Vol. 28, No. 8 (2016)
Synthesis, Characterization and Biological Evaluation of Some New Oxino bis-Pyrazole Derivatives 1649
1
1
1
4
21.36, 126.20, 126.41, 127.17, 128.34, 128.85, 136.96,
40.90, 146.41, 157.66. EIMS, m/z (%): 418.2 (not observed),
06.2 (5), 384.3 (8), 287.1 (10), 262.1 (95), 185.1 (97), 174.1
1354, 1290, 1049, 1028, 798, 746, 694. H NMR (400 MHz,
DMSO-d
6
): δ = 2.35 (s, 6H, CH ), 5.06 (s, 1H, Ar-CH), 7.25
(t, 2H, PhH, J = 7.38 Hz), 7.35 (m, 1H, ArH), 7.44 (m, 4H,
ArH), 7.73 (dd, 5H, ArH, J = 8.48, 0.88 Hz), 8.43 (dd, 1H,
ArH, J = 4.78, 1.18 Hz), 8.51 (d, 1H, ArH, J = 2.27 Hz). C
NMR (100 MHz, DMSO-d ): δ = 12.11, 31.55, 104.50, 121.09,
123.84, 126.03, 129.21, 129.40, 125.78, 138.45, 146.70,
147.23, 149.00, 157.42.
3
(
44), 128.1 (2), 105.1 (38), 91.1 (68), 77.1 (79), 67.1 (40).
-(2-Furyl)-3,5-dimethyl-1,7-diphenyl-8-oxa-1,2,6,7-
tetraza-4,7-dihydro-1H-s-indacene (6): Yield: 1.0 g (49 %),
13
4
6
-1
m.p. 182-183 °C. IR (KBr, νmax, cm ): 1595, 1577, 1496, 1408,
1
1
373, 1282, 1008, 806, 785, 763, 752, 731, 673. H NMR (400
MHz, DMSO-d ): δ =2.30 (s, 6H, CH ), 4.98 (s, 1H, Ar-CH),
.12 (dd, 1H, Furan, J = 2.14, 1.07 Hz), 6.35 (dd, 1H, Furan,
6
3
3,5-Dimethyl-1,7-diphenyl-4-(4-pyridyl)-8-oxa-1,2,6,7-
tetraza-4,7-dihydro-1H-s-indacene (10):Yield 1.90 g (91 %),
6
-1
J = 1.30, 1.86 Hz), 7.25 (t, 2H, PhH, J = 7.31 Hz), 7.45 (t, 4H,
PhH, J = 8.20 Hz) 7.51 (s, 1H, Furan), 7.72 (d, 4H, PhH, J =
m.p. 160-162 °C. IR (KBr, νmax, cm ): 1699, 1593, 1575, 1494,
1
1489, 1410, 1276, 1066, 1024, 688, 678. H NMR (CDCl
3
): δ
13
7.66 Hz). C NMR (125 MHz, MeOD): δ =10.20, 28.56, 47.09,
48.11, 106.62, 121.73, 126.56, 127.03, 128.69, 129.10, 130.21,
141.17, 144.48, 154.12.
= 2.06 (s, 6H, CH ), 4.60 (s, 1H, Ar-CH), 6.99 (t, 2H, PhH, J
= 7.42 Hz), 7.07 (d, 2H, ArH, J = 5.76 Hz), 7.13 (t, 4H, PhH,
J = 7.74 Hz), 7.47 (d, 4H, PhH, J = 7.76 Hz), 8.12 (d, 2H,
3
13
3,5-Dimethyl-1,7-diphenyl-4-(2-thienyl)-8-oxa-1,2,6,7-
ArH, J = 6.09 Hz). C NMR (CDCl ): δ = 8.34, 11.80, 15.24,
3
tetraza-4,7-dihydro-1H-s-indacene (7): Yield: 1.82 g (85 %),
33.63, 45.60, 65.82, 121.41, 123.26, 126.25, 128.93, 137.19,
146.16, 148.57. HRMS, m/z (%): 460.2 (M K) (23), 482.2
(20), 501.2 (24), 523.2 (100).
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+
m.p. 194-195 °C. IR (KBr, νmax, cm ): 1595, 1575, 1492, 1408,
1
1
292, 931, 914, 783, 758, 669. H NMR (400 MHz, DMSO-d
δ=2.34 (s, 6H, CH ), 5.15 (s, 1H,Ar-CH), 6.77 (t, 1H, Thiophene,
J = 1.94 Hz), 6.92 (dd, 1H, Thiophene, J = 5.06, 3.56 Hz),
6
):
3
(E)-2-(3,5-Dimethyl-1,7-diphenyl-8-oxa-1,2,6,7-tetraza-
4,7-dihydro-1H-s-indacen-4-yl)-1-phenyl-1-propene (11):
-1
7.26 (t, 2H, PhH, J = 7.34 Hz), 7.31 (d, 1H, Thiophene, J =
Yield: 1.75 g (76 %), m.p. 178-180 °C. IR (KBr, νmax, cm ):
5
=
.04 Hz), 7.46 (t, 4H, PhH, J = 8.12 Hz), 7.74 (d, 4H, PhH, J
1737, 1597, 1577, 1502, 1375, 1348, 1332, 1255, 1232, 1186,
13
1
6
7.71 Hz). C NMR (125 MHz, DMSO-d ): δ =11.96, 29.93,
1022, 852, 750, 613. H NMR (400 MHz, CDCl
3
) δ =1.52 (s,
), 3.90 (s, 1H, Ar-CH), 6.16 (s, 1H,
Ph-CH), 6.89 (t, 6H, PhH, J = 7.41 Hz), 7.09 (t, 3H, PhH, J =
4
1
0.13, 121.06, 124.62, 126.11, 127.24, 129.41, 146.32, 147.90,
56.40, 157.09, 158.23.
3H, CH
3
), 1.87 (s, 6H, CH
3
13
3,5-Dimethyl-1,7-diphenyl-4-(2-pyridyl)-8-oxa-1,2,6,7-
5.96 Hz) 7.42 (d, 4H, PhH, J = 7.66 Hz). C NMR (125 MHz,
MeOD): δ =10.31, 16.50, 24.43, 37.32, 114.70, 121.61,
125.30, 125.68, 126.48, 127.60, 128.64, 136.10, 138.50,
155.76, 156.32, 156.85.
tetraza-4,7-dihydro-1H-s-indacene (8): Yield: 1.0 g (67 %),
m.p. 193-195 °C. IR (KBr, νmax, cm ): 1593, 1518, 1489, 1410,
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352, 1273, 1099, 1031, 1008, 896, 785, 690, 678. H NMR
(
400 MHz, DMSO-d ): δ = 2.29 (s, 6H, CH ), 5.12 (s, 1H, Ar-
6
3
RESULTS AND DISCUSSION
CH), 7.24 (m, 3H, ArH), 7.44 (m, 5H, ArH), 7.72 (d, 2H,ArH,
J = 7.82 Hz), 7.79 (dd, 3H, ArH, J = 6.58, 0.93 Hz), 8.51 (d,
Since various reactions of compound 2 with malononitrile
and arylaldehydes have been reported to give 6-amino-4-aryl-
5-cyano-3-methyl-1-phenyl pyrano[3,4,c]pyrazoles [19], it
was expected that a similar reaction with cyanoacetamide will
provide the expected product 3 (Scheme-I). However a close
examination of the analytical data from a reaction with
benzaldehyde showed absence of any absorption due to an
expected amino functional group and a carbonyl of an amide
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1
1
1
H, ArH, J = 4.06 Hz). C NMR (100 MHz, DMSO-d ): δ =
2.11, 37.05, 114.60, 120.81, 122.13, 122.44, 125.82, 129.34,
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37.68, 138.20, 147.10, 148.64, 157.32, 161.72. HRMS, m/z
+
(
%): 460.2 (M K) (100), 482.2 (47), 501.2 (32), 523.2 (31).
3,5-Dimethyl-1,7-diphenyl-4-(3-pyridyl)-8-oxa-1,2,6,7-
tetraza-4,7-dihydro-1H-s-indacene (9): Yield: 2.60 g (98 %),
-1
m.p. 248-249 °C. IR (KBr, νmax, cm ): 1593, 1577, 1496, 1421,
R
O
H C
3
NH2
N
N
N
O
NH2
O
Stirring
R
O
R
3
NC
2
NH2
Triethyl
amine
H
NH2
H
O
R
O
Triethyl amine
Stirring
CN
H C
CH3
3
1
N
N
N
R = phenyl, furyl, thiophenyl, 2-, 3- or 4-pyridyl, cinnamyl group
Scheme-I: Synthesis of bis-pyrazoles 4 with alkyl and aryl aldehydes
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