Medicinal Chemistry Research
1555, 1451 (Ar–C=C), 1131 (Ar–C–H); 1H-NMR (DMSO-
d6, 500 MHz) δ ppm 7.94–7.93 (d, 2H, H-2′, H-6′),
7.86–7.84 (d, t, 3H, H-2, H-6, H-4), 7.44 (d, t, d, 4H, H-α,
H-3, H-5, H-β), 6.64–6.63 (d, 2H, H-3′, H-5′), 6.17 (s, 2H,
NH2). HPLC % purity = 99.18%.
1-(4ʹ-Amino-phenyl)-3-(3-nitro-phenyl)-prop-2en-1-one
(C7) Orange solid, yield (68%), m.p. 165–168 °C. IR
(KBr) νmax in cm−1: 3425, 3335 (NH2), 1632 (C=O), 1609
(C=C), 1530, 1344 (NO2); 1H-NMR (DMSO-d6,
500 MHz) δ ppm 8.69 (s, 1H, H-2), 8.30–8.29 (d, 1H, H-4),
8.25–8.23 (d, 1H, H-6), 8.07–8.04 (d, 1H, H-β, J = 16 Hz),
7.98–7.97 (d, 2H, H-2′, H-6′), 7.76–7.71 (m, 2H, H-5, H-α,
J = 16 Hz), 6.68–6.66 (d, 2H, H-3′, H-5′), 6.17 (s, 2H,
NH2). HPLC % purity = 98.14%.
1-(4ʹ-Amino-phenyl)-3-(2-chloro-phenyl)-prop-2en-1-one
(C2) Yellow solid, yield (78%), m.p. 106–109 °C. IR
(KBr) νmax in cm−1: 3306, 3231 (NH2), 1643 (C=O), 1608
1
(C=C), 1178 (Ar–Cl); H-NMR (DMSO-d6, 500 MHz) δ
ppm 8.17–8.15 (d, 1H, H-6), 7.97–7.88 (m, 4H, H-β, J =
15.5 Hz, H-2′, H-6′, H-α, J = 15.5 Hz), 7.57–7.56 (d, 1H,
H-3), 7.48–7.45 (m, 2H, H-4, H-5), 6.68–6.67 (d, 2H, H-3′,
H-5′), 6.17 (s, 2H, NH2). HPLC % purity = 96.65%.
1-(4ʹ-Amino-phenyl)-3-(4-nitro-phenyl)-prop-2en-1-one
(C8) Orange solid, yield (60%), m.p. 182–184 °C. IR
(KBr) νmax in cm−1: 3459, 3338 (NH2), 1646 (C=O), 1615
(C=C), 1545, 1344 (NO2); 1H-NMR (DMSO-d6,
500 MHz) δ ppm 8.28–8.27 (d, 2H, H-3, H-5), 8.13–8.11
(d, 2H, H-2, H-6), 8.06–8.03 (d, 1H, H-β, J = 16 Hz),
7.97–7.95 (d, 2H, H-2′, H-6′), 7.71–7.68 (d, 1H, H-α, J =
16 Hz), 6.67–6.66 (d, 2H, H-3′, H-5′), 6.16 (s, 2H, NH2).
HPLC % purity = 98.99%.
1-(4ʹ-Amino-phenyl)-3-(4-chloro-phenyl)-prop-2en-1-one
(C3) Yellow solid, yield (80%), m.p. 157–159 °C. IR
(KBr) νmax in cm−1: 3459, 3341 (NH2), 1630 (C=O), 1602
1
(C=C), 1175 (Ar–Cl); H-NMR (DMSO-d6, 500 MHz) δ
ppm 7.94–7.92 (d, 2H, H-2, H-6), 7.88–7.85 (m, 3H, H-2′,
H-6′, H-β, J = 16 Hz), 7.62–7.59 (d, 1H, H-α, J = 16 Hz),
7.52–7.50 (d, 2H, H-3, H-5), 6.66–6.65 (d, 2H, H-3′, H-5′),
6.08 (s, 2H, NH2). HPLC % purity = 98.31%.
1-(4ʹ-Amino-phenyl)-3-(3-hydroxy-phenyl)-prop-2en-1-one
(C9) Yellow powder, yield (62%), m.p. 203–208 °C. IR
(KBr) νmax in cm−1: 3343 (NH2), 3231 (OH), 1644 (C=O),
1582, 1557 (C=C alkene), 1439 (Ar–C=C), 1132
1
1-(4ʹ-Amino-phenyl)-3-(2-methoxy-phenyl)-prop-2en-1-one
(C4) Yellow powder, yield (83%), m.p.128 °C. IR (KBr)
νmax in cm−1: 3335, 3217 (NH2), 1243, 1022 (OCH3),
1644 (C=O, α, β-unsaturated), 1593 (C=C alkene), 1521
(Ar–C=C), 1172 (Ar–C–H); 1H-NMR (DMSO-d6,
500 MHz) δ ppm 3.9 (s, OCH3-2), 6.15 (s, NH2-4′),
6.62–6.64 (d, H-3′, H-5′), 7.01-7.04 (d, H-α, t, H-5),
7.10–7.12 (d, H-3), 7.41–7.44 (t, H-4), 7.80–7.83 (d, H-β),
7.90–7.94 (d, H-6, H-2′, H-6′). HPLC % purity = 96.67%.
(Ar–C–H); H-NMR (DMSO-d6, 500 MHz) δ ppm 9.58 (s,
1H, OH-3), 7.91–7.89 (d, 2H, H-2′, H-6′), 7.76–7.73 (d,
1H, H-α), 7.53–7.50 (d, 1H, H-β), 7.26–7.21 (t, d, 2H, H-5,
H-6), 7.17 (s, 1H, H-2), 6.84–6.83 (d, 1H, H-4), 6.63–6.61
(d, 2H, H-3′, H-5′), 6.15 (s, 2H, NH2). HPLC % purity =
92.28%.
1-(4ʹ-Amino-phenyl)-3-(4-hydroxy-phenyl)-prop-2en-1-one
(C10) Yellow powder, yield (58%), m.p. 173 °C. IR (KBr)
νmax in cm−1: 3335 (NH2), 3214 (OH), 1635 (C=O), 1625,
1588 (C=C alkene), 1507 (Ar–C=C), 1163 (Ar–C–H); 1H-
NMR (DMSO-d6, 500 MHz) δ ppm 9.80 (s, 1H, OH-4),
8.20–8.19 (d, 2H, H-3, H-5), 7.91–7.90 (d, 1H, H-α),
7.57–7.54 (d, 2H, H-2′, H-6′), 6.9–6.8 (d, 2H, H-2, H-6),
6.63–6.61 (d, 1H, H-β), 6.58–6.56 (d, 2H, H-3′, H-5′), 6.2
(s, 2H, NH2). HPLC % purity = 98.98%.
1-(4ʹ-Amino-phenyl)-3-(3-methoxy-phenyl)-prop-2en-1-one
(C5) Brown powder, yield (75%), m.p. 145–146 °C. IR
(KBr) νmax in cm−1: 3341, 3218 (NH2), 1222, 1024
(OCH3), 1649 (C=O, α, β-unsaturated), 1582 (C=C
alkene), 1520 (Ar–C=C), 1171 (Ar–C-H); 1H-NMR
(DMSO-d6, 500 MHz) δ ppm 3.85 (s, OCH3-3), 6.06 (s,
NH2-4′), 6.66 (d, H-3′, H-5′), 7.01 (d, H-4), 7.35-7.39 (t, H-
5, d, H-6), 7.42 (s, H-2), 7.58–7.61 (d, H-α), 7.82–7.85 (d,
H-β), 7.94 (d, H-2′, H-6′).). HPLC % purity = 99.36%.
Synthesis of linkages of cinnamic acid (Lik1–Lik10)
Linkages of cinnamic acid with 4-aminoacetophenone and
substituted 4-amino chalcone were synthesized as shown in
Scheme 3. Cinnamic acid (10 mmol) was dissolved in 20 ml
of dimethylformamide (DMF), followed by addition of
triethanolamine (10 mmol). The solution was cooled in an
ice bath, and 10 mmol of amine (4-aminoacetophenone or
substituted 4-amino chalcone) was added. Then, a solution
comprising of 10 mmol of N, N′-dicyclohexylcarbodiimide
in 20 ml of dichloromethane was added in the reaction
mixture. The mixture was stirred at 0 °C for 30 min and then
1-(4ʹ-Amino-phenyl)-3-(4-methoxy-phenyl)-prop-2en-1-one
(C6) Yellow solid, yield (88%), m.p. 108–111 °C. IR
(KBr) νmax in cm−1: 3457, 3331 (NH2), 1630 (C=O), 1599
(C=C), 1259, 1025 (C–O–C); 1H-NMR (DMSO-d6,
500 MHz) δ ppm 7.91–7.90 (d, 2H, H-2′, H-6′), 7.79–7.78
(d, 2H, H-2, H-6), 7.72–7.69 (d, 1H, H-β, J = 15.5 Hz),
7.61–7.58 (d, 1H, H-α, J = 15.5 Hz), 7.02–7.01(d, 2H, H-3,
H-5), 6.65–6.64 (d, 2H, H-3′, H-5′), 6.01 (s, 2H, NH2), 3.86
(s, 3H, OCH3). HPLC % purity = 97.55%.