Microwave-Assisted Synthesis of Some 2,4-Thiazolidinedione Derivatives 155
(t, 2H), 4.31 (t, 2H), 7.12–7.38 (m, 8H, Ar-H), 7.59 (s,
DMSO-d6, δ ppm): 3.07 (t, 2H), 4.16 (t, 2H), 5.10 (br
s, 1H, NH), 6.72–7.14 (m, 8H, Ar-H), 7.71 (s, 1H,
vinylic-H), 10.12 (s, 2H, NH2), and 11.20 (br s, 1H,
NH); Anal.: Calcd. for C18H17N3O5S2 (419): N, 10.03;
S, 15.18; Found: N, 9.99; S, 15.17.
1H, thiazolyl-H), 7.91 (s, 1H, vinylic-H), 8.37 (br s,
1H, NH), and 11.58 (br s, 1H, NH); Anal.: Calcd. for
C21H16ClN3O3S2 (457.5): N, 9.18; S, 13.99; Found: N,
9.06; S, 13.79.
5-[4ꢀ-(4ꢀꢀ-Phenyl-(4ꢀꢀꢀ-chloro)-thiazol-2ꢀꢀ-yl-amino-
ethoxy)-3ꢀ-methoxybenzylidenyl]-2,4-thiazolidine-
dione (5h). IR (KBr, cm−1): 3425 (2NH), 3117 (CH
aromatic), 2974 and 2927 (CH aliphatic asymmetric
and symmetric stretching vibrations, respectively),
1688 and 1590 (2CO stretching vibrations), 1303
(CN), and 1254 (COC); 1H NMR (CDCl3 + DMSO-d6,
δ ppm): 3.17 (t, 2H), 3.9 (s, 3H), 4.41 (t, 2H), 7.20–
7.45 (m, 7H, Ar-H), 7.61 (s, 1H, thiazolyl-H), 7.94 (s,
1H, vinylic-H), 8.44 (br s, 1H, NH), and 11.67 (br s,
1H, NH); Anal.: Calcd. for C22H18ClN3O4S2 (487.5):
N, 8.62; S, 13.13; Found: N, 8.42; S, 13.01.
5-[4ꢀ-(4ꢀꢀ-Sulphonamidophenyl aminoethoxy)-3ꢀ-
methoxybenzylidenyl]-2,4-thiazolidinedione (6b). IR
(KBr, cm−1): 3461 (2NH and NH2), 3111 (CH aro-
matic), 2957 and 2931 (CH aliphatic asymmetric
and symmetric stretching vibrations, respectively),
1677 and 1551 (2CO stretching vibrations), 1421
(CN stretching), 1310 and 1140 (SO2 asymmetric
1
and symmetric), and 1258 (COC); H NMR (CDCl3
+ DMSO-d6, δ ppm): 3.12 (t, 2H), 3.82 (s, 3H), 4.22
(t, 2H), 5.23 (br s, 1H, NH), 6.8–7.34 (m, 7H, Ar-H),
7.83 (s, 1H, vinylic-H), 10.16 (s, 2H, NH2), and 11.22
(br s, 1H, NH); Anal.: Calcd. for C19H19N3O6S2 (449):
N, 9.36; S, 14.26; Found: N, 9.31; S, 14.19.
5-[4ꢀ-(4ꢀꢀ-Phenyl-(4ꢀꢀꢀ-chloro)-thiazol-2ꢀꢀ-yl-amino-
ethoxy)-3ꢀ,5ꢀ-dimethoxybenzylidenyl]-2,4-thiazolidi-
nedione (5i). IR (KBr, cm−1): 3435 (2NH), 3124 (CH
aromatic), 2972 and 2928 (CH aliphatic asymmetric
and symmetric stretching vibrations, respectively),
1679 and 1586 (2CO stretching vibrations), 1311
(CN), and 1252 (COC); 1H NMR (CDCl3 + DMSO-d6,
δ ppm): 3.2 (t, 2H), 3.99 (s, 6H), 4.47 (t, 2H), 7.25–
7.51 (m, 6H, Ar-H), 7.72 (s, 1H, thiazolyl-H), 7.91 (s,
1H, vinylic-H), 8.48 (br s, 1H, NH), and 11.71 (br s,
1H, NH); Anal.: Calcd. for C23H20ClN3O5S2 (517.5):
N, 8.12; S, 12.37; Found: N, 8.08; S, 12.39.
5-[4ꢀ-(4ꢀꢀ-Sulphonamidophenyl aminoethoxy)-3ꢀ,
5ꢀ-dimethoxybenzylidenyl]-2,4-thiazolidinedione (6c).
IR (KBr, cm−1): 3466 (2NH and NH2), 3120 (CH
aromatic), 2959 and 2938 (CH aliphatic asymmetric
and symmetric stretching vibrations, respectively),
1682 and 1556 (2CO stretching vibrations), 1425
(CN stretching), 1315 and 1147 (SO2 asymmetric
1
and symmetric), and 1260 (COC); H NMR (CDCl3
+ DMSO-d6, δ ppm): 3.21 (t, 2H), 3.91 (s, 6H), 4.35
(t, 2H), 5.36 (br s, 1H, NH), 6.95–7.48 (m, 6H, Ar-H),
7.87 (s, 1H, vinylic-H), 10.20 (s, 2H, NH2), and 11.25
(br s, 1H, NH); Anal.: Calcd. for C20H21N3O7S2 (479):
N, 8.77; S, 13.37; Found: N, 8.72; S, 13.30.
Synthesis of 5-[4ꢀ-(2ꢀꢀ/4ꢀꢀ-Sulphonamido-4ꢀꢀ-
substituted phenyl aminoethoxy)-3ꢀ/5ꢀ-
substituted benzylidenyl]-2,4-thiazolidinediones
(6a–f): General Procedure
5-[4ꢀ-(2ꢀꢀ-Sulphonamido-(4ꢀꢀꢀ-methyl)-phenyl ami-
noethoxy)benzylidenyl]-2,4-thiazolidinedione
(6d).
IR (KBr, cm−1): 3472 (2NH and NH2), 3125 (CH
aromatic), 2968 and 2942 (CH aliphatic asymmetric
and symmetric stretching vibrations, respectively),
1690 and 1564 (2CO stretching vibrations), 1431
(CN stretching), 1312 and 1154 (SO2 asymmetric
A mixture of 2 (0.005 mol), 4-amino-substituted
benzene sulphonamide (0.005 mol), powdered KOH
(0.006 mol), and a catalytic amount of a PTC was
dissolved in DMF (2 mL) and the reaction mixture
was exposed to 450-W MW radiation for 4–5 min.
It was then cooled and poured on to ice-cold water
and the reaction mixture was then neutralized to pH
7. Thus, the crude product obtained was crystallized
with aqueous DMF.
1
and symmetric), and 1259 (COC); H NMR (CDCl3
+ DMSO-d6, δ ppm): 2.91(s, 3H), 3.14 (t, 2H), 4.31
(t, 2H), 5.29 (br s, 1H, NH), 6.73–7.16 (m, 7H, Ar-H),
7.78 (s, 1H, vinylic-H), 10.18 (s, 2H, NH2), and 11.23
(br s, 1H, NH); Anal.: Calcd. for C19H19N3O5S2 (433):
N, 9.70; S, 14.79; Found: N, 9.68; S, 14.75.
5-[4ꢀ-(4ꢀꢀ-Sulphonamidophenyl
aminoethoxy)-
benzylidenyl]-2,4-thiazolidinedione (6a). IR (KBr,
cm−1): 3456 (2NH and NH2), 3104 (CH aromatic),
2950 and 2929 (CH aliphatic asymmetric and
symmetric stretching vibrations, respectively), 1676
and 1554 (2CO stretching vibrations), 1420 (CN
stretching), 1306 and 1143 (SO2 asymmetric and
5-[4ꢀ-(2ꢀꢀ-Sulphonamido-(4ꢀꢀꢀ-methyl)-phenyl ami-
noethoxy)-3ꢀ-methoxybenzylidenyl]-2,4-thiazolidine-
dione (6e). IR (KBr, cm−1): 3475 (2NH and NH2),
3121 (CH aromatic), 2970 and 2947 (CH aliphatic
asymmetric and symmetric stretching vibrations,
respectively), 1686 and 1558 (2CO stretching vibra-
tions), 1432 (CN stretching), 1320 and 1155 (SO2
symmetric), and 1253 (COC); 1H NMR (CDCl3
+
Heteroatom Chemistry DOI 10.1002/hc