SAIDUGARI et al., Orient. J. Chem., Vol. 32(4), 2155-2161 (2016)
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evaporated and the obtained residue was diluted
with ethylacetate (25 mL). The organic layer was
washed with aqueous saturated NaHCO3 (3 X 15
mL) followed by water (2 X 15 mL) and brine solution
(20 mL).The organic layer was separated, dried over
sodium sulphate, filtered and evaporated to obtain
respective ethyl benzoates.
2H), 7.96-7.80 (m, 5H), 7.15 (brs, 1H), 6.86 (d, J =
10.6 Hz, 2H), 5.72 (s, 2H), 3.90 (s, 3H), 3.80 (s, 3H);
ESI- MS: m/z, 459.0 (M+1).
(E)-N’-(4-(1-((3,4-dimethoxypyridin-2-yl)
methyl)-1H-1,2,3-triazol-4-yl)benzylidene)-4-
methoxybenzohydrazide 8c
Off white solid;Yield:84%;M.p.:96–97°C;IR
To the above prepared respective ethyl
benzoates (6.65 mmol) in ethanol was added
hydrazine-hydrate (40.0 mmol) and refluxed for 8 h.
Ethanol was evaporated from the reaction mixture
and the precipitated solids were slurred with pet-
ether (5 times) and filtered at the pump and dried to
obtain benzohydrazides7a-7j.
(KBr): Umax 3570, 3527, 3453, 3409, 3366, 3288,
3158, 3093, 2939, 2836, 1647, 1603, 1539, 1498,
1456, 1426, 1355, 1302, 1256, 1179, 1143, 1109,
1068, 1025, 988, 915, 837, 760, 725, 689, 614, 567,
537, 509, 455 cm-1; 1H NMR (400 MHz, DMSO-d6):
d 11.78 (brs, 1H, -CONH), 8.72 (brs,1H), 8.48 (brs,
1H, -CH=N-), 8.13 (brs, 1H), 7.94-7.91 (m, 4H), 7.81
(brs, 2H), 7.23 (brs, 1H, triazole), 7.07 (d, J = 10.4
Hz, 2H, ), 5.72 (brs, 2H), 3.91 (s, 3H), 3.84 (s, 3H),
3.81 (s, 3H); ESI- MS: m/z, 443.0(M+1).
General procedure for the synthesis of hydrazone
derivatives 8a-8j
To a solution of compound 6 (100 mg,
0.308 mmol) in ethanol was added corresponding
benzohydrazides 7a-7j (0.308 mmol) and heated to
reflux for 30 min.The precipitated solids were filtered
at the pump and dried to afford hydrazone derivatives
8a-8j in quantitative yields.
(E)-N’-(4-(1-((3,4-dimethoxypyridin-2-yl)
methyl)-1H-1,2,3-triazol-4-yl)benzylidene)-4-
(methylsulfonyl)benzohydrazide 8d
Yellow solid;Yield: 82%; M.p.: 134–135°C;
IR (KBr): Umax 3570, 3527, 3453, 3409, 3366, 3288,
3158, 3093, 2939, 2836, 1647, 1603, 1539, 1498,
1456, 1426, 1355, 1302, 1256, 1179, 1143, 1109,
1068, 1025, 988, 915, 837, 760, 725, 689, 614, 567,
(E)-N’-(4-(1-((3,4-dimethoxypyridin-2-yl)
methyl)-1H-1,2,3-triazol-4-yl)benzylidene)
benzohydrazide 8a
1
537, 509, 455 cm-1; H NMR (400 MHz, DMSO-
Pale yellow solid; Yield: 90%; M.p.: 101–
d6): d 12.11 (brs, 1H), 8.67 (brs,1H), 8.48 (s, 1H),
8.17-8.02 (m, 5H), 7.97 (d, J = 10.8 Hz, 2H), 7.89
(d, J = 10.8 Hz, 2H), 7.15 (brs, 1H), 5.72 (brs, 2H),
3.90 (s, 3H), 3.80 (s, 3H), 3.30 (s, 3H); ESI- MS:
m/z, 521.0 (M+1).
102°C;IR (KBr):Umax 3425, 3260, 3138, 3057, 3023,
2974, 2944, 2842, 1655, 1584, 1538, 1489, 1456,
1426, 1358, 1299, 1278, 1228, 1177, 1139, 1101,
1066, 997, 972, 947, 914, 821, 804, 762, 718, 626,
534, 493 cm-1;1H NMR (400 MHz, DMSO-d6): d 11.89
(brs, 1H), 8.66 (s, 1H), 8.44 (s, 1H), 8.13 (brs, 1H),
7.99-7.92 (m, 4H), 7.80 (d, J = 10.8 Hz, 2H), 7.63-
7.52 (m, 3H), 7.16 (brs, 1H), 5.72 (brs, 2H), 3.91 (s,
3H), 3.81 (s, 3H); ESI -MS: m/z, 443.0 (M+1).
(E)-N’-(4-(1-((3,4-dimethoxypyridin-2-yl)
methyl)-1H-1,2,3-triazol-4-yl)benzylidene)-3,4,5-
trimethoxybenzohydrazide 8e
Pale yellow solid; Yield: 84%; M.p.: 89–
90°C;1H NMR (400 MHz, DMSO-d6): d 11.74 (brs,
1H), 8.65 (s,1H), 8.48 (s, 1H), 7.96 (d, J = 10.8 Hz,
2H), 7.80 (d, J = 10.8 Hz, 2H), 7.24 (s, 2H), 5.72 (brs,
2H), 3.90 (s, 3H), 3.89 (s, 3H); ESI MS: m/z, 533.0
(M+1).
(E)-N’-(4-(1-((3,4-dimethoxypyridin-2-yl)
methyl)-1H-1,2,3-triazol-4-yl)benzylidene)-4-
hydroxybenzohydrazide 8b
Pale yellow solid; Yield: 88%; M.p.: 128–
129°C;IR (KBr):Umax 3270, 3147, 3020, 2944, 2837,
2792, 2672, 2601, 1907, 1645, 1607, 1588, 1542,
1508, 1492, 1450, 1358, 1301, 1281, 1237, 1173,
1143, 1105, 1072, 995, 972, 951, 912, 838, 809,
761, 721, 685, 622, 598, 507 cm-1;1H NMR (400
MHz, DMSO-d6): d 11.68 (brs, 1H), 10.13 (brs, 1H),
8.66 (brs, 1H), 8.44 (brs, 1H), 8.10 (d, J = 9.6 Hz,
(E)-N’-(4-(1-((3,4-dimethoxypyridin-2-yl)
methyl)-1H-1,2,3-triazol-4-yl)benzylidene)-3-
nitrobenzohydrazide 8f
Yellow solid; Yield: 92%; M.p.: 84–85°C;
1H NMR (400 MHz, DMSO-d6): d 11.20 (brs, 1H),
10.16 (brs, 1H), 8.77 (brs,1H), 8.60 (brs, 1H), 8.44