26
P.P. Bora et al. / Journal of Molecular Catalysis B: Enzymatic 92 (2013) 24–33
33, 55.2, 96.3, 120.2, 128, 128.8, 132, 132.1, 132.8, 135.4, 140, 145,
161. MS (ES+) m/z 321.0 (M+H)+, 343.0 (M+Na)+. Elemental analysis
for C14H10Cl2N4O: Calculated C 52.36, H 3.14, N 17.45; Observed C
2.4.11. 6-Amino-3-methyl-4-(pyridin-3-yl)-2,4-
dihydropyrano[2,3-c]pyrazole-5-carbonitrile,
1k
Dark brown colored solid; IR (KBr): 1049, 1414, 1493, 1606,
1646, 2203, 3177, 3350, 3396 cm−1 1H NMR (400 MHz, DMSO-d6):
;
ı 1.72 (s, 3H), 4.63 (s, 1H), 6.93 (s, 1H), 7.28 (dd, J = 3.2,12 Hz, 1H),
7.46 (d, J = 8 Hz, 1H), 8.38 (d, J = 2.4 Hz, 2H), 12.12 (s, 1H). 13C NMR
(100 MHz, DMSO-d6): ı 9.7, 33.6, 56.2, 96.7, 120.6, 123.8, 135.1,
135.7, 139.7, 148.2, 148.7, 154.7, 161.0. MS (ES+) m/z 254.0 (M+H)+.
Elemental analysis for C13H11N5O: Calculated C 61.65, H 4.38, N
27.65; Observed C 61.68, H 4.34, N 27.59.
2.4.6. 6-Amino-3-methyl-4-phenyl-2,4-dihydropyrano[2,3-
c]pyrazole-5-carbonitrile, 1f
[38]
White solid; IR (KBr): 1152, 1409, 1503, 1604, 2193, 3230,
3464 cm−1 1H NMR (400 MHz, DMSO-d6): ı 1.24 (s, 3H), 4.68
.
(s, 1H), 6.86 (s, 2H), 7.32–7.51 (m, 5H), 12.01 (s, 1H). 13C NMR
(100 MHz, DMSO-d6): ı 10, 35.6, 58.5, 115, 118, 121.2, 128.5, 131.2,
137.8, 156, 160.4. MS (ES+) m/z 253.0 (M+H)+, 275 (M+Na)+. Ele-
mental analysis for C14H12N4O: Calculated C 66.65, H 4.79, N 22.21;
2.4.12. 6-Amino-3-methyl-4-propyl-2,4-dihydropyrano[2,3-
c]pyrazole-5-carbonitrile, 1l
[37]
White solid; IR (KBr): 1064, 1402, 1501, 1603, 1953, 2174, 2928,
3165, 3378 cm−1 1H NMR (400 MHz, DMSO-d6): ı 0.77–0.85 (m,
.
3H) 1.19–1.23 (m, 2H), 1.65–1.74 (m, 2H), 1.90 (s, 3H) 3.19–3.24
(m, 1H), 6.66 (s, 2H), 11.89 (s, 1H). 13C NMR (100 MHz, DMSO-d6):
ı 9.6, 13.7, 19.8, 32.5, 36.5, 40, 96.6, 112.9, 139.5, 159, 171. MS (ES+)
m/z 219.0 (M+H)+. Elemental analysis for C11H14N4O: Calculated C
60.53, H 6.47, N 25.67; Observed: C 60.47, H 6.48, N 25.45.
2.4.7. 6-Amino-3-methyl-4-(4-methylphenyl)-2,4-
dihydropyrano[2,3-c]pyrazole-5-carbonitrile, 1g
[38]
White powder; IR (KBr): 1056, 1410, 1495, 1604, 1643, 2191,
3065, 3368 cm−1 1H NMR (400 MHz, DMSO-d6): ı 1.58 (s, 3H),
.
2.25 (s, 3H), 4.52 (s, 1H), 6.68 (s, 2H), 7.04–7.13 (m, 4H), 12.10 (s,
1H). 13C NMR (100 MHz, DMSO-d6): ı 9.9, 20.6, 36, 58, 97.4, 121,
127.3, 128.7, 135.4, 135.6, 141.1, 154.8, 160.5. MS (ES+) m/z 267.0
(M+H)+, 289 (M+Na)+. Elemental analysis for C15H14N4O: Calcu-
lated C 67.65, H 5.30, N 21.04; Observed C 67.48, H 5.53, N 20.96.
2.4.13. 6-Amino-3-methyl-4-pentyl-2,4-dihydropyrano[2,3-
c]pyrazole-5-carbonitrile, 1m
[40]
White solid; IR (KBr): 1164, 1226, 1401, 1495, 1613, 2197, 2946,
3141, 3403 cm−1 1H NMR (400 MHz, DMSO-d6): ı 0.81 (t, J = 6.4 Hz,
.
3H), 1.02–1.17 (m, 6H), 1.45–1.54 (m, 2H), 1.88 (s, 3H), 3.32 (t,
J = 4 Hz, 1H), 6.58 (s, 2H), 11.92 (s, 1H). 13C NMR (100 MHz, DMSO-
d6): ı 10.3, 14.2, 23.1, 24.4, 29.9, 32.2, 35.7, 56, 97.6, 120.9, 135.4,
156.2, 162. MS (ES+) m/z 247.0 (M+H)+, 269 (M+Na)+. Elemen-
tal analysis for C13H18N4O: Calculated C 63.39, H 7.37, N 22.75;
Observed: C 63.41, H 7.32, N 22.47.
2.4.8. 6-Amino-4-(3-hydroxyphenyl)-3-methyl-2,4-
dihydropyrano[2,3-c]pyrazole-5-carbonitrile,
1h
White solid; IR (KBr): 1062, 1275, 1407, 1480, 1600, 1653, 2183,
3177, 3370 cm−1 1H NMR (400 MHz, DMSO-d6): ı 1.80 (s, 3H), 4.47
.
(s, 1H), 6.52 (s, 1H), 6.6 (m, 2H), 6.85 (s, 2H), 7.08 (t, J = 8 Hz, 1H),
9.32 (s, 1H), 12.09 (s, 1H). 13C NMR (100 MHz, DMSO-d6): ı 14.9,
41.3, 62.4, 102.9, 119.0, 119.3, 123.4, 126.0, 134.5, 140.8, 151.2,
159.9, 162.6, 166.0. MS (ES+) m/z 269 (M+H)+. Elemental analysis
for C14H12N4O2: Calculated C 62.68, H 4.51, N 20.88; Observed C
2.4.14. 6-Amino-4-hexyl-3-methyl-2,4-dihydropyrano[2,3-
c]pyrazole-5-carbonitrile,
1n
White solid; IR (KBr): 731, 1069, 1401, 1487, 1606, 1646, 2190,
2925, 3131, 3264 cm−1 1H NMR (400 MHz, DMSO-d6): ı 0.76 (t,
.
J = 6.4 Hz, 3H), 0.90–1.14 (m, 8H), 1.48–1.55 (m, 2H), 2.08 (s, 3H),
3.49 (t, J = 4.4 Hz, 1H), 6.68 (s, 2H), 11.97 (s, 1H). 13C NMR (100 MHz,
DMSO-d6): ı 10.1, 13.9, 21.9, 23.7, 28.7, 29.5, 31.2, 34.8, 55.1,
96.7, 121.0, 134.8, 155.6, 161.8. MS (ES+) m/z 261.0 (M+H)+, 283.0
(M+Na)+. Elemental analysis for C14H20N4O: Calculated C 64.59, H
7.74, N 21.52; Observed C 64.42, H 7.59, N 21.61.
2.4.9. 6-Amino-4-(4-methoxyphenyl)-3-methyl-2,4-
dihydropyrano[2,3-c]pyrazole-5-carbonitrile, 1i
[38]
White solid; IR (KBr): 1250, 1403, 1502, 1604, 1652, 2196,
3380 cm−1 1H NMR (400 MHz, DMSO-d6): ı 1.80 (s, 3H), 3.56 (s,
.
2.4.15. 6-Amino-4-(2,2-dimethyl-1,3-dioxolan-4-yl)-3-methyl-
2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile,
1o
3H), 4.43 (s, 1H), 6.04 (s, 2H), 6.67–6.91 (m, 4H), 12.08 (s, 1H).
13C NMR (100 MHz, DMSO-d6): ı 9.8, 35.4, 57.5, 97.8, 114, 121,
128.5, 135.5, 136.5, 154.7, 158.0, 160.8. MS (ES+) m/z 283.0 (M+H)+.
Elemental analysis for C15H14N4O2: Calculated C 63.82, H 5.00, N
19.85; Observed C 63.71, H 4.93, N 20.01.
White solid; IR (KBr): 1023, 1169, 1268, 1401, 1600, 1712, 2190,
2932, 3376 cm−1 1H NMR (400 MHz, DMSO-d6): ı 1.16 (s, 3H), 1.25
.
(s, 3H), 2.13 (s, 3H), 3.50 (d, J = 6 Hz, 1H), 3.57 (t, J = 7.6 Hz, 1H), 3.83
(t, J = 7.2 Hz, 1H), 3.94 (q, J = 6.4, 12.4 Hz, 1H), 6.90 (s, 2H), 12.04
(s, 1H). 13C NMR (100 MHz, DMSO-d6): ı 10.4, 25, 25.9, 30.6, 33.9,
50.9, 65.9, 80.1, 95.3, 108.4, 121.4, 136.1, 155.5, 163.1. MS (ES+)
m/z 277 (M+H)+, 299 (M+Na)+. Elemental analysis for C13H16N4O3:
Calculated C 56.51, H 5.84, N 20.28; Observed C 56.60, H 5.89, N
20.15.
2.4.10. 6-Amino-4-(benzo[d][1,3]dioxol-5-yl)-3-methyl-2,4-
dihydropyrano[2,3-c]pyrazole-5-carbonitrile,
1j
Brown colored solid; IR (KBr): 1043, 1248, 1401, 1493, 1600,
1646, 2190, 3184, 3370 cm−1 1H NMR (400 MHz, DMSO-d6): ı 1.75
.
(s, 3H), 4.46 (s, 1H), 5.91 (s, 2H), 6.59 (m, 2H), 6.76 (s, 1H), 6.78 (s,
1H), 12.03 (s, 1H). 13C NMR (100 MHz, DMSO-d6): ı 9.7, 35.8, 57.3,
97.6, 100.9, 107.6, 107.9, 120.5, 120.7, 135.6, 138.5, 145.9, 147.3,
154.6, 160.7. MS (ES+) m/z 297.0 (M+H)+, 319.0 (M+Na)+. Elemen-
tal analysis for C15H12N4O3: Calculated C 60.81, H 4.08, N 18.91;
Observed C 60.76, H 4.04, N 18.95.
2.4.16. 6-Amino-3,4-dimethyl-4-phenyl-2,4-dihydropyrano[2,3-
c]pyrazole-5-carbonitrile, 2a
[38]
White solid; IR (KBr): 1407, 2186, 2893, 3240, 3426 cm−1 1H
.
NMR (400 MHz, DMSO-d6): ı 1.68 (s, 3H), 2.09 (s, 3H), 6.35 (s, 2H),
7.12–7.46 (m, 5H), 12.01 (s, 1H). 13C NMR (100 MHz, DMSO-d6): ı