ALMATARY ET AL.
13 of 16
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(
Z)-2-(2-(3-(Cyclopentyloxy)-4-methoxybenzylidene)hydrazinyl)-
of the reaction as judged by TLC the reaction mixture was allowed to
cool then poured into crushed ice. The formed solid was filtered off,
washed with water, dried and recrystallized from aqueous ethanol to
thiazol-4(5H)-one (15)
A mixture of compound 14 (0.293 g, 1 mmol), ethyl chloroacetate
1
(
0.122 g, 1 mmol) and sodium acetate (0.082 g, 1 mmol) was refluxed in
give the pure product. Buff solid. Mp: 140–141°C. H NMR (500 MHz,
acetic acid for 10 h. Upon completion of the reaction as judged by TLC,
the reactionmixturewasallowedtocoolthenitwaspouredintocrushed
ice. The formed solid was filtered off, washed with water, dried and
6
DMSO-d , δ, ppm) δ 11.87 (s, 1H), 7.88 (s, 1H), 7.2 (d, J = 2.0 Hz, 1H),
7.11 (dd, J = 8.2,2.0 Hz, 1H), 6.97 (d, J = 8.4 Hz, 1H), 6.61 (s, 1H),
4.85–4.74 (m, 1H), 4.07 (q, J = 7.0 Hz, 2H), 3.76 (s, 3H), 3.57 (s, 2H),
1
3
recrystallized from aqueous ethanol to give the pure product. Yield 48%.
2.05–1.40 (m, 8H), 1.18 (t, J = 7.1 Hz, 3H). C NMR (125 MHz, DMSO-
, δ, ppm) δ 170.65, 168.85, 151.58, 147.87, 142.49, 127.76, 120.92,
112.67, 111.82, 106.13, 80.24, 60.99, 56.25, 37.42, 32.03, 32.87,
24.42, 14.79. Elemental analysis for C20 S, calcd.: C, 59.53; H,
1
Brown solid. Mp: 220–221°C. H NMR (500 MHz, DMSO-d
6
, δ, ppm) δ
d
6
1
2
1.89 (s, 1H), 8.28 (s, 1H), 7.36 (d, J = 2.0 Hz, 1H), 7.25 (dd, J = 8.4,
.0 Hz, 1H), 7.02 (d, J = 8.4 Hz, 1H), 4.90–4.69 (m, 1H), 3.84 (s, 2H), 3.79
25 3 4
H N O
1
3
(
s, 3H), 1.99–1.50 (m, 8H). C NMR (125 MHz, DMSO-d
6
, δ, ppm) δ
76.00, 155.43, 152.20, 147.59, 127.66, 122.24, 112.54, 112.36,
0.09, 56.08, 33.79, 32.84, 24.23. Elemental analysis for C16 S,
6.25; N, 10.41. Found: C, 59.55; H, 6.27; N, 10.42.
1
8
19 3 3
H N O
|
4
.1.4 General procedure for the preparation of
calcd.: C, 57.64; H, 5.74; N, 12.60. Found: C, 57.66; H, 5.75; N, 12.61.
compounds 19a–c
A mixture of compound 14 (0.293 g, 1 mmol) and an appropriate
phenacyl bromide (1 mmol) was refluxed in ethanol till completion of
the reaction as judged by TLC. The reaction mixture was allowed to
cool then the solid was filtered off and recrystallized from ethanol.
(
Z)-2-(2-(2-(3-(Cyclopentyloxy)-4-methoxybenzylidene)-
hydrazinyl)-4-oxo-4,5-dihydrothiazol-5-yl)acetic acid (16)
A mixture of compound 14 (0.293 g, 1 mmol) and maleic anhydride
(
0.89 g, 1 mmol) were refluxed in toluene/DMF 25:1 for 12 h. After
completion of the reaction as judged by TLC, the reaction mixture was
allowed to cool then poured into crushed ice. The formed solid was
filtered off, washed with water, and recrystallized from aqueous ethanol
to give the pure product. Yield 40%. White solid. Mp: 236–237°C. IR
(
Z)-2-(2-(3-(Cyclopentyloxy)-4-methoxybenzylidene)hydrazinyl)-
-phenylthiazole (19a)
Yield 49%. Off-white solid. Mp: 170–171°C. H NMR (500 MHz,
DMSO-d , δ, ppm) δ 12.05 (s, 1H), 7.96 (s, 1H), 7.85 (d, J = 7.1 Hz, 2H),
.41 (t, J = 7.7 Hz, 2H), 7.35–7.22 (m, 2H), 7.27 (d, J = 1.9 Hz, 1H), 7.15
dd, J = 8.3, 1.8 Hz, 1H), 7.00 (d, J = 8.4 Hz, 1H), 4.83–4.70 (m, 1H), 3.77
5
1
6
−1
(
KBr, cm ) 3425 (NH), 3423 (OH), 2960 (aliph. CH), 1715 (CO), 1642
7
1
(
CO). H NMR (500 MHz, DMSO-d
6
, δ, ppm) δ 11.94 (s, 1H), 8.29 (s, 1H),
(
(
7
.34 (d, J = 2.0 Hz, 1H), 7.26 (dd, J = 8.3, 2.1 Hz, 1H), 7.01 (d, J = 8.4 Hz,
H), 4.89–4.68 (m, 1H), 4.33 (dd, J = 8.6, 3.9 Hz, 1H), 3.79 (s, 3H), 3.00
1
3
s, 3H), 1.93–1.51 (m, 8H). C NMR (126 MHz, DMSO-d
6
, δ, ppm) δ
69.12, 151.64, 147.90, 142.72, 129.32, 129.00, 128.52, 127.70,
26.26, 121.01, 112.68, 112.68, 111.80, 104.22, 80.26, 56.26, 33.04,
4.42. Elemental analysis for C22 S, calcd.: C, 67.15; H, 5.89;
1
1
1
2
(
dd, J = 17.6, 3.8 Hz, 1H), 2.89 (dd, J = 17.7, 8.6 Hz, 1H), 1.96–1.49 (m,
3
8
1
3
5
H). C NMR (125 MHz, δ, ppm) δ 175.98, 172.39, 156.68, 152.57,
23 3 2
H N O
47.75, 127.54, 122.59, 112.55, 112.55, 80.28, 56.26, 44.18, 37.26,
N, 10.68. Found: C, 67.17; H, 5.90; N, 10.70.
3.97, 32.99, 24.37. Elemental analysis for C18
21 3 5
H N O S, calcd.: C,
5.23; H, 5.41; N, 10.73. Found: C, 55.25; H, 5.42; N, 10.71.
(Z)-5-(4-Bromophenyl)-2-(2-(3-(cyclopentyloxy)-4-methoxy-
benzylidene)hydrazinyl)thiazole (19b)
(Z)-Methyl-2-(2-(2-(3-(cyclopentyloxy)-4-methoxybenzylidene)-
−1
Yield 60%. Buff solid. Mp: 210°C. IR (KBr, cm ) 3336 (NH), 2959 (aliph.
hydrazinyl)-4-oxo-4,5-dihydrothiazol-5-yl)acetate (17)
1
CH), 1625 (CN). H NMR (500 MHz, DMSO-d
1
, δ, ppm) δ 12.05 (s,
6
A mixture of compound 14 (0.293 g, 1 mmol) and DMAD (0.142 g,
H), 7.94 (s, 1H), 7.80 (d, J = 7.0 Hz, 2H), 7.59 (d, J = 10.9 Hz, 2H), 7.38 (s,
H), 7.26 (d, J = 2.0 Hz, 1H), 7.14 (dd, J = 8.3, 2.0 Hz, 1H), 6.99 (d,
1
mmol) was refluxed in ethanol. After 1 h, the formed solid was allowed
1
to cool and then filtered off and recrystallized from ethanol. Yield 42%.
J = 8.3 Hz, 1H), 4.83–4.70 (m, 1H), 3.77 (s, 3H), 1.93–1.51 (m, 8H).
13
−1
Yellow solid. Mp: 260–261°C. IR (KBr, cm ) 3424 (NH), 2954 (aliph.
6
C NMR (125 MHz, DMSO-d , δ, ppm) δ 169.41, 151.72, 150.73,
1
CH), 1727(CO), 1702 (CO), 1644 (CN). H NMR (500 MHz, DMSO-d
6
, δ,
1
48.06, 142.36, 137.79, 132.38, 128.37, 127.95, 121.31, 121.06,
12.84, 111.87, 105.18, 80.41, 56.42, 33.22, 24.60. Elemental analysis
ppm) δ 8.44 (s, 1H), 7.40 (d, J = 2.0 Hz, 1H), 7.37 (dd, J = 8.3, 2.0 Hz, 1H),
.07 (d, J = 8.4 Hz, 1H), 6.67 (s, 1H), 4.88–4.77 (m, 1H), 3.81 (s, 3H), 3.79
1
7
3 2
for C22H22BrN O S, calcd.: C, 55.94; H, 4.69;N,8.90. Found: C, 55.96;H,
1
3
(
s, 3H), 2.00–1.56 (m, 8H). C NMR (125 MHz, MHz, DMSO-d
δ 169.07, 151.38, 149.87, 147.73, 142.03, 132.05, 128.04, 127.61,
20.98, 120.73, 112.51, 111.54, 104.85, 80.08, 56.08, 32.88, 24.27.
Elemental analysis for C19 S, calcd.: C, 56.28; H, 5.72; N, 10.36.
Found: C, 56.29; H, 5.73; N, 10.37.
6
, δ, ppm)
4.68; N, 8.92.
1
(Z)-5-(4-Chlorophenyl)-2-(2-(3-(cyclopentyloxy)-4-methoxy-
H
23
N O
3 5
benzylidene)hydrazinyl)thiazole (19c)
1
Yield 48%. Buff solid. Mp: 190–191°C. H NMR (500 MHz, DMSO-d
6
,
δ, ppm) δ 12.05 (s, 1H), 7.94 (s, 1H), 7.80 (d, J = 7.0 Hz, 2H), 7.59
(d, J = 10.9 Hz, 2H), 7.38 (s, 1H), 7.26 (d, J = 2.0 Hz, 1H), 7.14 (dd,
J = 8.3, 2.0 Hz, 1H), 6.99 (d, J = 8.3 Hz, 1H), 4.83–4.70 (m, 1H), 3.77 (s,
(
Z)-Ethyl-2-(2-(3-(Cyclopentyloxy)-4-methoxybenzylidene)-
hydrazinyl)-4,5-dihydrothiazole-5-carboxylate (18)
1
3
A mixture of compound 14 (0.293 g, 1 mmol) and ethyl 4-chloroace-
toacetate (0.164 g, 1 mmol) was refluxed in ethanol. After completion
3H), 1.93–1.51 (m, 8H). C NMR (126 MHz, DMSO-d
6
, δ, ppm) δ
168.71, 151.04, 147.38, 141.73, 134.07, 131.69, 127.68, 127.26,