Med Chem Res
(DMSO-d6) δ: 2.18 (s, 3H, CH3), 2.52 (s, 3H, CH3), 6.32 (s,
1H, pyrazole-C4-H), 6.89–7.88 (m, 11H, Ar–H and NH),
11.74 (s, 1H, OH, D2O exchangeable); 13C NMR (DMSO-
d6) δ: 15.8 (CH3), 20.3 (CH3), 97.2 (Ar–C), 101.7 (Ar–C),
114.5 (Ar–C), 115.3 (Ar–C), 123.8 (Ar–C), 123.9 (Ar–C),
130.1 (Ar–C), 130.9 (Ar–C), 138.7 (Ar–C), 143.2 (Ar–C),
150.8 (Ar–C), 160.4 (Ar–C), 162.1 (Ar–C), 165.2 (Ar–C),
173.8 (C=O); Anal. Calcd. for C21H19N5O2 (373.42): C,
67.55; H, 5.13; N, 18.76. Found: C, 67.71; H, 5.21; N,
18.68.
59.54; H, 4.44; N, 15.43. Found: C, 59.51; H, 4.23; N,
15.18.
General procedure for the synthesis of compounds 29–32
A mixture of the bipyrazole 19 or 21 (10 mmol) and the
appropriate aldehyde (10 mmol) in acetic acid (25 mL) was
heated under reflux for 8 h. The reaction mixture was con-
centrated and left to cool to room temperature. The sepa-
rated solid was filtered, washed with ethanol and
recrystallized from dimethylformamide.
5ʹ-Hydroxy-3ʹ,5-dimethyl-N,1ʹ-diphenyl-1ʹH,2H-[3,4ʹ-
bipyrazole]-2-carbothioamide (26) It was obtained as a pale
yellow solid; yield: 66%; m.p.: 245–247 °C; IR (KBr,
N-(4-Bromobenzylidene)-4-(5ʹ-hydroxy-3ʹ,5-dimethyl-
1ʹH,2H-[3,4ʹ-bipyrazol]-1ʹ-yl)benzenesulfonamide (29) It
was obtained as a yellow solid; yield: 76%; m.p.: 244–246 °C;
IR (KBr, cm−1) υ: 3362, 3290 (OH, NH), 1332, 1150
(SO2N); 1H NMR (DMSO-d6) δ: 2.16 (s, 3H, CH3), 2.54 (s,
3H, CH3), 6.69 (s, 1H, pyrazole-C4-H), 7.22–7.65 (m, 9H,
Ar–H and NH), 8.18 (s, 1H, CH=N), 15.53 (s, 1H, OH,
D2O exchangeable); 13C NMR (DMSO-d6) δ: 15.8 (CH3),
20.9 (CH3), 94.4 (Ar–C), 100.9 (Ar–C), 113.3 (Ar–C),
117.4 (Ar–C), 120.2 (Ar–C), 122.4 (Ar–C), 126.1 (Ar–C),
128.6 (Ar–C), 129.5 (Ar–C), 130.6 (Ar–C), 137.4 (Ar–C),
139.5 (Ar–C), 146.2 (Ar–C), 147.4 (Ar–C), 161.4 (CH=N);
Anal. Calcd. for C21H18BrN5O3S (500.38): C, 50.41; H,
3.63; N, 14.00. Found: C, 50.21; H, 3.52; N, 14.25.
N-(2,4-Difluorobenzylidene)-4-(5ʹ-hydroxy-3’,5-dime-
thyl-1ʹH,2H-[3,4ʹ-bipyrazol]-1ʹ-yl)benzenesulfonamide (30)
It was obtained as an orange solid; yield: 68%; m.p.:
262–264 °C; IR (KBr, cm−1) υ: 3348, 3312 (OH, NH),
1
cm−1) υ: 3375, 3332 (OH, NH), 1158 (C=S); H NMR
(DMSO-d6) δ: 2.11 (s, 3H, CH3), 2.42 (s, 3H, CH3), 6.38 (s,
1H, pyrazole-C4-H), 6.72–7.41 (m, 10H, Ar–H), 8.22 (s,
1H, NH, D2O exchangeable), 14.76 (s, 1H, OH, D2O
exchangeable); 13C NMR (DMSO-d6) δ: 15.2 (CH3), 20.5
(CH3), 105.9 (Ar–C), 110.5 (Ar–C), 118.9 (Ar–C), 120.5
(Ar–C), 124.1 (Ar–C), 126.0 (Ar–C), 128.8 (Ar–C), 129.0
(Ar–C), 129.1 (Ar–C), 136.3 (Ar–C), 138.2 (Ar–C), 139.7
(Ar–C), 144.4 (Ar–C), 154.2 (Ar–C), 163.4 (C=S); Anal.
Calcd. for C21H19N5OS (389.48): C, 64.76; H, 4.92; N,
17.98. Found: C, 64.64; H, 5.03; N, 17.87.
4-(5ʹ-Hydroxy-3ʹ,5-dimethyl-2-phenyl-1ʹH,2H-[3,4ʹ-
bipyrazol]-1ʹ-yl)-N-(phenylcarbamoyl)benzenesulfonamide
(27) It was obtained as a pale yellow solid; yield: 68%; m.
p.: 257–259 °C; IR (KBr, cm−1) υ: 3354–3267 (OH, NH),
1
1658 (C=O), 1368, 1182 (SO2N); H NMR (DMSO-d6) δ:
1
2.35 (s, 3H, CH3), 2.56 (s, 3H, CH3), 6.73 (s, 1H, pyrazole-
C4-H), 7.06–7.82 (m, 16H, Ar–H and 2NH), 12.14 (s, 1H,
OH, D2O exchangeable); 13C NMR (DMSO-d6) δ: 15.4
(CH3), 20.3 (CH3), 97.4 (Ar–C), 101.3 (Ar–C), 101.6
(Ar–C), 114.2 (Ar–C), 123.9 (Ar–C), 123.9 (Ar–C), 130.0
(Ar–C), 130.5 (Ar–C), 138.9 (Ar–C), 143.2 (Ar–C), 147.7
(Ar–C), 149.3 (Ar–C), 153.4 (Ar–C), 160.6 (Ar–C), 161.7
(Ar–C), 162.3 (Ar–C), 165.8 (Ar–C), 169.4 (Ar–C), 173.5
(C=O); Anal. Calcd. for C27H24N6O4S (528.59): C, 61.35;
H, 4.58; N, 15.90. Found: C, 61.62; H, 4.25; N, 15.82.
4-(5ʹ-Hydroxy-3ʹ,5-dimethyl-2-phenyl-1ʹH,2H-[3,4ʹ-
1342, 1155 (SO2N); H NMR (DMSO-d6) δ: 2.64 (s, 3H,
CH3), 2.95 (s, 3H, CH3), 6.11 (s, 1H, pyrazole-C4-H),
7.28–7.59 (m, 8H, Ar–H and NH), 8.23 (s, 1H, CH=N),
15.14 (s, 1H, OH, D2O exchangeable); 13C NMR (DMSO-
d6) δ: 15.8 (CH3), 20.3 (CH3), 94.5 (Ar–C), 100.9 (Ar–C),
113.7 (Ar–C), 117.9 (Ar–C), 120.8 (Ar–C), 122.9 (Ar–C),
126.5 (Ar–C), 128.8 (Ar–C), 129.6 (Ar–C), 130.8 (Ar–C),
137.2 (Ar–C), 139.5 (Ar–C), 146.6 (Ar–C), 147.6 (Ar–C),
158.9 (Ar–C), 160.3 (Ar–C), 161.5 (CH=N); Anal. Calcd.
for C21H17F2N5O3S (457.46): C, 55.14; H, 3.75; N, 15.31.
Found: C, 55.26; H, 3.77; N, 15.18.
bipyrazol]-1ʹ-yl)-N-(phenylcarbamothioyl)benzenesulfona-
mide (28) It was obtained as a pale yellow solid; yield:
69%; m.p.: 286–288 °C; IR (KBr, cm−1) υ: 3363–3288
(OH, NH), 1348, 1174 (SO2N), 1160 (C=S); 1H NMR
(DMSO-d6) δ: 2.52 (s, 3H, CH3), 2.86 (s, 3H, CH3), 6.93 (s,
1H, pyrazole-C4-H), 7.08–7.82 (m, 16H, Ar–H and 2NH),
11.92 (s, 1H, OH, D2O exchangeable); 13C NMR (DMSO-
d6) δ: 15.0 (CH3), 21.2 (CH3), 94.4 (Ar–C), 101.3 (Ar–C),
112.3 (Ar–C), 114.6 (Ar–C), 120.1 (Ar–C), 120.5 (Ar–C),
122.9 (Ar–C), 123.2 (Ar–C), 123.5 (Ar–C), 126.4 (Ar–C),
130.1 (Ar–C), 130.5 (Ar–C), 131.3 (Ar–C), 143.8 (Ar–C),
147.7 (Ar–C), 153.4 (Ar–C), 160.5 (Ar–C), 160.8 (Ar–C),
184.6 (C=S); Anal. Calcd. for C27H24N6O3S2 (544.66): C,
N-Benzylidene-4-(5ʹ-hydroxy-3ʹ,5-dimethyl-2-phenyl-
1ʹH,2H-[3,4ʹ-bipyrazol]-1ʹ-yl)benzenesulfonamide (31) It
was obtained as a pale yellow solid; yield: 70%; m.p.:
306–308 °C; IR (KBr, cm−1) υ: 3338 (OH), 1336, 1156
(SO2N); 1H NMR (DMSO-d6) δ: 2.36 (s, 3H, CH3), 2.48 (s,
3H, CH3), 6.46 (s, 1H, pyrazole-C4-H), 7.23–7.57 (m, 14H,
Ar–H), 8.19 (s, 1H, CH=N), 15.46 (s, 1H, OH, D2O
exchangeable); 13C NMR (DMSO-d6) δ: 15.8 (CH3), 20.7
(CH3), 94.8 (Ar–C), 100.9 (Ar–C), 113.2 (Ar–C), 117.6
(Ar–C), 120.6 (Ar–C), 122.6 (Ar–C), 126.3 (Ar–C), 127.5
(Ar–C), 128.7 (Ar–C), 129.3 (Ar–C), 129.3 (Ar–C), 130.5
(Ar–C), 137.8 (Ar–C), 139.9 (Ar–C), 146.7 (Ar–C), 147.3
(Ar–C), 158.7 (Ar–C), 160.3 (Ar–C), 161.2 (CH=N); Anal.