RSC Advances
Paper
2 3 3 3
exchangeable), 11.83 (s, 1H, OH, D O exchangeable); anal. calcd 3.43 (s, 3H, CH ), 3.82 (s, 3H, CH ), 3.84 (s, 3H, CH ), 6.81 (d,
for C H N O S (351.4): C, 64.94; H, 4.88; N, 11.96; found: C, 2H, Ar–H, J ¼ 8.4 Hz), 6.97 (d, 2H, Ar–H, J ¼ 8.4 Hz), 7.35–7.57
1
9
17 3 2
6
4.75; H, 4.80; N, 11.85%.
.1.2.c.4. 4-((E)-2,4-Dichlorobenzylidene)-2-(2-((E)-1-(p-tolyl)
ethylidene)hydrazinyl) thiazol-5(4H)-one (4d). White crystals;
(m, 3H, Ar–H), 8.25 (s, 1H, C]CH olenic), 9.96 (s, 1H, NH, D O
2
exchangeable), 11.87 (s, 1H, OH, D O exchangeable); anal. calcd
2
4
for C20
19 3 4
H N O S (397.4): C, 60.44; H, 4.82; N, 10.57; found: C,
60.24; H, 4.73; N, 10.46%.
ꢀ
ꢁ1
mp > 300 C; IR (KBr, cm ): 3115 (NH), 3066 (CH-aromatic),
1
2
(
2
945 (CH aliphatic), 1720 (C]O), 1644 (C]N); H NMR
DMSO-d ) d ppm: 3.30 (s, 3H, CH ), 3.98 (s, 3H, CH
H, Ar–H), 7.74 (d, 2H, Ar–H), 7.94 (d, 2H, Ar–H, J ¼ 8.4), 8.65 (4i). Off white crystals; mp > 300 C; IR (KBr, cm ): 3114,
4.1.2.c.9. 4-((E)-2,4-Dichlorobenzylidene)-2-(2-((E)-1-(3,4-
6
3
3
), 7.47 (d, dimethoxyphenyl)ethylid-ene)hydrazineyl) thiazol-5(4H)-one
ꢀ
ꢁ1
(
s, 1H, C]CH olenic), 8.66 (s, 1H of Ar–H), 12.09 (s, 1H, NH, (NH), 3066 (CH-aromatic), 2944 (CH aliphatic), 1721 (CO),
1
D
5
2
O exchangeable); anal. calcd for C19
6.44; H, 3.74; N, 10.39; found: C, 56.28; H, 3.65; N, 10.27%.
H
15Cl
2
N
3
OS (404.3): C, 1644 (C]N); H NMR (DMSO-d
3.82 (s, 3H, OCH ), 3.91 (s, 3H, OCH
H), 7.94 (m, 2H, Ar–H, J ¼ 8.4 Hz), 8.56 (s, 1H, C]CH olenic
1H, Ar–H), 12.06 (s, 1H, NH, D O exchangeable); anal.
6
) d ppm: 3.78 (s, 3H, CH
3
),
3
3
), 7.51–7.62 (m, 3H, Ar–
4.1.2.c.5. 4-((E)-3,4-Dimethoxybenzylidene)-2-(2-((E)-1-(p-
+
2
tolyl)ethylidene)hydrazinyl) thiazol-5(4H)-one (4e). Off white
crystals; mp 254–256 C; IR (KBr, cm ): 3114 (NH), 2949
calcd for C20H17C N O S (450.3): C, 53.34; H, 3.81; N, 9.33;
ꢀ
ꢁ1
l2
3
3
found: C, 53.15; H, 3.72; N, 9.22%.
1
(
CH aliphatic), 1704 (C]O), 1648 (C]N); H NMR (DMSO-
d ) d ppm: 3.32 (s, 3H, CH ), 3.67 (s, 3H, CH ), 3.83 (s, 3H,
4.1.2.c.10. 4-((E)-3,4-Dimethoxybenzylidene)-2-(2-((E)-1-(3,4-
6
3
3
OCH ), 3.88 (s, 3H, OCH ), 6.94–7.33 (m, 6H, Ar–H), 8.27 (s, dimethoxyphenyl)ethylid-ene)hydrazinyl)thiazol-5(4H)-one
(4j).
3
3
ꢀ
ꢁ1
1
H, C]CH olenic + s, 1H of Ar–H), 11.80 (s, 2H, NH, D O Yellow crystals; mp 232–236 C; IR (KBr, cm ): 3433, (NH), 2944
2
1
3
1
exchangeable), C NMR (DMSO-d
6
) d ppm: 178.2, 161.7, (CH aliphatic), 1707 (CO), 1648 (C]N); H NMR (DMSO-d
60.4, 158.3, 158.1, 157.1, 153.5, 142.6, 142.0, 139.4, 130.1, d ppm: 3.61 (s, 3H, CH ), 3.74 (s, 3H, OCH ), 3.79 (s, 3H, OCH
29.2 (2), 1284 (2), 112.3, 110.2, 56.6, 56.1, 33.4, 13.7; anal. 3.81 (s, 3H, OCH ), 3.86 (s, 3H, OCH
), 6.99 (d, 1H, Ar–H, J ¼ 8
S (395.5): C, 63.78; H, 5.35; N, 10.63; Hz), 7.05–7.15 (m, 3H, Ar–H), 7.55 (s, 1H, Ar–H), 8.29 (s, 1H, C]
found: C, 63.59; H, 5.27; N, 10.50%. CH olenic + 1H, Ar–H), 11.91 (s, 1H, NH, D O exchangeable);
anal. calcd for C H N O S (441.5): C, 59.85; H, 5.25; N, 9.52;
6
)
3
),
1
1
3
3
3
3
21 3 3
calcd for C21H N O
2
2
2
23 3 5
4.1.2.c.6. 4-((E)-2,4-Dihydroxybenzylidene)-2-(2-((E)-1-(p-tolyl)
found: C, 59.66; H, 5.17; N, 9.60%.
ethylidene)hydrazinyl) thiazol-5(4H)-one (4f). Red crystals; mp
over 300 C; IR (KBr, cm ): 3441 (OH), 3204 (NH), 3037 (CH-
aromatic), 2935 (CH aliphatic), 1697 (C]O), 1625 (C]N); H dimethoxyphenyl)ethylid-ene)hydrazinyl)thiazol-5(4H)-one
NMR (DMSO-d ) d ppm: 2.47 (s, 3H, CH ), 3.93 (s, 3H, CH ), Red crystals; mp > 300 C; IR (KBr, cm ): 3214, (NH), 3053 (CH-
ꢀ
ꢁ1
4.1.2.c.11. 4-((E)-2,4-Dihydroxybenzylidene)-2-(2-((E)-1-(3,4-
1
(4k).
ꢀ
ꢁ1
6
3
3
1
6.29–6.37 (m, 4H, Ar–H), 7.33 (d, 2H, Ar–H, J ¼ 8.4), 8.47 (s, 1H, aromatic), 2975 (CH aliphatic), 1697 (CO), 1633 (C]N); H NMR
C]CH olenic + s, 1H of Ar–H), 10.08 (s, 1H, NH, for thiazole (DMSO-d
6
) d ppm: 3.38 (s, 3H, CH
3 3
), 3.77 (s, 3H, OCH ), 3.86 (s,
tautomer,
D
2
O
exchangeable), 11.02 (s, 1H, 2OH,
D
2
O
O
3H, OCH
3
), 6.29–6.38 (m, 3H, Ar–H), 7.31 (d, 2H, Ar–H), 8.47 (s,
exchangeable), 11.94 (s, 1H, NH, for thiazole tautomer D
2
1H, C]CH olenic + 1H, Ar–H), 10.08 (s, 1H, NH, for thiazol
1
3
exchangeable); C NMR (DMSO-d
6
) d ppm: 174.0, 161.8 (2), tautomer,
60.6, 158.7(2), 133.0, 132.1, 110.8, 110.0, 109.0(2), 108.4(2), exchangeable), 11.95 (s, 1H, NH, for thiazole tautomer, D
02.8 (2), 102.0, 40.5, 19.7; anal. calcd for C19 S (367.4): exchangeable); anal. calcd for C20
D
2
O
exchangeable), 11.02 (s, 2H, OH,
D
2
2
O
O
1
1
H
17
N
3
O
3
H
19
N
3
O
5
S (413.4): C, 58.10; H,
C, 62.11; H, 4.66; N, 11.44; found: C, 61.89; H, 4.57; N, 11.31%. 4.63; N, 10.16; found: C, 57.26; H, 4.55; N, 10.06%.
.1.2.c.7. 2-(2-((E)-1-(3,4-Dimethoxyphenyl)ethylidene)hydra- 4.1.2.c.12. (E)-4-(Thiophen-2-ylmethylene)-2-(2-((E)-1-(p-tolyl)
zinyl)-4-((E)-4-methoxy benzylidene) thiazol-5(4H)-one (4g). White ethylidene)hydrazinyl) thiazol-5(4H)-one (5a). Orange crystals;
4
ꢀ
ꢁ1
ꢀ
ꢁ1
crystals; mp 240–242 C; IR (KBr, cm ): 3149 (NH), 3035 (CH- mp 202–204 C; IR (KBr, cm ): 3122 (NH), 3051 (CH-aromatic),
1
1
aromatic), 2964 (CH aliphatic), 1721 (C]O), 1621 (C]N); H 2950 (CH aliphatic), 1707 (C]O), 1634 (C]N); H NMR (DMSO-
NMR (DMSO-d ) d ppm: 3.82 (s, 3H, CH ), 3.84 (s, 3H, OCH ), d ) d ppm: 3.86 (s, 6H, 2CH ), 7.06 (d, 2H, Ar–H, J ¼ 8), 7.14 (m,
6
3
3
6
3
3.85 (s, 3H, OCH
3
), 3.86 (s, 3H, OCH
3
), 6.96 (d, 2H, Ar–H, J ¼ 8 1H, Ar–H), 7.26 (d, 2H, Ar–H, J ¼ 8), 7.56 (d, 1H, Ar–H), 7.73 (m,
Hz), 7.01 (s, 1H, Ar–H), 7.33 (d, 2H, Ar–H, J ¼ 8 Hz), 7.47 (d, 1H, 1H, Ar–H), 8.66 (s, 1H, C]CH olenic), 11.75 (s, 1H, NH, D
Ar–H, J ¼ 8 Hz), 7.68 (d, 1H, Ar–H, J ¼ 8 Hz), 8.31(s, 1H, C]CH exchangeable); anal. calcd for C17 OS (341.4): C, 59.80; H,
O exchangeable); C NMR 4.43; N, 12.31; found: C, 59.69; H, 4.35; N, 12.19%.
) d ppm: 160.1, 152.3, 151.0, 148.8, 130.8(2), 129.7,
23.5, 120.3(2), 114.7, 111.5(2), 111.2, 110.6, 109.6 (2), 55.9, 55.7,
5.6, 14.2; anal. calcd for C H N O S (411.5): C, 61.30; H,
2
O
H
15
N
3
2
1
3
olenic), 11.87 (s, 1H, NH, D
DMSO-d
2
(
6
4
.1.2.c.13. (E)-2-(2-((E)-1-(3,4-Dimethoxyphenyl)ethylidene)
1
5
5
hydrazinyl)-4-(thiophen-2-ylmethylene)thiazol-5(4H)-one (5b). Pale
2
1
21
3
4
ꢀ
ꢁ1
yellow crystals; mp 208–210 C; IR (KBr, cm ): 3411, (NH), 3053
.14; N, 10.21; found: C, 61.08; H, 5.04; N, 10.11%.
.1.2.c.8. 2-(2-((E)-1-(3,4-Dimethoxyphenyl)ethylidene)hydra-
zinyl)-4-((E)-4-hydroxy benzylidene)thiazol-5(4H)-one (4h). Yellow 3.85 (s, 3H, OCH ), 7.13–7.18 (m, 2H, Ar–H), 7.47–7.48 (d, 1H,
1
(
CH-aromatic), 2951 (CH aliphatic), 1709 (CO), 1633 (C]N); H
NMR (DMSO-d ) d ppm: 3.79 (s, 3H, CH ), 3.82 (s, 3H, OCH ),
4
6
3
3
3
ꢀ
ꢁ1
crystals; mp 290–292 C; IR (KBr, cm ): 3231 (NH), 2924 (CH Ar–H), 7.67 (d, 2H, Ar–H, J ¼ 5.2 Hz), 8.52 (s, 1H, C]CH olenic
1
6 2
aliphatic), 1687 (CO), 1639 (C]N); H NMR (DMSO-d ) d ppm: + 1H, Ar–H),11.90 (s, 1H, NH, D O exchangeable); anal. calcd for
2806 | RSC Adv., 2020, 10, 2791–2811
This journal is © The Royal Society of Chemistry 2020