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Med Chem Res (2012) 21:1261–1270
s, COOH), 7.40–7.48 (4H, m, 40,70,200,600ArH), 7.28–7.31
(1H, dd, J = 1.5, 8.6 Hz, 50ArH), 7.12–7.14 (2H, d,
J = 7.8 Hz, 300,500ArH), 2.61 (3H, s, 3-CH3), 2.41 (3H, s,
5-CH3); MS: m/z 411 (M?). Elemental analysis: Calc. for
C19H14ClN5O2S: C, 55.41; H, 3.43; N, 17.00; found: C,
55.36; H, 3.38; N, 16.95%.
8.6 Hz, 50ArH), 6.95-6.97 (2H, d, J = 8.2 Hz, 300,500ArH),
3.91 (3H, s, OCH3), 2.59 (3H, s, 3-CH3), 2.46 (3H, s,
5-CH3); MS: m/z 446 (M?). Elemental analysis: Calc. for
C18H13BrClN5S: C, 48.39; H, 2.93; N, 15.68; found: C,
48.34; H, 2.90; N, 15.62%.
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(400-
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(200-
fluorophenylazo)pyrazole (4f)
carboxyphenylazo)pyrazole (4b)
Yield 55%; m.p. 180–182°C; IR (KBr, cm-1): 1634 (C=N),
1588 (–N=N–). H NMR (CDCl3, 300 MHz) d:7.83–7.88
(4H, m, 40,70,200,600ArH), 7.62–7.65 (1H, dd, J = 1.6, 8.2 Hz,
50ArH), 7.10–7.12 (2H, t, J = 8.2, 8.4 Hz, 300,500ArH), 2.62
(3H, s, 3-CH3), 2.24 (3H, s, 5-CH3); MS: m/z 385 (M?).
Elemental analysis: Calc. for C18H13ClFN5S: C, 56.03; H,
3.40; N, 18.15; found: C, 55.97; H, 3.33; N, 18.11%.
Yield 60%; m.p. 174–176°C; IR (KBr, cm-1): 1630 (C=N),
1584 (–N=N–). 1H NMR (CDCl3, 300 MHz) d: 12.14 (1H,
s, COOH), 7.88 (1H, d, J = 1.8, 70ArH), 7.78–7.80 (1H,
dd, J = 1.6, 8.2 Hz, 50ArH), 7.56–7.58 (1H, d, J = 7.8 Hz,
40ArH), 7.26–7.31 (4H, m, 300,400,500,600ArH), 2.78 (3H, s,
3-CH3), 2.48 (3H, s, 5-CH3); MS: m/z 411 (M?). Elemental
analysis: Calc. for C19H14ClN5O2S: C, 55.41; H, 3.43; N,
17.00; found: C, 55.34; H, 3.36; N, 16.97%.
1
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(400-
chlorophenylazo)pyrazole (4g)
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(200-
hydroxyphenylazo)pyrazole (4c)
Yield 58%; m.p. 218–220°C; IR (KBr, cm-1): 1632 (C=N),
1576 (–N=N–). H NMR (CDCl3, 300 MHz) d: 7.41–7.46
1
Yield 70%; m.p. 190–192°C; IR (KBr, cm-1): 3619 (O–H),
(4H, m, 40,70,200,600ArH), 7.32–7.35 (1H, dd, J = 1.6,
8.2 Hz, 50ArH), 6.96-6.98 (2H, d, J = 8.7 Hz, 300,500ArH),
2.48 (3H, s, 3-CH3), 2.20 (3H, s, 5-CH3); MS: m/z 401
(M?). Elemental analysis: Calc. for C18H13Cl2N5S: C,
53.74; H, 3.26; N, 17.41; found: C, 53.70; H, 3.21; N,
17.37%.
1
1640 (C=N), 1580 (–N=N–). H NMR (CDCl3, 300 MHz)
d: 11.65 (1H, s, OH), 7.41 (1H, d, J = 1.6, 70ArH),
7.36–7.38 (1H, dd, J = 1.8, 7.8 Hz, 50ArH), 7.13–7.15
(1H, d, J = 7.6 Hz, 40ArH), 6.96–7.02 (4H, m,
300,400,500,600ArH), 2.82 (3H, s, 3-CH3), 2.58 (3H, s, 5-CH3);
MS: m/z 383 (M?). Elemental analysis: Calc. for
C18H14ClN5OS: C, 56.32; H, 3.68; N, 18.24; found: C,
56.26; H, 3.64; N, 18.16%.
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(200-
chlorophenylazo)pyrazole (4h)
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(400-
Yield 60%; m.p. 240–242°C; IR (KBr, cm-1): 1624 (C=N),
1586 (–N=N–). H NMR (CDCl3, 300 MHz) d: 7.86 (1H,
1
methoxyphenylazo)pyrazole (4d)
d, J = 1.8, 70ArH), 7.74–7.77 (1H, dd, J = 1.6, 7.6 Hz,
50ArH), 7.56–7.58 (1H, d, J = 8 Hz, 40ArH), 7.19–7.24
(4H, m, 300,400,500,600ArH), 2.65 (3H, s, 3-CH3), 2.48 (3H, s,
5-CH3); MS: m/z 401 (M?). Elemental analysis: Calc. for
C18H13Cl2N5S: C, 53.74; H, 3.26; N, 17.41; found: C,
53.68; H, 3.24; N, 17.34%.
Yield 62%; m.p. 216–218°C; IR (KBr, cm-1): 1624 (C=N),
1572 (–N=N–). H NMR (CDCl3, 300 MHz) d: 7.82–7.87
1
(4H, m, 40,70,200,600ArH), 7.39–7.43 (1H, dd, J = 1.5,
9.3 Hz, 50ArH), 7.00–7.03 (2H, d, J = 9 Hz, 300,500ArH),
3.91 (3H, s, OCH3), 3.16 (3H, s, 3-CH3), 2.59 (3H, s,
5-CH3); 13C-NMR (CDCl3, 100 MHz) d: 161.57, 150.21,
147.70, 146.21, 141.75, 134.07, 130.44, 127.09, 123.89,
123.35, 120.99, 114.17, 55.59 (OCH3), 14.80 (CH3), 12.11
(CH3); MS: m/z 397 (M?). Elemental analysis: Calc. for
C19H16ClN5OS: C, 57.35; H, 4.05; N, 17.60; found: C,
57.27; H, 4.01; N, 17.54%.
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(400-
methylphenylazo)pyrazole (4i)
Yield 72%; m.p. 216–218°C; IR (KBr, cm-1): 1616 (C=N),
1
1564 (–N=N–). H NMR (CDCl3, 300 MHz) d: 7.67–7.72
1-(60-Chlorobenzothiazol-2-yl)-3,5-dimethyl-4-(400-
(4H, m, 40,70,200,600ArH), 7.47–7.49 (1H, dd, J = 1.8,
8.4 Hz, 50ArH), 6.98–7.0 (2H, d, J = 8.4 Hz, 300,500ArH),
2.60 (3H, s, 3-CH3), 2.42 (3H, s, 5-CH3) 2.12 (3H, s, Ar-
CH3); MS: m/z 381 (M?). Elemental analysis: Calc. for
C19H16ClN5S: C, 59.76; H, 4.22; N, 18.34; found: C,
59.72; H, 4.16; N, 18.30%.
bromoyphenylazo)pyrazole (4e)
Yield 60%; m.p. 238–240°C; IR (KBr, cm-1): 1610 (C=N),
1
1578 (–N=N–). H NMR (CDCl3, 300 MHz) d: 7.83–7.87
(4H, m, 40,70,200,600ArH), 7.43–7.45 (1H, dd, J = 1.8,
123