
Several new 2ꢀ(substituted 2Hꢀchromenꢀ3ꢀyl)ꢀ5ꢀarylꢀ1Hꢀimidazoles (13-16) were rationally
designed, synthesized and subjected to in vitro primary anticancer screening against several
cancer cell lines (SW480, DLDꢀ1, HCT116, GSK 3b in pretreated viability HCT116, HTꢀ29,
RKO, SW837, Colo320 and SNUꢀC1). Among them four compounds (13g, 16a, 16e and 16f)
were subjected to basal TCF/TK Luciferase DLDꢀ1assay. Results of in vitro cancer assay
indicated that all the compounds showed considerable cancer inhibition. However,
th
th
substitution of methoxy group on 5 position of chromene and 4 position of benzyloxy
group on phenyl ring of imidazole was found to bemore favorable for cancer inhibition.
th
Whereas compounds with no methoxy group at 5 position on chromene showed diminished
cancer activity. Among all the screened compounds, 16f was found to be the morepotent
inhibitor of cancer with the highest selectivity. Further in antiꢀangiogenesis assay compound
16f showed potent activity in inhibiting VGF_ADSC/CFC AngioTube area. Molecular
docking analysis also exhibited higher binding affinity of 16f with Kras, Wnt and VEGF
ligands. Hence 16f could be considered as a lead structure in the development of new series
of antiꢀangiogenesis/anticancer agents.
4.0 Experimental section:

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4.1. General experimental methods:
Unless otherwise specified, all solvents and reagents were obtained from commercial
suppliers. Solvents were purified as per the procedures given in the ‘’Text book of practical
th
organic chemistry’’ by Vogel (6 Edition). All reactions were performed under nitrogen
atmosphere unless otherwise noted. Column chromatography was performed using Merck
1
silica gel 60ꢀ120 mesh. H NMR spectra were recorded on Bruker spectrometer at 400 MHz
13
spectrometer, C NMR spectra were acquired on 100.6 MHz with tetramethylsilane as
internal standard, chemical shift (δ) are reported in ppm. (δ) Shift (multiplicity, coupling
constant, proton count). Mass spectral analysis was accomplished using electro spray
ionization (ESI) techniques.
4.2. Preparation of 1, 3-dimethoxybenzene (5):
To a stirred solution of resorcinol 4 (20 g, 0.18 mol) and acetone (200 ml) in an ice both was
added K CO (62.72 g, 0.45 mol) and methyl iodide (25.8 ml, 0.399 mol) drop wise over a
2
3
period of 10 minutes. After addition, the solution was stirred for overnight at rt. After
completion the reaction acetone was removed under reduced pressure. The crude was diluted
with water and extracted two times with ethyl acetate. The combined ethyl acetate extracts
were dried (Na
2
SO
4
) and evaporated. The residue was purified by chromatography, eluting
1
with ethyl acetate/petꢀetherto give the title compound 5 (22g, 87.69%). H NMR (CDCl
3
) δ:
3
.78 (s, 6H, 2xOCH ), 6.4 (t, J = 2.0 Hz, H ), 6.5 (dd, J = 2.0 Hz, H ), 6.52 (dd, J = 1.6 Hz,
3 5 4
13
H ), 7.2 (t, J = 2.0, H ). C NMR (CDCl ) δ: 56.5 (2xOꢀC), 100.4 (C ), 107.5 (C &C ), 129.8
6
2
3
2
4
6
5 1 3
(C ), 162.7 (C &C ).
4.3. Preparation of 2,6-dimethoxybenzaldehyde (6):

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A suitable RB flask was charged with 1,3ꢀdimethoxybenzene (5) (21.5 g, 0.155 mol), N, N,
N’, N’– tetramethylethylenediamine (TMEDA, 27.6 ml, 0.176 mol) and dry THF (200 ml).
At 0 °C, 1.6 M nꢀbutyl lithium (116.77 ml, 0.186 mol) was added. The solution was stirred at
5
°C for 30 minutes and dry DMF (18.3 ml, 0.233 mol) was added slowly and maintained the
temperature less than 10 °C (38 °C adiabatic temperature rise from the addition). The solution
was continued for stirring for 2 hour and quenched with 4 M HCl under cold water and
continued the stirring for 30 minutes at 5 to 15 °C. The reaction mixture was filtered and
washed with water followed petꢀether successively to get compound 6 as off white solid (18.4
1
g, 71.15 %). H NMR (CDCl ) δ: 3.89 (s, 6H, 2xOCH ), 6.4 (t, J = 2.0 Hz, H ), 6.58 (d, J =
3
3
5
1
3
2
.0 Hz, 2H, H & H ), 7.46 (t, J = 8.8 Hz, H ), 10.51 (s, CHO). C NMR (CDCl ) δ: 56.06
3
5
4
3
(
OꢀC), 103.8 (C
3
&C
5
), 114.3 (C
1
), 135.9 (C
4
2 8
), 162.2 (C &C ), 189.4 (CHO).
4.4. Preparation of 2,4–Dihydroxybenzaldehyde (7):
To a well cooled (0–5 °C) solution of resorcinol (4) (20 g, 0.18 mol) in acetonitrile (200 ml),
dry DMF (21.24 ml, 0.272 mol) and freshly distilled dry POCl (25.34 ml, 0.272 mol) were
3
added with constant stirring at 0–5 °C. The salt that separated was filtered and was washed
with cold acetonitrile. To this salt, water was added and heated at 50 °C for 0.5 h and then
cooled. The solid that separated was filtered, washed with cold water, and dried to give 2,4ꢀ
1
dihydroxybenzaldehyde (7) (18 g, 72%). H NMR (CDCl
3
) δ: 6.38 (d, J = 1.2 Hz, H
3
), 6.5
(
dd, J = 10.4, 2.0 Hz, H ), 7.35 (d, J = 8.8 Hz, H ), 9.64 (s, 2ꢀOH), 10.1 (s, 4ꢀOH), 11.42 (s,
5 6
1
3
3 3 5 1 6 2
CHO). C NMR (CDCl ) δ: 102.8 (C ), 109.2 (C ), 114.5 (C ), 135.8 (C ), 164.3 (C ), 165.8
4
(C ), 194.0 (CHO).
4.5. Preparation of 2-hydroxy-6-methoxybenzaldehyde (8d):
To a RB flask with AlCl
3
(22.02 g, 0.165 mol) and dichloromethane (120 ml) cooled to ꢀ15
°C, solution of 2,6ꢀdimethoxybenzaldehyde (6) (18 g, 0.108 mol) in dichloromethane (60 ml)

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was slowly added while maintaining the temperature below 0 °C. The solution was slowly
warmed to ambient temperature and allowed to stir for 6 hours. A solution of con.HCl in
water was slowly added while maintaining the temperature below 25 °C, the dichloromethane
was removed under vacuum distillation. The product was collected by filtration and washed
with a solution of con.HCl and water. After drying compound 8d was obtained (13 g, 78.9%).
1
H NMR (CDCl
), 11.97 (s, CHO). C NMR (CDCl
), 138.4 (C ), 162.4 (C ), 163.6 (C ), 194.3 (CHO).
3
) δ: 3.89 (s, OCH
3
), 6.37 (d, J = 8.4 Hz, H
3
), 6.53 (d, J = 8.4 Hz, H
5
), 7.42 (t,
),
13
J = 8.4 Hz, H
4
3
) δ: 55.8 (OꢀC), 100.8 (C ), 109.9 (C
5
3
1
10.8 (C
1
4
6
2
4.6. Preparation of 2-hydroxy-4-methoxybenzaldehyde (8c):
To a stirred solution of 7 (18 g, 0.13 mol) and acetone (150 ml) in an ice both was added
CO (35.88 g, 0.26 mol) and methyl iodide (12.18 ml, 0.195 mol) drop wise over a period
K
2
3
of 10 minutes. After addition, the solution was stirred for overnight at rt. After completion the
reaction acetone was evaporated. The crude was diluted with water and extracted two times
with ethyl acetate. The combined ethyl acetate extracts were dried (Na SO ) and evaporated.
2
4
The residue was purified by chromatography, eluting with ethyl acetate/petꢀetherto give the
1
title compound 8c (13 g, 68.4%). H NMR (CDCl
3
) δ: 3.85 (s, OCH
), 9.71 (s, OH), 11.49 (s, CHO). C
), 114.0 (C ), 135.9 (C ), 162.0 (C ), 164.2
3
), 6.42 (d, J = 2.0 Hz,
13
H
3
), 6.54 (dd, J = 8.4, 2.4 Hz, H
NMR (CDCl ) δ: 56.0 (OꢀC), 103.0 (C
), 194.0 (CHO).
5
), 7.42 (d, J = 8.4 Hz, H
6
3
3
), 108.0 (C
5
1
6
2
(C
4
4.7. General procedure for the synthesis of Substituted-2H-chromene-3-carbonitriles
(
9a-d): Substituted salicylaldehydes (1.0 mol) (8a-d) with excess of acrylonitrile in the
presence of 1,4ꢀdiazabicyclo [2.2.2] octane (DABCO, 0.25 mol) as a catalyst was stirred at
0 °C for 10 h, undergo BaylisꢀHillman reaction. The excess acrylonitrile was removed under
reduced pressure, and then the reaction mixture was dissolved in ethyl acetate, washed with
8

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2 4
1N NaOH followed by 1N HCl. The organic phase was dried over anhydrous Na SO , filter
and the solvent was evaporated under vacuum and the residue was subjected to column
chromatography using silica gel (60ꢀ120) to obtain the product substitutedꢀ2Hꢀchromeneꢀ3ꢀ
carbonitriles 9a-d, in quantitative yield.
4.7.1.2H-chromene-3-carbonitrile (9a):
1
Yellow solid, yield 75 %. H NMR (CDCl
3
) δ: 4.8 (d, J = 1.2 Hz, OꢀCH
), 7.09 (dd, J = 7.6, 1.2 Hz, H ), 7.153 (s, H
). C NMR (CDCl ) δ: 71.4 (C ), 109.0 (C ), 114.2 (C ), 115.7 (C4a), 117.3
), 126.5 (C ), 128.4 (C ), 141.8 (C ), 157.5 (C8a).
2
), 6.86 (d, J = 8.0,
H
8
), 6.96 (td, J = 7.6, 0.8 Hz, H
6
5
4
), 7.25 (td, J =
13
8
.0, 0.8 Hz, H
7
3
2
3
8
(
CN), 121.4 (C
6
5
7
4
4.7.2. 8-Methoxy-2H-chromene-3-carbonitrile (9b):
1
Off white solid, yield 70 %. H NMR (CDCl
3
) δ: 3.88 (s, OCH
3
), 4.86 (d, J = 1.2 Hz, OCH
). C NMR (CDCl ) δ: 55.5 (OCH ), 64.4
), 117.0 (CN), 125.2 (C ), 138.7 (C ),
2
),
13
6
.74 (m, H
), 105.4 (C
54.9 (C8a), 162.8 (C
6
), 6.93 (m, 2H, H
), 113.5 (C ), 115.9 (C4a), 118.9 (C
).
4
& H
7
), 7.17 (m, H
5
3
3
(C
2
3
7
5
6
4
1
8
4.7.3. 7-Methoxy-2H-chromene-3-carbonitrile (9c):
1
Off white solid, yield 72 %. H NMR (CDCl
3
) δ: 3.8 (s, OCH
3
), 4.7 (s, OCH
), 7.13 (s, H
), 108.9 (C4a), 113.4 (C
3
2
), 6.42 (d, J =
1
3
2
.0 Hz, H
CDCl ) δ: 55.5 (OCH
CN), 129.6 (C ), 138.7 (C
8
), 6.51 (dd, J = 8.4, 2.4 Hz, H
), 64.4 (C ), 99.3 (C
), 155.9 (C8a), 163.4 (C
7
6
), 7.02 (d, J = 8.8 Hz, H
), 101.9 (C
).
5
4
). C NMR
(
(
3
3
2
8
6
), 117.0
5
4
4.7.4. 5-Methoxy-2H-chromene-3-carbonitrile (9d):
1
Off white solid, yield 70 %. H NMR (CDCl
3
3
) δ: 3.85 (s, OCH ), 4.74 (s, OCH
2
), 6.48 (t, J =
13
8
.0 Hz, 2H, H & H ), 7.21 (t, J = 8.4 Hz, H
6
8
7
), 7.53 (s, H
4
). C NMR (CDCl ) δ: 55.8 (OꢀC),
3

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63.9(C
2
), 100.4 (C
6
), 104.1 (C
8
3 7 4
), 109.0 (C4a), 110.3 (C ), 117.0 (CN), 133.0 (C ), 134.4 (C ),
1
55.1 (C
5
), 156.3 (C8a).
4.8. General procedure for the synthesis of substituted-2H-chromene-3-carboxylic acid
(10a-d): A mixture of 5ꢀmethoxyꢀ2Hꢀchromeneꢀ3ꢀcarbonitrile and 10 % sodium hydroxide
was refluxed for 6 h. The reaction mixture was acidified with con.HCl and the separated
product was washed with water and dried, recrystallization with ethanol to afford desired
compounds.
4.8.1. 2H-chromene-3-carboxylicacid (10a):
1
Yellow solid, yield 90 %. H NMR (DMSOꢀd ) δ: 4.9 (d, J = 1.2 Hz, OCH ), 6.8 (d, J = 8.0
6
2
Hz, H ), 6.95 (td, J = 7.2, 7.6, 0.8, 1.2 Hz, H ), 7.26 (td, J = 8.0, 7.6, 1.6, 1.2 Hz, H ), 7.32
8
6
7
1
3
(
dd, J = 7.6, 7.2, 1.6, 1.2 Hz, H
5
), 7.45 (s, H
4
), 12.86 (s, COOH). C NMR (DMSOꢀd
6
) δ:
),
6
3.5 (C
2
), 115.0 (C
8
), 120.7 (C4a), 121.4 (C
6
), 121.5 (C
5
), 123.4 (C ), 132.4 (C ), 143.3 (C
7
3
4
147.5 (C8a), 165.4 (COOH).
4.8.2. 8-Methoxy-2H-chromene-3-carboxylicacid (10b):
1
Off white solid, yield 85 %. H NMR (DMSOꢀd
6
) δ: 3.75 (s, OCH
), 7.42 (s, H ), 12.8 (s, COOH). C NMR (DMSOꢀ
), 120.7 (C4a), 121.4 (C ), 121.5 (C ), 123.4 (C ), 132.4
), 165.5 (COOH).
3 2
), 4.88 (s, OCH ), 6.9 (m,
13
2
H, H
) δ: 55.6 (OꢀC), 63.9 (C
), 143.4 (C8a), 147.5 (C
6
&H
7
), 7.0 (dd, J = 7.2, 2.8 Hz, H
), 115.0 (C
5
4
d
6
2
7
5
6
3
(C
4
8
4.8.3. 7-Methoxy-2H-chromene-3-carboxylicacid (10c):
1
Off white solid, yield 80 %. H NMR (DMSOꢀd
6
) δ: 3.7 (s, OCH
), 7.4 (s, H ), 12.69 (s, COOH). C NMR
), 107.9 (C ), 113.9 (C4a), 119.8 (C ), 130.1
), 165.6 (COOH).
3 2
), 4.89 (s, OCH ), 6.45 (s,
13
H
8
), 6.55 (d, J = 8.8 Hz, H
DMSOꢀd ) δ: 55.3 (OꢀC), 64.2 (C
), 132.4 (C ), 156.0 (C8a), 162.3 (C
6
), 7.22 (d, J = 8.8 Hz, H
5
4
(
(
6
2
), 101.2 (C
8
6
5
C
3
4
7

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4.8.4. 5-Methoxy-2H-chromene-3-carboxylicacid (10d):
1
Off white solid, yield 85 %. H NMR (DMSOꢀd
6
) δ: 3.82 (s, OCH
), 7.23 (t, J = 8.4 Hz, H
COOH). C NMR (DMSOꢀd ) δ: 55.8 (OꢀC), 63.6 (C ), 104.2 (C ), 108.4 (C ), 110.0 (C ),
3
), 4.83 (s, OCH
2
), 6.47 (d,
J = 8.4 Hz, H
6
), 6.61 (d, J = 8.4 Hz, H
8
7
), 7.55 (s, H ), 12.73 (s,
4
1
3
6
2
6
8
4a
1
21.3 (C ), 127.0 (C ), 132.3 (C ), 155.1 (C ), 156.4 (C ), 165.4 (COOH).
7 3 4 5 8a
4.9. General procedure for the synthesis of 2-bromo-1-(substituted-phenyl)ethanone
3
3
derivatives (12a-h): Following the literature method , to a stirred solution of acetophenone
5 g, 0.041 mol) in diethyl ether (30 ml) in an ice bath bromine (2.08 ml, 0.041 mol) in
(
dichloromethane (30 ml) was added drop wise over 10ꢀ15 minutes. After addition, the
solution stirred 2 hour at rt. The solvent evaporated under reduced pressure and triturated
with petꢀether and kept in freeze for few hours, the separated solid was filtered to get the
desired compounds 12a-h.
4.9.1. 2-Bromo-1-phenylethanone (12a):
1
Off white solid, yield 85 %. H NMR (CDCl ) δ: 4.46 (s, CH ), 7.5 (t, J = 8.0, 7.6 Hz, 2H,
3
2
13
H
3
&H
5
), 7.61 (t, J = 7.2 Hz, H
4
), 7.99 (d, J = 8.4 Hz, 2H, H
2
6 3
& H ). C NMR (CDCl ) δ: 30.9
(
CꢀBr), 128.8 (C
2
&C ), 128.9 (C &C ), 131.7 (C ), 133.9 (C ), 191.2 (C=O).
6
3 5 4 1
4.9.2. 2-Bromo-1-(4-chlorophenyl)ethanone (12b):
1
Brown solid, yield 70 %. H NMR (CDCl
3
) δ: 4.41 (s, CH
2
), 7.34 (d, J = 8.8, 2H, H
3
& H
5
),
1
3
7
.84 (d, J = 8.4, 2H, H & H ). C NMR (CDCl ) δ: 30.5 (CꢀBr), 129.3 (C &C ), 130.4
2 6 3 3 5
(
C &C ), 132.2 (C ), 132.6 (C ), 190.4 (C=O).
2 6 1 4
4.9.3. 2-Bromo-1-(2, 4-chlorophenyl)ethanone (12c):

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1
Brown oil, yield 60 %. H NMR (CDCl
3
) δ: 4.25 (s, CH
) δ: 30.5 (CꢀBr), 126.9 (C ), 130.4 (C ), 132.0 (C
4
), 190.4 (C=O).
2
), 7.5 (s, H
3
), 7.65 (m, 2H, H
5
&H
6
).
),
1
3
C NMR (CDCl
42.1 (C
3
5
3
6
), 132.8 (C ), 133.2 (C
2
1
1
4.9.4. 2-Bromo-1-(3-nitrophenyl)ethanone (12d):
1
Off white solid, yield 70 %. H NMR (CDCl ) δ: 4.48 (s, CH ), 7.74 (t, J = 8.0 Hz, H ), 8.33
3
2
5
1
3
(d, J = 8 Hz, H
6
4
), 8.48 (d, J = 8.4 Hz, H ), 8.81 (s, H
2
). C NMR (CDCl
3
) δ: 30.8 (CꢀBr),
1
22.7 (C
2
), 123.5 (C ), 127.6 (C
4
5
), 133.6 (C
6
), 137.2 (C
1
), 145.3 (C ), 190.9 (C=O).
3
4.9.5. 2-Bromo-1-(4-bromophenyl)ethanone (12e):
1
Brown solid, yield 75 %. H NMR (CDCl ) δ: 4.41 (s, CH ), 7.65 (d, J = 8.8 Hz, 2H,
3
2
1
3
H &H ), 7.85 (d, J = 8.4 Hz, 2H, H &H ). C NMR (CDCl ) δ: 30.5 (CꢀBr), 129.3 (C ),
3
5
2
6
3
4
1
30.2 (C
2
&C
6
), 132.2 (C
3
&C
5
), 132.3 (C
1
), 190.2 (C=O).
4.9.6.1-(4-(Benzyloxy) phenyl)-2-bromoethanone (12f):
1
Off white solid, yield 65 %. H NMR (CDCl
3
) δ: 4.39 (s, CH
2
ꢀBr), 5.14 (s, BnꢀCH
2
), 7.03
(
dd, J = 6.8, 2.0 Hz, 2H, H &H ), 7.4 (m, 5H, H ) 7.97 (dd, J = 6.8, 2.0 Hz, 2H, H &H ).
3 5 1’ꢀ5’ 2 6
1
3
C NMR (CDCl
3
) δ: 30.5 (CꢀBr), 69.7 (BnꢀCH
2
), 114.2 (C
3
&C
5
), 127.1 (C2’&C6’), 127.4
), 190.3 (C=O).
(C
4
), 127.7 (C3’ &C5’), 128.1 (C
1
) 130.2 (C &C ), 140.2 (C1’), 166.4 (C
2
6
4
4.9.7.2-Bromo-1-(4-fluorophenyl)ethanone(12g):
1
Off white solid, yield 85 %. H NMR (CDCl
3
) δ: 4.42 (s, CH
2
), 7.17 (t, J = 8.8, 8.4 Hz, 2H,
13
H &H ), 8.03 (dd, J = 9.2, 5.6 Hz, 2H, H &H ). C NMR (CDCl ) δ: 30.5 (CꢀBr), 112.4
3
5
2
6
3
(
C &C ), 129.3 (C &C ), 130.4 (C ), 160.3 (C ), 190.2 (C=O).
3 5 2 6 1 4
4.9.8. 2-Bromo-1-(4-methoxyphenyl)ethanone (12h):

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1
Brown solid, yield 70 %. H NMR (CDCl
Hz, 2H, H &H ), 7.97 (d, J = 8.8 Hz, 2H, H
OꢀC), 114.3 (C &C ), 128.2 (C ), 131.3 (C &C
3
) δ: 3.38 (s, OꢀCH
3
), 4.4 (s, CH
). C NMR (CDCl ) δ: 30.8 (CꢀBr), 55.5
), 164.1 (C ), 189.9 (C=O).
2
), 6.96 (d, J = 8.8
13
3
5
2
&H
6
3
(
3
5
1
2
6
4
4.9.9. 2-Bromo-1-(pyridin-3-yl)ethanone (12i):
3
4
Following the literature method , 3ꢀacetyl pyridine (11i) (5 g, 0.04 mol) was added to 33%
HBr/AcOH (50 ml) with stirring. Bromine (2.04 ml, 0.04 mol) was then added and the
reaction mixture was heated to 60 °C for 2h. The solution was cooled to rt and diethyl ether
(50 ml) was added. The separated solid was filtered, washed with diethyl ether and dried to
1
give 2ꢀbromoꢀ1ꢀ(pyridinꢀ3ꢀyl) ethanone (12i). White solid 5.6 g, 70 %. H NMR (CDCl
3
) δ:
1
3
4
.39 (s, CH
2
), 7.9 (m, 3H, H
, H
4 5
&H
6
), 9.13 (s, H
2 3
). C NMR (CDCl ) δ: 31.5 (CꢀBr), 121.3
(C
5
), 123.3 (C
1
), 131.6 (C ), 145.4 (C
6
4
), 147.5 (C ), 190.2 (C=O).
2
4.9.10. 2-Bromo-1-(thiophen-2-yl)ethanone (12j):
35
Following the literature method , a solution of bromine (1.98 ml, 0.039 mol) in
dichloromethane (20 ml) was added drop wise to 2ꢀacetylthiophene (11j) (5 g, 0.039 mol) in
dichloromethane (30 ml) in 20 min. The reaction mixture was stirred at 25 °C for 2h and
neutralized with a saturated solution of NaHCO
3
. The organic layer was washed with water
followed by brine and dried over Na SO , filtered. Removal of the solvent gives a residue
2
4
which was purified by column chromatography (silica gel, ethyl acetate/petꢀether 5:95 as
1
eluent). Yellow oil 6 g, 73.6%. H NMR (CDCl ) δ: 4.37 (s, CH ), 7.17 (dd, J = 4.8, 4.0 Hz,
3
2
13
H
4
), 7.73 (dd, J = 3.6, 1.2 Hz, H
3
5 3
), 8.81 (dd, J = 4.8, 1.2 Hz, H ). C NMR (CDCl ) δ: 31.1
(
CꢀBr), 128.6 (C ), 133.7 (C ), 135.4 (C ), 140.7 (C ), 184.4 (C=O).
4
3 5 2
4.10. General procedure for preparation of 2-(substituted -2H-chromen-3-yl)-5-aryl-
1H-imidazoles (13-16):

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To a mixture of substitutedꢀ2Hꢀchromeneꢀ3ꢀcarboxylicacid (10a-d) (1.0 mol) and
triethylamine (3.0 mol) in dichloromethane in an ice both was added acyl bromides (12a-f)
(1.2 mol), the solution stirred overnight at rt. The reaction mixture was diluted with
chloroform and washed with water and brine solution, successively, and dried over Na SO ,
2
4
after removal of the solvent under reduced pressure; the residue was washed with petꢀether
and dried under vacuum. The residue was dissolved in toluene and treated with ammonium
acetate (5.0 mol) under nitrogen atmosphere. The reaction mixture was refluxed for 12 hour
3
and was monitored by TLC. The reaction mixture was quenched with saturated NaHCO . The
product was extracted with ethyl acetate (2 times), and washed with water followed by brine
solution, successively and dried over Na SO . After removal of the solvent under reduced
2
4
pressure, the crude product was purified by column chromatography using petroleum
ether/ethyl acetate.
4.10.1 .(2H-chromen-3-yl)-5-phenyl-1H-imidazole (13a):
1
Yellow solid; yield 50%; mp.165ꢀ170 °C; H NMR (CDCl ) δ: 5.29 (s, OꢀCH ), 6.85 (t, J =
3
2
8.4, 9.2 Hz, H
6
), 6.9 (d, J = 7.2 Hz, H
8
), 7.03 (d, J = 7.2 Hz, H
5
7
) 7.14 (t, J = 8.0, 7.6 Hz, H ),
7.25 (s, H4’), 7.29 (d, J = 7.2 Hz, 2H, H2’’& H6’’), 7.34 (s, H
4
), 7.37 (t, J = 8.0, 2.8 Hz, 3H,
1
3
H
3”, H4”&H5”), 7.69 (s, NH), CNMR (DMSOꢀd
6
) δ: 64.7 (C ), 114.8 (C ), 115.4 (C4a),
2
8
1
18.6 (C4’), 121.7 (C
6
), 122.4 (C
5
), 123.2 (C
7
), 124.3 (C2’’& C6’’), 126.3 (C4’’), 127.0 (C3”
ꢀ
&
C ), 128.4 (C ), 129.1 (C ), 134.3 (C ), 141.0 (C ), 143.2 (C ), 153.2 (C ); IR (KBr, Cm
5” 4 1’’ 2’ 3 5’ 8a
1
): 3162 (NꢀH), 1578 (C=N); MS (ESI, m/z): 275.07.
4.10.2.5-(4-Chlorophenyl)-2-(2H-chromen-3-yl)-1H-imidazole (13b):
1
Brown solid; yield 45%; mp.180ꢀ185 °C; H NMR (CDCl
3
) δ: 5.33 (s, OꢀCH
), 7.1 (dd, J = 7.6, 1.2 Hz, H
.19 (td, J = 8.0, 7.6, 1.6, 1.2 Hz, H ), 7.28 (s, H ), 7.38 (d, J = 8.0 Hz, 4H, H , H , H &
2
), 6.86 (s, H4’),
6.91 (d, J = 8.0 Hz, H
8
), 6.94 (td, J = 7.2, 7.6, 0.8, 1.2 Hz, H
6
5
),
7
7
4
2’
3’
5’

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1
3
H
6’), 7.71 (s, NH). C NMR (DMSOꢀd
21.7 (C ), 122.3 (C ), 125.9 (C ), 127.1 (C2’’ & C6’’), 128.4 (C3”& C5”), 129.2 (C
1’’), 133.2 (C4”), 139.8 (C2’ & C
6
) δ: 64.7 (C
2
), 115.4 (C
8
), 115.5 (C4a), 118.9 (C4’),
), 130.5
3
), 143.4 (C5’), 153.2 (C8a); IR (KBr, Cm ): 3162 (NꢀH),
1
6
5
7
4
ꢀ1
(C
1577 (C=N);MS (ESI, m/z): 308.97, 310.98
4.10.3.5-(2, 4-Dichlorophenyl)-2-(2H-chromen-3-yl)-1H-imidazole (13c):
1
Yellow solid; yield 45%; mp.190ꢀ195 °C; H NMR (CDCl
3
) δ: 5.34 (s, OCH
), 7.12 (d, J = 8.8 Hz, 2H, H & H3”), 7.2 (t, J =
& H5”), 7.34 (d, J = 10.4 Hz, H2”), 7.47 (s, NH). C NMR
2
), 6.88 (s, H4’),
6
.91 (d, J = 9.2 Hz, H
8
), 6.95 (t, J = 8.4 Hz, H
6
5
1
3
7
.6 Hz, H ) 7.28 (s, 2H, H
7
4
(
(
(
CDCl ) δ: 64.6 (C ), 115.5 (C ), 115.84 (C ), 118.9 (C ), 121.75 (C ), 122.2 (C ), 125.3
3 2 8 4a 4’ 6 5
C
C
7
3
& C5’’), 127.1 (C1’’), 129.2 (C
4
,), 130.5 (C6’’& C3’’ ), 133.1 ((C2’’), 133.2 (C4’’), 139.8
ꢀ1
&C2’), 143.4 (C5’), 153.2 (C8a); IR (KBr, Cm ): 3168 (NꢀH), 1581 (C=N); MS (ESI, m/z):
342.93, 344.95.
4.10.4.5-(4-Bromophenyl)-2-(2H-chromen-3-yl)-1H-imidazole (13e):
1
Pale yellow solid; yield 52%; mp.165ꢀ170 °C. H NMR (CDCl ) δ: 5.34 (s, OCH ), 6.88 (m,
3
2
3H, H , H & H ), 7.11 (d, J = 7.6 Hz, H ), 7.19 (t, J = 6.4 Hz, H ), 7.39 (s, H ), 7.54 (d, J =
8 6 4’ 5 7 4
1
3
1
5.6 Hz, 2H, H2”&H6”), 7.65 (d, J = 11.6 Hz, 2H, H3”& H5”). C NMR (DMSOꢀd
), 115.5 (C ), 118.9 (C4a), 119.0 (C4’), 121.7 (C ), 122.3 (C ), 123.0 (C4’’), 126.3 (C
27.1 (C2”& C6’’), 129.2 (C ), 131.3 (C1’’), 133.6 (C3’’& C5’’), 139.8 (C &C2’), 143.4 (C5’),
6
) δ: 64.7
(C
2
8
6
5
7
),
1
1
4
3
ꢀ1
53.2 (C8a); IR (KBr, Cm ): 3017 (NꢀH), 1576 (C=N); MS (ESI, m/z):354.94, 355.94.
4.10.5.5-(4-(Benzyloxy) phenyl)-2-(2H-chromen-3-yl)-1H-imidazole (13f):
1
Pale yellow solid; yield 45%; mp.170ꢀ175 °C. H NMR (DMSOꢀd
6
) δ: 5.12 (s, OCH
2
), 5.48
2 8 6
(s, BnꢀOCH ), 6.9 (m, 3H, H , H & H4’), 7.04 (d, J = 8.0 Hz, 2H, H3”& H5”), 7.23 (m, 2H,
13
H
5
& H ), 7.41 (m, 6H, H2’’’ꢀ6’’’& H ), 7.7 (d, J = 8.4 Hz, 2H, C2”& C6”), 12.2 (s, NH). C
7
4

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NMR (DMSOꢀd
6
) δ: 64.7 (C
18.3 (C4’), 121.7 (C ), 122.4 (C
27.7 (C2’’ & C6’’), 128.4 (C3’’’& C5’’’), 129.1 (C
2
), 69.2 (BnꢀOꢀC), 113.6 (C3’’& C5’’), 114.8 (C
8
), 115.4 (C4a),
1
1
1
6
5
), 125.6 (C
7
), 125.9 (C1’’), 126.9 (C2’’’& C6’’’), 127.3 (C4’’’),
& C2’), 140.9 (C1’’’), 142.9 (C5’),
4
), 137.1 (C
3
ꢀ1
53.2 (C8a), 157.1 (C4’’); IR (KBr, Cm ): 3061 (NꢀH), 1575 (C=N); MS (ESI, m/z): 381.06.
4.10.6.2-(2H-chromen-3-yl)-5-(4-fluorophenyl)-1H-imidazole (13g):
1
Pale yellow solid; yield 40%; mp.160ꢀ165 °C. H NMR (CDCl
3
) δ: 5.31 (d, J = 1.6Hz, 2H,
), 7.09 (m,
), 7.31 (s,H ), 7.7 (s,
OCH
2
), 6.84 (s, H
4 8 6
), 6.88 (d, J = 8 Hz, H ), 6.92 (td, J = 8.0, 1.6, 7.2, 1.2 Hz, H
5H, H
5
, H2’’, H3’’, H5’’, H6’’), 7.17 (td, J = 7.6, 1.2, 8.0, 1.6 Hz, 1H,H
7
4
1
3
NH). C NMR (DMSOꢀd
6
) δ: 64.7 (C
), 126.1 (C
&C2’), 143.2 (C5’), 153.2 (C8a), 159.7 (C4’’); IR (KBr, Cm ): 3116 (NꢀH), 1577 (C=N);
2
), 114.6 (C
8
), 115.1 (C4a), 115.3 (C3’’’& C5’’’), 118.7
(
C
C
4’), 121.7 (C
6
), 122.3 (C
5
7
), 126.2 (C1’’), 127.0 (C2’’& C6’’), 129.2 (C ), 140.1
4
ꢀ1
(
3
MS (ESI, m/z): 293.07.
4.10.7. 2-(2H-chromen-3-yl)-5-(4-methoxyphenyl)-1H-imidazole (13h):
1
Light green solid; yield 42%; mp.150ꢀ155 °C. H NMR (CDCl ) δ: 3.88 (s, OCH ) , 5.44 (s,
3
3
OCH
2
) , 6.84 (s, H4’), 6.86 (d , J = 8 Hz, H
8
), 6.93 (td, J = 7.2, 0.8, 7.6, 1.2Hz, H
6
), 6.97 (d, J
=
8.8 Hz, 2H, H3’’& H5’’), 7.16 (dd, J = 7.6, 2.0, 7.2, 1.6 Hz, H
.2 Hz, H ), 7.59 (s, H ), 7.71 (s, NH), 7.92 (d, J = 8.8 Hz, H2’’&H6’’). CNMR (DMSOꢀd
δ: 55.6 (C ), 65.5 (OꢀC), 113.6 (C3’’&C5’’), 114.1 (C ), 115.8 (C4a), 120.6 (C4’), 121.6 (C
22.0 (C ), 126.7 (C &C ), 129.4 (C & C ), 130.1 (C ), 140.5 (C & C ), 141.4 (C ),
5
), 7.25 (td, J = 8.0, 1.6, 7.6,
13
1
7
4
6
)
2
8
6
),
1
1
5
7
1’’
2’’
6’’
4
3
2’
5’
ꢀ1
50.6 (C ), 163.2 (C ); IR (KBr, Cm ): 3068 (NꢀH), 1573 (C=N); MS (ESI, m/z): 305.
8
a
4’’
4.10.8.3-(2-(2H-chromen-3-yl)-1H-imidazol-5-yl) pyridine (13i):
1
Brown solid; yield 45%; mp.265ꢀ270 °C. H NMR (DMSOꢀd
6
) δ: 5.23 (s, OCH
3
), 6.76 (d, J =
), 7.96
8
.0 Hz, H
8
), 6.96 (t, J = 7.2 Hz, H
6
), 7.17 (m, 3H, H
5
, H
4
& H4’), 7.4 (t, J = 4.8 Hz, H
7

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1
3
(
s, H4’’), 8.15 (dt, J = 2.0 Hz, H5’’), 8.42 (d, J = 3.6 Hz, H6’’), 9.03 (s, H2’’), 12.82 (s, NH). C
NMR (DMSOꢀd ) δ: 64.6 (C ), 115.5 (C ), 119.1 (C4a), 121.7 (C4’), 122.2 (C ), 122.9 (C ),
23.6 (C5’’), 127.1 (C ), 128.1 (C ), 128.8 (C3’’), 129.3 (C4’’), 131.3 (C ), 143.9 (C2’), 145.8
C & C ), 147.3 (C ), 153.2 (C ); IR (KBr, Cm ): 3128 (NꢀH), 1573 (C=N); MS (ESI,
6
2
8
6
5
1
7
4
3
ꢀ1
(
6
’’
5’
2’’
8a
+
m/z): 276.02 ([M+1] .
4.10.9.2-(2H-chromen-3-yl)-5-(thiophen-2-yl)-1H-imidazole (13j):
1
Brown solid; yield 47%; mp.170ꢀ175 °C. H NMR (DMSOꢀd
6
) δ: 5.27 (d, J = 1.6 Hz, OCH
), 7.04 (m, 2H, H
), 7.23 (dd, J = 4.8, 0.8, 5.2, 1.2 Hz, H3’’), 7.26 (s, H
.27 (d, J = 3.6 Hz, H5’’). C NMR (DMSOꢀd ) δ: 64.6 (C ), 115.4 (C ), 118.9 (C4a), 121.7
), 122.2 (C5’), 122.8 (C & C5’’), 127.1 (C &C3’’), 127.6 (C & C4’’), 129.2 (C
4.1 (C2’), 153.2 (C8a); IR (KBr, Cm ): 3023 (NꢀH), 1578 (C=N); MS (ESI, m/z): 281.12
2
),
6
7
7
.84 (s, H4’), 6.86 (t, J = 9.2 Hz, H
8
), 6.9 (td, J = 7.2, 1.2 Hz, H
6
5
& H4’’),
.15(td, J = 8.0, 1.6, 7.6, 1.2Hz, H
7
4
),
1
3
6
2
8
(C
4’& C
6
5
7
4
3
& C2’’),
ꢀ1
1
+
+
+
(
[M+1] , 282.16 [M+2] , 283.05 [M+3] .
4.10.10. 2-(8-Methoxy-2H-chromen-3-yl)-5-phenyl-1H-imidazole (14a):
1
White solid; yield 55%; mp.145ꢀ150 °C. H NMR (DMSOꢀd
6
) δ: 3.78 (s, OCH
& H4’), 7.15 (s, H ), 7.2 (t, J =
), 7.36 (t, J = 7.6, 8.0 Hz, 2H, H3’’&H5’’),7.44 (t, J = 7.6, 8.0 Hz, H4’’) 7.82 (d,
3
), 5.19 (s,
OCH
.2, 7.6 Hz, H
J = 7.6 Hz, 2H, H2’’& H6’’), 12.69 (s, NH). C NMR (DMSOꢀd
2
), 6.78 (dd, J = 6.8, 2.0, 7.2, 2.4 Hz, H
7
), 6.9 (m, 2H, H
5
4
7
6
13
6
) δ: 55.6 (OꢀC), 64.6 (C
2
),
1
1
12.8 (C ), 114.8 (C ), 118.7 (C ), 119.1 (C ), 121.4 (C ), 122.3 (C &C ), 126.2(C ),
7
4a
5
4’
6
2’’
6’’
4’’
28.4 (C3’’& C5’’), 128.8 (C
4
), 134.3 (C1’’), 141.0 (C
3
& C2’), 142.0 (C5’), 143.2 (C8a), 147.5
ꢀ1
+
(C
8
); IR (KBr, Cm ): 3119 (NꢀH), 1571 (C=N);MS (ESI, m/z): 305.06 ([M+H] .
4.10.11.5-(4-Bromophenyl)-2-(8-methoxy-2H-chromen-3-yl)-1H-imidazole (14e):

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1
Yellow solid; yield 55%; mp.155ꢀ160 °C. H NMR (CDCl
3
ꢀd
6
): δ 3.89 (s, 3H, OCH
3
), 5.34
), 7.49
d, J = 8.4 Hz, 2H, H3’’& H5’’), 7.6 (d, J = 8 Hz, 2H, H2’’& H6’’). C NMR (DMSOꢀd ) δ:
5.6 (OꢀC), 64.5 (C ), 112.9 (C ), 115.0 (C ), 119.1 (C ), 120.7 (C ), 121.4 (C ), 122.9
(
s, 2H, OCH
2
), 6.71 (d, J = 6.8 Hz, 1H, H
7
), 6.83 (m, 3H, H6,
H
4’&H
5
), 7.35 (s, 1H, H
4
13
(
6
5
2
7
4a
5
4’
6
(C ), 126.3 (C ), 128.7 (C & C ), 131.3 (C ), 132.4 (C &C ), 142.0 (C & C ), 143.5
4’’ 4 2’’ 6’’ 1’’ 3’’ 5’’ 3 2’
ꢀ1
(C
8
5’), 144.7 (C8a), 147.5 (C ); IR (KBr, Cm ): 3123 (NꢀH), 1576 (C=N); MS (ESI, m/z):
+
3
86.24 [M+2] .
4.10.12.5-(4-(Benzyloxy)phenyl)-2-(8-methoxy-2H-chromen-3-yl)-1H-imdazole (14f).
1
Pale green solid; yield 40%; mp.150ꢀ160 °C. H NMR (DMSOꢀd
6
) δ: 3.77 (s, OCH
), 6.9 (m, 2H, H & H
, Bnꢀ5H), 7.72 (d, J = 8.4 Hz, 2H,
) δ: 56.1 (OꢀC), 65.1 (C ), 69.7 (BnꢀOꢀC),
), 115.4 (C3’’, C5’’& C4a), 119.0 (C4’), 119.5 (C ), 121.9 (C ), 123.6 (C1’’), 126.2
C & C ), 127.9 (C ), 128.2 (C & C ), 128.3 (C & C ), 128.9 (C ), 137.6 (C &
3
), 5.12 (s,
OCH
2
), 5.16 (s, OCH
2
), 6.82 (dd, J = 6.4, 2.0, 6.8, 2.4 Hz, H
7
6
5
), 7.04 (d,
J = 6.8 Hz, 2H, H3’’& H5’’), 7.16 (s, H4’), 7.4 (m, 6H, H
4
13
H
2’’& H6’’), 12.5 (s, NH). C NMR (DMSOꢀd
6
2
113.3 (C
7
5
6
(
2
’’’
6’’’
4’’’
2’’
6’’
3’’’
5’’’
4
3
ꢀ1
C
2’), 142.5 (C5’), 143.6 (C1’’’), 148.0 (C
8
& C8a), 157.7 (C4’’); IR (KBr, Cm ): 3082 (NꢀH),
+
1
576 (C=N);MS (ESI, m/z): 411.04 ([M+1] .
4.10.13.5-(4-Fluorophenyl)-2-(8-methoxy-2H-chromen-3-yl)-1H-imidazole (14g).
1
Pale green solid; yield 45%; mp.135ꢀ140 °C. H NMR (CDCl3) δ: 3.9 (s, OCH
3
), 5.36 (s,
OCH ), 6.72 (d, J = 7.2 Hz, H ), 6.82 (d, J = 7.2 Hz, H ), 6.88 (t, J = 7.2 Hz, H ), 6.88 (s,
2
7
5
6
H
4’), 7.08 (t, J = 8.4, 8.8 Hz, 2H, H2’’& H6’’), 7.3 (s, H
4
), 7.7 (t, J = 8.8, 10.8, 2H, H3’’& H6’’).
), 112.9 (C ), 115.2 (C4a), 115.4 (C3’’ & C5’’),
), 122.0 (C1’’), 126.2 (C2’’& C6’’), 126.2 (C ), 142.0 (C
), 162.2 (C4’’); IR (KBr, Cm ): 3081 (NꢀH), 1579
1
3
C NMR (DMSOꢀd
18.9 (C ), 119.1 (C4’), 121.4 (C
2’), 143.6 (C5’), 147.5 (C8a), 159.8 (C
6
) δ: 55.6 (OꢀC), 64.5 (C
2
7
1
5
6
4
3
&
ꢀ1
C
8
+
(
C=N); MS (ESI, m/z): 323.09 [M+1] .

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4.10.14. 2-(8-Methoxy-2H-chromen-3-yl)-5-(4-methoxyphenyl)-1H-imidazole (14h).
1
Brown solid; yield 40%; mp.150ꢀ155 °C. H NMR (DMSOꢀd
6
) δ: 3.77 (s, 2xOCH ), 5.17 (s,
3
OCH
2
), 6.78 (dd, J = 6.0, 2.8 Hz, H
6
), 6.89 (s, H4’), 6.9 (d, J = 2.8 Hz, 2H, H
7
& H ), 6.96 (d,
5
J = 8.0 Hz, 2H, H & H ), 7.16 (s, H ), 7.72 (d, J = 8.8 Hz, 2H, H & H ), 12.61 (s, NH).
3
’’
5’’
4
2’’
6’’
1
3
C NMR (DMSOꢀd
18.9 (C4a), 119.5 (C4’& C ), 136.5
8
& C2’), 142.5 (C5’), 143.6 (C8a), 148.0 (C ), 158.6 (C4’’); IR (KBr) Cm : 3130 (NꢀH),
6
) δ: 55.5 (OꢀC), 56.1 (OꢀC), 65.1 (C
2
), 113.2 (C
7
), 114.5 (C3’’& C5’’),
1
5
), 121.9 (C
6
), 123.6 (C1’’), 126.2 (C2’’& C6’’), 129.1 (C
4
ꢀ1
(C
3
+
1
575 (C=N); MS (ESI, m/z): 335.12 [M+1] .
4.10.15.3-(2-(8-Methoxy-2H-chromen-3-yl)-1H-imidazole-5-yl)pyridine(14i).
1
Brown solid; yield 40%; mp.225ꢀ230 °C. H NMR (DMSOꢀd ) δ: 3.78 (s, OCH ), 5.19 (s,
6
3
OCH
2
), 6.8 (d, J = 6 Hz, H
), 8.15 (d, J = 8.0 Hz, H6’’), 8.42 (d, J = 3.2 Hz, H4’’), 9.03 (s, H2’’), 12.82 (s,
NH). C NMR (DMSOꢀd ) δ: 56.1 (OꢀC), 65.0 (C ), 113.5 (C ), 119.6 (C4a), 119.8 (C ),
21.9 (C ), 123.4 (C ), 124.1 (C ), 128.0 (C ), 133.0 (C ), 136.0 (C & C ), 131.8 (C ),
7 5 6
), 6.9 (m, 2H, H & H ), 7.19 (s, H4’), 7.41 (t, J = 4.8, 6.0 Hz,
H
5’’), 7.93 (s, H
4
1
3
6
2
7
5
1
1
1
4
’
6
5’’
4
4’’
3
2’
3’’
ꢀ1
42.6 (C ), 144.4 (C ), 146.3 (C ), 147.8 (C ), 148.0 (C ); IR (KBr, Cm ): 3085 (NꢀH),
5
6’’
8a
2’’
8
+
581 (C=N); MS (ESI, m/z): 306.12 [M+1] .
4.10.16. 5-2-(8-Methoxy-2H-chromen-3-yl)-5-(thiophen-2-yl)-1H-imidazole (14j).
1
Pale green solid; yield 40%; mp.155ꢀ160 °C. H NMR (DMSOꢀd
6
) δ: 3.77 (s, OCH
3
), 5.14 (s,
OCH ), 6.78 (dd, J = 6.4, 1.6, 6.8, 2.0 Hz, H ), 6.91 (m, 2H, H & H ), 7.05 (dd, J = 4.8, 3.6
2
6
7
4’
Hz, H4’’), 7.14 (s, H
4
), 7.31 (d, J = 3.6 Hz, H3’’), 7.36 (d, J = 5.2 Hz, H
5
), 7.67 (d, J = 1.6 Hz,
), 113.4 (C ), 114.6 (C4a),
& C4’), 121.9 (C6’), 122.0 (C5’), 123.3 (C5’’), 123.5 (C3’’), 123.8 (C4’’), 128.1 (C ),
1
3
H
5’’), 12.7 (s, NH). C NMR (DMSOꢀd
6
) δ: 56.1 (OꢀC), 65.0 (C
2
7
1
19.6 (C
5
4

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ꢀ1
1
37.0 (C2’’), 138.6 (C2’), 142.5 (C
3
8
), 143.5 (C8a), 148.0 (C ); IR (KBr, Cm ): 3086 (NꢀH),
+
+
+
1
574 (C=N); MS (ESI, m/z): 311.01 [M+1] , 312.16 [M+2] , 313.06 [M+3] .
4.10.17. 2-(7-Methoxy-2-H-chromen-3-yl)-5-phenyl-1-H-imidazole (15a).
1
Yellow solid; yield50%; mp.155ꢀ160 °C. H NMR (CDCl
3
+DMSOꢀd
6
) δ: 3.78 (s, OCH
3
),
5
7
7
.28 (s, OCH ), 6.46 (s,H ), 6.48 (d, J = 2.4 Hz, H ), 6.81 (s, H ), 6.96 (d, J = 8.0 Hz, H ),
2 8 6 4’ 5
4
.27 (t, J = 7.6, 4.0 Hz, H4’’), 7.34 (s, H ), 7.39 (t, J = 7.6 Hz, 2H,H3’’& H5’’), 7.69 (d, J =
13
.2Hz, 2H, H2’’& H6’’),12.12 (s, NH). C NMR (DMSOꢀd
6
2
) δ: 55.2 (OꢀC), 64.8 (C ), 101.5
(C
8
), 107.6 (C ), 115.4 (C4a), 118.7 (C4’), 124.3 (C2’’& C6’’), 127.8 (C
6
5
), 128.5 (C , C3’’&
4
ꢀ1
C
5’’), 134.2 (C1’’), 138.7 (C2’& C
3
7
), 143.7 (C5’), 154.5 (C8a), 160.4 (C ); IR (KBr, Cm ): 3000
+
(
NꢀH), 1572 (C=N); MS (ESI, m/z): 305.06 [M+1] .
4.10.18.5-(4-Bromophenyl)-2-(7-methoxy-2-H-chromen-3-yl)-1-H-imidazole (15e).
1
Yellow solid; yield 45%; mp.175ꢀ180 °C. H NMR (CDCl
3
) δ: 3.79 (s, OCH
3
), 5.27 (s,
),
OCH
2
), 6.47 (s, H
8
), 6.5 (d, J = 2.0 Hz, H
6
), 6.8 (s, H4’), 6.98 (d, J = 8.4 Hz, H
5
), 7.32 (s, H
4
1
3
7
.5 (d, J = 8.8 Hz, 2H, H & H ), 7.6 (d, J = 7.6 Hz, 2H, H & H ). C NMR (DMSOꢀd )
2’’ 6’’ 3’’ 5’’ 6
δ: 55.3 (OꢀC), 64.7 (C
2
), 101.5 (C
8
6
), 107.7 (C ), 115.3 (C4a), 118.9 (C4’), 119.9 (C4’’), 126.2
(C
5
, C2’’& C6’’), 127.9 (C
4
, C3’’& C5’’), 131.3 (C1’’), 137.8 (C2’& C
3
), 143.9 (C5’), 154.6 (C8a),
ꢀ
1
+
1
60.5 (C
7
); IR (KBr, Cm ): 3085 (NꢀH), 1570 (C=N); MS (ESI, m/z): 386[M+2] .
4.10.19.5-(4-(Benzyloxy)phenyl)-2-(7-methoxy-2-H-chromen-3-yl)-1-H-imidazole
(15f).
1
Yellow solid; yield 45%; mp.320ꢀ330 °C. H NMR (DMSOꢀd ) δ: 3.75 (s, OCH ), 4.88 (s,
6
3
OCH
2
), 5.12 (s, OCH
.0 Hz, H ), 7.41 (s, H
2’’& H6’’), 7.72 (d, J = 8.4 Hz, 2H, H2’’& H6’’), 12.6 (s, NH). C NMR (DMSOꢀd
), 69.7 (BnꢀOꢀC), 113.3 (C ), 115.4 (C3’’, C5’’& C4a), 119.0 (C4’), 119.5 (C
2
), 6.55 (d, J = 8.4, 2H, H3’’& H5’’), 7.11 (d, J = 8.4 Hz, H
6
), 7.25 (d, J =
8
5
4
), 7.44 (t, J = 7.6 Hz, 3H, H3’’’, H4’’’& H5’’’), 7.47 ( d, J = 6.8 Hz, 2H,
13
H
6
) δ: 56.1
),
(OꢀC), 65.1 (C
2
8
5

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121.9 (C
6
), 123.6 (C1’’), 126.2 (C2’’’& C6’’’), 127.9 (C4’’’), 128.2 (C2’’& C6’’), 128.3 (C3’’’
&
C
5’’’), 128.9 (C & C2’), 142.5 (C5’), 143.6 (C1’’’), 148.0 (C & C8a), 157.7 (C4’’); IR
4
), 137.6 (C
3
7
ꢀ1
+
(
KBr, Cm ): 3007 (NꢀH), 1597 (C=N);MS (ESI, m/z): 411.04 [M+1] .
4.10.20. 5-(4-Fluorophenyl)-2-(7-methoxy-2-H-chromen-3-yl)-1-H-imidazole (15g).
1
Yellow solid; yield 50%; mp.165ꢀ170 °C. H NMR (DMSOꢀd ) δ: 3.75 (s, OCH ), 5.17 (s,
6
3
OCH
2
), 6.49 (d, J = 2.4 Hz, H
8
), 6.55 (dd, J = 8.0, 2.4, 8.4, 2.8 Hz, H
6
), 7.1 (d, J = 8.4 Hz,
H
5
), 7.14 (s, H4’), 7.2 (t, J = 6.8Hz, 2H, H2’’& H6’’), 7.73 (s, H
4
), 7.83 (dd, J = 8.8, 8.0 Hz,
) δ: 55.3 (OꢀC), 64.8 (C ), 101.5 (C ),
), 115.3 (C4a), 118.8 (C3’’& C5’’), 120.0 (C4’), 126.1 (C ), 126.2 (C1’’), 127.8 (C
13
2
H, H2’’& H6’’), 12.57 (s, NH). C NMR (DMSOꢀd
07.6 (C
6
2
8
1
6
5
4
,
ꢀ1
C
2’’&C6’’), 139.2 (C2’& C
3
4
), 143.7 (C5’), 154.5 (C8a), 160.0 (C ), 162.1 (C4’’); IR (KBr, Cm ):
+
3
039 (NꢀH), 1572 (C=N); MS (ESI, m/z): 323 [M+1] .
4.10.21.2-(7-Methoxy-2-H-chromen-3-yl)-5-(4-methoxyphenyl)-1-H-imidazole (15h).
1
Brown solid; yield 45%; mp.135ꢀ140 °C. H NMR (DMSOꢀd
6
) δ: 3.75 (s, OCH
3
), 3.85 (s,
OCH ), 5.5 (s, OCH ), 6.45 (m, 2H, H & H ), 6.6 (s, H ), 6.9 (m, 3H, H , H ), 7.45 (m,
3
2
3’’
5’’
8’
6’
4’
1
3
1
1
1
H,), 7.6 (m, H
5
), 7.8 (s, NH). C NMR (DMSOꢀd
6
) δ: 55.0 (OꢀC), 58.3 (OꢀC), 64.8 (C
2
5
),
),
01.5 (C
27.8 (C2’’& C6’’), 128.5 (C
8 6
), 107.6 (C ), 114.0 (C4a), 115.3 (C3’’& C5’’), 119.9 (C4’), 124.8 (C1’’), 125.7 (C
4
), 139.5 (C2’& C
3
), 140.0 (C5’), 154.5 (C8a), 160.3 (C4’’), 160.4
ꢀ1
+
(C
7
); IR (KBr, Cm ): 3003 (NꢀH), 1570 (C=N); MS (ESI, m/z): 334.96 [M+1] .
4.10.22.3-(2-(7-Methoxy-2-H-chromen-3-yl)-1-H-imidazol-5-yl)pyridine(15i).
1
Brown solid; yield 50%; mp.240ꢀ245 °C. H NMR (DMSOꢀd ) δ: 3.78 (s, OCH ), 5.2 (s,
6
3
OCH
.95 (s, H
NMR (DMSOꢀd
2
), 6.8 (d, J = 6.0 Hz, H
), 8.15 (d, J = 8 Hz, H6’’), 8.45 (d, J = 3.2 Hz, H4’’), 9.1 (s, H2’’), 12.8 (s, NH). C
) δ: 56.1 (OꢀC), 65.0 (C ), 113.5 (C ), 119.6(C4a), 119.8 (C ), 121.9 (C4’),
8 5 6
), 6.85 (m, 2H, H & H ), 7.19 (s, H4’), 7.4 (t, J = 6.0 Hz, H5’’’),
13
7
4
6
2
8
5

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1
23.4 (C
6
), 124.1 (C5’’), 128.0 (C
4
3 5
), 133.0 (C4’’), 136.0 (C & C2’), 131.8 (C3’’), 142.6 (C ),
ꢀ1
1
7
44.4 (C6’’), 146.3 (C8a), 147.8 (C2’’), 148.0 (C ); IR (KBr, Cm ): 3085 (NꢀH), 1581 (C=N);
+
MS (ESI, m/z): 306 ([M+1] .
4.10.23. 2-(7-Methoxy-2-H-chromen-3-yl)-5-(thiophen-2-yl)-1-H-imidazole (15j).
1
Brown solid; yield 40%; mp.120ꢀ124 °C. H NMR (DMSOꢀd ) δ: 3.75 (s, OCH ), 5.14 (s,
6
3
OCH
2
), 6.49 (s, H4’), 6.54 (dd, J = 8.4, 2.4 Hz, H
8
), 7.04 (t, J = 4.0, 4.4 Hz, H4’’), 7.09 (s, H
4
), 7.12 (d, J = 4.8 Hz, H
6
), 7.29 (d, J = 2.8 Hz, H3’’), 7.35 (d, J = 4.8 Hz, H
5
), 7.63 (d, J = 1.6
1
3
Hz, H5’’),12.6 (s, NH). C NMR (DMSOꢀd
6
) δ: 55.2 (OꢀC), 64.7 (C
2
), 101.5 (C
8
), 107.7 (C
6
),
),
1
1
13.7 (C4a), 119.0 (C4’), 121.3 (C5’), 123.2 (C5’’), 127.5 (C & C3’’), 127.9 (C4’’), 136.3 (C
5
3
ꢀ1
38.3 (C2’’), 143.3 (C2’), 154.5 (C8a), 160.4 (C
7
); IR (KBr, Cm ): 3111 (NꢀH), 1604 (C=N);
+
+
+
MS (ESI, m/z): 311.01 [M+1] , 312.16 [M+2] , 313.06 [M+3] .
4.10.24. 2-(5-Methoxy-2H-chromen-3-yl)-5-phenyl-1H-imidazole (16a).
1
White solid; yield 60%; mp.165ꢀ170 °C. H NMR (CDCl
3
) δ: 3.86 (s, OCH
3
), 5.28 (s,
OCH ), 6.47 (d, J = 8.4 Hz, H ), 6.54 (d, J = 8.4 Hz, H ), 7.1 (t, J = 8.4 Hz, H ), 7.17 (s, H ),
2
8
6
7
4’
4
7.26 (s, H ), 7.28 (d, J = 7.2 Hz, 2H, H2’’& H6’’), 7.38 (dd, J = 8.0, 15.4 Hz, 3H, H3’’’, H4’’’&
1
3
H
6 3 2 8 6
5’’’), 7.69 (s, NH). C NMR (DMSOꢀd ) δ: 56.1 (OCH ), 64.8 (C ), 104.6 (C ), 108.9 (C ),
7
112.1 (C4a), 114.1 (C4’), 121.6 (C2’’& C6’’), 124.8 (C4’’), 129.7 (C1’’), 128.9 (C , C3’’& C5’’),
ꢀ1
134.8 (C
3
5
& C2’), 144.2 (C5’), 154.4 (C8a), 155.8 (C ); IR (KBr, Cm ): 3134 (NꢀH), 1584
+
(
C=N); MS (ESI, m/z): 305.13 [M+1] .
4.10.25. 5-(4-Chlorophenyl)-2-(5-methoxy-2H-chromen-3-yl)-1H-imidazole (16b).
1
Yellow solid; yield 60%; mp.170ꢀ174 °C. H NMR (CDCl
3
) δ: 3.85 (s, OCH
3
), 5.27 (s,
), 7.16 (s,
), 7.33 (m, 4H, H2’’, H3’’, H5’’& H6’’), 7.7 (s, NH). C NMR (DMSOꢀd ) δ:
OCH
2
), 6.47 (d, J = 8.4 Hz, H
8
), 6.54 (d, J = 8.0 Hz, H
6
), 7.11 (t, J = 8.4, 8.0 Hz, H
7
13
H
4’), 7.26 (s, H
4
6

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5
5.7 (OCH
28.8 (C
8a), 155.6 (C
3
), 64.8 (C
2
), 103.6 (C
8
), 108.9 (C
6
), 111.6 (C4a), 114.9 (C4’), 126.1 (C2’’& C6’’),
1
4
, C3’’& C5’’), 129.7 (C1’’& C
7
3
), 132.5 (C4’’), 132.6 (C & C2’), 144.8 (C5’), 154.7
ꢀ1
+
(C
5
); IR (KBr, Cm ): 3015 (NꢀH), 1582 (C=N); MS (ESI, m/z): 339.08 [M+1] ,
+
3
41.11 [M+2] .
4.10.26. 5-(2,4-Dichlorophenyl)-2-(5-methoxy-2H-chromen-3-yl)-1H-imidazole (16c).
1
Off white solid; yield 55%; mp.190ꢀ195 °C. HNMR (CDCl
3
) δ: 3.87(s, OCH
), 7.12 (t, J = 8.4, 8.0 Hz, H
), 7.29 (d, J = 2.0 Hz, H5’’), 7.32 (d, J = 2.0 Hz, H3’’), 7.44 (d, J = 2.0 Hz,
3
), 5.27 (s,
OCH
2
), 6.48 (d, J = 7.6 Hz, H
4’), 7.26 (s, H
6’’), 7.71 (s, NH). C NMR (DMSOꢀd
), 129.8 (C ), 130.1 (C6’’), 130.7 (C3’’), 130.8 (C2’’), 131.4 (C4’’),
8
), 6.55 (d, J = 8.0 Hz, H
6
7
), 7.18 (s,
H
H
4
13
6
3 2 8 6
) δ: 56.1 (OCH ), 64.7 (C ), 104.7 (C ), 108.9 (C ),
114.9 (C4’), 127.8 (C1’’& C
4
7
ꢀ1
136.4 (C
3
& C2’), 143.8 (C5’), 154.5 (C8a), 155.9 (C
5
); IR (KBr, Cm ): 3013 (NꢀH), 1583
+
+
(
C=N); MS (ESI, m/z): 373.06 [M+1] , 375.02 [M+2] .
4.10.27. 2-(5-Methoxy-2H-chromen-3-yl)-5-(3-nitrophenyl)-1H-imidazole (16d).
1
Orange solid; yield 55%; mp.245ꢀ250 °C. H NMR (DMSOꢀd ) δ: 3.86 (s, OCH ), 5.18 (s,
6
3
OCH
2
), 6.52 (d, J = 8.0 Hz, H
8 6 7
), 6.64 (d, J = 8.0 Hz, H ), 7.14 (t, J = 8.4, 8.0 Hz, H ) 7.44 (s,
H
H
4
), 7.66 (t, J = 8.0 Hz, H5’’), 8.03 (s, H4’), 8.05 (d, J = 7.2 Hz, H6’’), 8.25 (d, J = 7.6 Hz,
1
3
4’’),8.6 (s, H2’’),12.9 (s, NH). C NMR (DMSOꢀd
6
) δ: 55.6 (OCH
3
), 64.2 (C
2
), 104.2 (C
8
),
),
108.4 (C
6
), 111.4 (C4a), 114.3 (C4’), 118.2 (C2’’), 120.6 (C4’’), 120.8 (C5’’), 129.5 (C
7
& C
4
1
30.0 (C ), 130.4 (C ), 136.1 (C ), 138.6 (C ), 142.2 (C ), 148.3 (C ), 153.9 (C ), 155.9
6
’’
1’’
2’
3
5’
3’’
8a
ꢀ1
+
(
C ); IR (KBr, Cm ): 3092 (NꢀH), 1580 (C=N); MS (ESI, m/z): 350.1 [M+1] .
5
4.10.28. 5-(4-Bromophenyl)-2-(5-methoxy-2H-chromen-3-yl)-1H-imidazole (16e).
1
Off white solid; yield 60%; mp.195ꢀ200 °C. H NMR (CDCl
3
) δ: 3.85 (s, OCH
3
), 5.26 (s,
OCH
2
), 6.47 (d, J = 8.4 Hz, H
8
), 6.54 (d, J = 8.0 Hz, H
6
), 7.11 (t, J = 8.4, 8.0 Hz, H ), 7.17 (s,
7

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1
3
H4
’
), 7.33 (s, H
DMSOꢀd ) δ: 55.7 (OCH
4’’), 126.4 (C
C ), 155.6 (C ), 154.7 (C ); IR (KBr, Cm ): 3135 (NꢀH), 1583 (C=N); MS (ESI, m/z):
4
), 7.49 (d, J = 8.0 Hz, 4H, H2’’, H3’’, H5’’& H6’’), 7.62 (s, NH). C NMR
), 64.8 (C ), 103.6 (C ), 109.0 (C ), 111.6 (C4a), 114.9 (C4’), 120.6
& C1’’), 131.8 (C3’’& C5’’), 137.0 (C2’& C ), 144.8
(
6
3
2
8
6
(C
4
, C2’’& C6’’), 129.8 (C
7
3
ꢀ1
(
5
’
8a
5
+
+
3
85.02 [M+1] , 386.02 [M+2] .
4.10.29. 5-(4-(Benzyloxy)phenyl)-2-(5-methoxy-2H-chromen-3-yl)-1H-imidazole (16f).
1
Pale green solid; yield 54%; mp.175ꢀ180 °C. H NMR (CDCl
3
) δ: 3.86(s, OCH
), 6.54 (d, J = 8.0Hz, H
), 7.14 (s, H ), 7.25 (s, H ), 7.34 (d, J =
3
), 5.09 (s,
OCH
2
), 5.27 (d, J = 0.8 Hz, BnꢀOCH
2
), 6.47 (d, J = 8.4 Hz, H
8
6
), 7.02
(
d, J = 8.8 Hz, 2H, H3’’& H5’’) 7.1 (t, J = 8.4 Hz, H
7
4
4
7.2 Hz, 2H, H2’’’& H6’’’), 7.39 (t, J = 6.8, 7.6 Hz, 3H, H3’’’, H4’’’& H5’’’), 7.44 (d, J = 7.2 Hz,
1
3
H
2’’& H6’’), 7.6 (s, NH). C NMR (CDCl
), 108.9 (C ), 111.7 (C4a), 114.3 (C3’’& C5’’), 115.2 (C4’), 120.7 (C1’’), 126.2 (C2’’’& C6’’’),
27.5 (C4’’’), 128.0 (C2’’& C6’’), 128.6 (C , C3’’’& C5’’’), 129.5 (C & C2’), 143.7
3 2
); δ 55.6 (OCH3), 64.9 (C ), 70.1 (BnꢀOꢀC), 103.6
(C
8
6
1
4
7 3
), 136.9 (C
ꢀ1
(
C ), 144.3 (C ), 154.7 (C ), 155.6 (C ), 158.1 (C ); IR (KBr, Cm ): 3072 (NꢀH), 1580
5’ 1’’’ 8a 5 4’’
+
(
C=N); MS (ESI, m/z): 411.14 [M+1] .
36
5
.0 Biological Assay :
5.1 Angiogenesis Assay:
Human clonal endothelial colony forming cells (ECFC, Engenator) were cultured in
EGM‐2MV media containing 10% FBS (EGM‐2MV+FBS). ECFCs were expanded to
2
passage 7, rapidly frozen and stored in liquid N until further use. Human adipose derived
stem cells (ADSC, Zen Bio) were derived from pooled donor samples, cultured in
EGM‐2MV+FBS, rapidly frozen and stored over liquid N until further use.On day1, ECFCs
2
were quickly thawed, diluted into pre‐warmed EGM‐2 media containing 10% FBS
(EGM‐2+FBS), and incubated for 24 hours. ECFCs were washed with PBS, trypsinized and

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replated withEGM‐2+FBS for 48 hours. On third day, ADSCs were quickly thawed and
diluted into pre‐warmed EGM‐2MV+FBS. The ADSCs were collected by centrifugation and
suspended in Optimized Media (TCS Cell works). ADSCs (5000/well) were added to a 384
well Cell Bind plate (Corning), incubated at room temperature for 5 minutes, and then placed
2
in a CO incubator overnight. On fourth day, ECFC cultures from Day 2 were washed with
PBS, trypsinized and resuspendedwithEGM‐2+FBS. Cells were collected by centrifugation,
suspended in Optimized Media and passed through a sterile 23 gauge needle. ECFCs (500
/
well) were overlaid onto the ADSC feeder layer from Day 3 and returned to the CO2
incubator. After 2 hours, rhVEGF (10 ng/ml; R&D Systems) and compounds at the indicated
concentrations were added (0.5% (v/v) DMSO final) and incubated for 96 hours. Maximum
and minimum responses correspond to rhVEGF +0.5% (v/v) DMSO orrhVEGF + 500
nMsutent (Sunitinib), respectively.
5.2 Endothelial and Nuclear Staining:
Co‐cultures were fixed with 3.7% formaldehyde‐PBS for 20 minutes, treated with 0.1%
TX‐100‐PBS for 20 minutes, washed twice with PBS, and incubated with 63 ng/ml mouse
Anti‐Human CD31 antibody (BD Pharmigen, 550389) in PBS containing 1% BSA at 4°C
overnight. Following PBS wash, samples were then incubated with 3ug/ml Alexa 488 goat
secondary antibody in PBS for 1 hr and then washed twice with PBS before staining cellular
DNA with Hoechst stain (2 ug/ml).
5.3 Cellular Imaging:
Fixed and stained ECFC‐ADSC co‐cultures were analyzed with an Array Scan VTI (Thermo
Scientific) using a 5x objective and collecting 4, non‐adjacent frames per well; nuclei and
CD31 were visualized using the XF93‐Hoechst and XF93‐Alexa‐488 dichroic mirror
emission filter pairs, respectively. Endothelial tube features were determined with the
Cellomics Tube Formation V3 application by analysis of the CD31 channel. Relative cell

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death in the ECFC‐ADSC co‐culture was measured by loss of valid nuclear objects as
determined by the Target Activation V3 applications.
6.0 Molecular Docking Studies:
With a view to find a correlation between the antiꢀangiogenesis activity of 5ꢀ(substituted
aryl)ꢀ2ꢀ(5methoxyꢀ2Hꢀchromenꢀ3ꢀyl)ꢀ1Hꢀimidazoles (16a-f, 15h, 14f, h, j, 13f, g, I, j )and
theirbinding with target proteins viz; KRAS, Wnt and VEGF,the docking studies were
3
7,38
carried out employing AutoDocksoftware.
The receptorꢀligand interactions and the
corresponding interaction energies were identified after the docking studies.
39ꢀ43
Since Human KRAS protein is a target in antiꢀangiogenesis
, we have selected the
crystal structure of Human KRASreceptor protein with PDB ID: (4EPX.pdb) from protein
44
data bank. Docking studies were performed with fourteen molecules (16a-f, 15h, 14f, h, j,
3f, g, i, j) to investigate the receptor interactions. All the fourteen molecules were
constructed using the tools of SYBYL software2 and the structures were minimized using
00 steps of steepest descent followed by 500 steps of conjugate gradient methods and
1
5
structure was stabilized at 1100 steps. Later binding / catalytic sites of protein 4EPX.pdb
were identified using biopolymer module of the SYBYLꢀX (Tripos) software.
4
5
Further, the molecules were loaded into the AutoDock software , and converted into
pdb structures by applying the charge assigning methodof Kolman and Gasteiger Huckle and
saved into a pdbqt form. Later, polar atoms are added to protein and protein structure was
kept in grid Nꢀdimension (Grid sizes for receptor X = 11.393, Y = 1.498, Z = 9.595; ligand X
=
40, Y = 36, Z = 38) for fourteen molecules. Virtual screening studies were performed using
AutoDock 4.0 software to predict interactions based on Genetic and Lamarckian