Synthetic Organic Chemistry
J. Chin. Chem. Soc., Vol. 54, No. 3, 2007 1009
H, 3.80; N, 10.9. Found: C, 55.82; H, 3.35; N, 10.62.
Other compounds 4b-j were prepared in a similar
way using 3b-j; characterization data are respectively pre-
sented in Table 1.
(C=O, cyclic), 1450 (CH2), 723 (C-S-C); 1H NMR d: 9.16
(s, 1H, NH), 7.38-7.89 (m, 8H, Ar-H), 4.59 (s, 2H, CH2),
4.62 (s, 2H, CH2, cyclic), 3.96 (s, 3H, OCH3), 3.26 (s, 1H,
N-CH-Ar).
[(5-Benzylidene)-2-aryl-4-oxo-1,3-thiazolidinhydrazino-
acetyl]-mercaptobenzoxazole 5a
[(5-Arylidene-2-chlorophenyl-4-oxo-1,3-thiazolidin)-
hydrazinoacetyl-mercaptobenzoxazole] (5b)
An equimolar solution of 4a (0.0002 mole) and benz-
aldehyde (0.0002 mole) in methanol (25 mL) was kept at
room temperature for about 24 hours. The solvent was re-
moved in vacuo and the residue was dried and recrystal-
lised from ethanol to afford pure material: 61% of yield, mp
185-187 °C; IR (KBr) vmax cm-1: 3342, 1590, 1545, 1239,
1040, 650 (benzoxazole nucleus with aromatic ring), 3348,
1342 (-NH), 2980 (N-CH-S), 1450 (CH2), 1715 (C=O cy-
clic), 1630 (> C=CH Ar), 721 (C-S-C); 1H NMR d 9.15 (s,
1H, NH), 7.04-7.96 (m, 14H, Ar-H), 5.15 (s, 1H > C=
CHAr), 4.48 (s, 2H, CH2) 3.20 (s, 1H, N-CH Ar). FAB-MS,
m/z: 473 [M]+, 445, 384, 343, 327, 295, 281, 267, 253, 207,
192, 178, 164, 162, 150, 136, 129, 122, 118, 108, 92, 90, 79,
66. The proposed mass fragmentation is cited in Chart 1.
Anal. Calcd for C25H19N3O3S2: C, 63.4; H, 4.0; N, 8.80.
Found: C, 63.3; H, 3.82; N, 8.52.
IR (KBr) vmax cm-1: 3340, 1592, 1550, 1239, 1042,
652 (benzoxazole nucleus with aromatic ring), 3350, 1345
(-NH), 2982 (N-CH-S), 1440 (CH2), 1718 (C=O, cyclic),
1632 (> C=CH Ar), 750 (Ar-Cl), 721 (C-S-C); 1H NMR d:
9.10 (s, 1H, NH), 7.00-7.92 (m, 13H, Ar-H), 5.12 (s, 1H, >
C=CH Ar), 4.51 (s, 2H, CH2), 325 (s, 1H, N-CH-Ar).
[(5-Arylidene-2-nitrophenyl-4-oxo-1,3-thiazolidin)-
hydrazinoacetyl-mercaptobenzoxazole] (5c)
IR (KBr) vmax cm-1: 3329, 1588, 1560, 1232, 1050,
660 (benzoxazole nucleus with aromatic ring), 3062, 1350
(-NH), 2988 (N-CH-S), 1490, 1350 (Ar-NO2), 1450 (CH2),
1721 (> C=O, cyclic), 1635 (> =CHAr), 718 (C-S-C); 1H
NMR d: 8.95 (s, 1H, -NH), 7.59-7.90 (m, 13H, Ar-H), 5.13
(s, 1H, > C=CH Ar), 4.55 (s, 2H, CH2), 3.29 (s, 1H, N-
CH-Ar).
[2-(2-Chlorophenyl-4-oxo-1,3-thiazolidin)-hydrazino-
acetyl-mercaptobenzoxazole] (4b)
[(5-Arylidene-2-methoxyphenyl-4-oxo-1,3-thiazolidin)-
hydrazinoacetyl-mercaptobenzoxazole] (5h)
IR (KBr) vmax cm-1: 3032, 1585, 1557, 1248, 1040,
645 (benzoxazole nucleus with aromatic ring) 3342, 1330
(-NH-), 2988 (N-CH-S), 1720 (C=O, cyclic), 1424 (CH2),
756 (Ar-Cl), 716 (C-S-C); 1H NMR d: 9.12 (s, 1H, NH),
7.02-7.90 (m, 8H, Ar + H), 4.55 (s, 2H, CH2), 4.50 (s, 2H,
CH2, cyclic), 3.17 (s, 1H, CH-Ar).
IR (KBr) vmax cm-1: 3320, 1590, 1564, 1237, 1047,
652 (benoxazole nucleus with aromatic ring) 3066, 1352
(-NH), 2983 (N-CH-S), 1453 (CH2), 1716 (> C=O, cyclic),
1632 (> C=CH Ar), 2872, 1162 (Ar-OCH3), 721 (C-S-C);
1H NMR d: 9.02 (s, 1H, NH), 7.58-7.92 (m, 13H, Ar-H),
5.09 (s, 1H, > C=CH Ar), 4.49 (s, 2H, CH2), 3.31 (s, 1H,
N-CH-Ar), 3.90 (s, 3H, OCH3).
[2-(2-Nitrophenyl-4-oxo-1,3-thiazolidin)-hydrazinoace-
tyl-mercaptobenzoxazole] (4c)
IR (KBr) vmax cm-1: 3035, 1577, 1562, 1237, 1048,
650 (benzoxazole nucleus with aromatic ring) 3420-1350
(-NH), 2985 (N-CH-5) 1712 (> C=O, cyclic), 1429 (CH2),
1495, 1345 (Ar-NO2), 720 (C-S-C); 1HNMR d: 9.14 (s, 1H,
NH), 7.32-7.82 (m, 8H, Ar-H), 4.52 (s, 2H, CH2), 4.49 (s,
2H, CH2 (cyclic), 3.20 (s, 1H, CH-Ar).
ACKNOWLEDGEMENTS
The authors are thankful to SAIF, CDRI, Lucknow,
for providing special and analytical data of the compounds.
Authors are also thankful to the Head of the Botany Depart-
ment and the Head of the Microbiology Department of Dr.
H. S. Gour University, Sagar, for giving cooperation for bi-
ological screening.
[2-(2-Methoxyphenyl-4-oxo-1,3-thiazolidin)-hydrazino-
acetyl-mercaptobenzoxazole] (4h)
IR (KBr) vmax cm-1: 3038, 1579, 1565, 1243, 1055,
642 (benzoxazole nucleus with aromatic ring), 3358, 1348
(-NH), 2867, 1172 (Ar-OCH3), 2992 (N-CH-S), 1715
Received June 6, 2006.