Arkivoc 2017, iii, 316-325
Myannik, K. A. et al.
С16H14N4O3S. Calcd for (M+H)+: 343.0859. Found: 343.0854.
N-(2,4-Dichlorophenyl)-5-(pyridin-3-yl)-1,3,4-thiadiazole-2-carboxamide (18d). Colorless crystals (85%); m.p.
o
1
205 С. H NMR (300 MHz, CDCl3) δ 9.26 (s, 1H, NH), 9.15 (s, 1H, Py), 8.83
(m, 1H,Py), 8.38 (d, J = 7.0 Hz, 1H,Py), 8.01 (s, 1H, Ar), 7.61–7.46 (m, 3H,
Ar+Py). 13C NMR (75 MHz, DMSO-d6) δ 170.0 (C, thiadiazole), 167.2 (1C,
C=O), 166.9 (C, thiadiazole), 156.0 (1C, Py), 152.2 (1C,Py), 148.1 (1C, Py),
136.2 (1C, Ar), 137.2 (1C, Py), 131.4 (1C, Ar), 130.1 (1C, Py), 125.9 (1C, Ar),
123.2 (1C, Ar), 122.1 (1C, Ar), 120.2 (1C, Ar). HRMS (ESI) С14H10Сl2N4OS. Calcd for (M+H)+: 350.9869. Found:
350.9865.
N-(4-Bromophenyl)-5-(pyridin-4-yl)-1,3,4-thiadiazole-2-carboxamide (18e). Colorless crystals (74%); m.p.
1
235 oС. H NMR (300 MHz, CDCl3) δ 9.15 (s, 1H, NH), 8.87 (d, J = 5.5 Hz, 2H,
Py), 7.92 (d, J = 5.6 Hz, 2H, Py), 7.65 (d, J = 8.8 Hz, 2H, Ar), 7.56 (d, J = 8.8 Hz,
2H,Ar). 13C NMR (75 MHz, DMSO-d6) δ 170.4 (C, thiadiazole), 167.2 (1C, C=O),
156.4 (C, thiadiazole), 151.4 (2C, Py), 137.4 (1C,Py), 136.3 (1C,Ar), 132.1 (2C,
Py), 123.2 (2C, Ar), 122.20 (2C, Ar), 117.25 (1C, Ar). HRMS (ESI) С14H9BrN4OS.
Calcd for (M+H)+: 360.9753. Found: 360.9743.
o
1
5-(Pyridin-4-yl)-N-(o-tolyl)-1,3,4-thiadiazole-2-carboxamide (18f). Colorless crystals (44%); m.p. 160 С. H
NMR (300 MHz, CDCl3) δ 9.12 (s, 1H, NH), 8.86 (d, J = 5.7 Hz, 2H,Py), 8.12 (d, J = 8.0
Hz, 1H,Ar), 7.91 (d, J = 5.9 Hz, 2H,Py), 7.33 (d, J = 7.7 Hz, 1H,Ar), 7.19 (t, J = 7.4 Hz,
1H,Ar), 2.45 (s, 3H,CH3). 13C NMR (75 MHz, DMSO-d6) δ 156.4 (1C, C=O), 151.4 (C,
thiadiazole), 151.0 (C, thiadiazole), 136.4 (2C, Py), 135.2 (2C, Py), 134.0 (1C, Ar),
130.9 (1C, Py), 127.2 (1C, Ar), 126.8 (1C, Ar), 126.6 (1C, Ar), 123.1 (1C, Ar), 122.2
(1C, Ar), 18.49 (1C, CH3). HRMS (ESI) С15H12N4OS. Calcd for (M+H)+: 297.0805. Found: 290.0801.
o
1
N-Phenyl-5-(pyridin-4-yl)-1,3,4-thiadiazole-2-carboxamide (18g). White crystals (80%); m.p. 210-212 С. H
NMR (300 MHz, DMSO-d6) δ 11.28 (s, 1H, NH), 8.83 (d, J = 5.6 Hz, 2H, Py), 8.05
(d, J = 5.7 Hz, 2H, Py), 7.87 (d, J = 7.9 Hz, 2H, Ar), 7.40 (t, J = 7.8 Hz, 2H, Ar), 7.19
(t, J = 7.3 Hz, 1H, Ar). 13C NMR (75 MHz, DMSO-d6) δ 170.3 (C, thiadiazole), 167.4
(1C, C=O), 156.3 (C, thiadiazole), 151.4 (2C, Py), 138.0 (1C, Py), 136.4 (1C, Ar),
129.2 (2C, Py), 125.3 (1C, Ar), 122.1 (2C, Ar), 121.3 (2C, Ar). HRMS (ESI)
С14H10N4OS. Calcd for (M+H)+: 283.0648. Found: 283.0646.
o
1
N-Phenyl-5-(pyridin-3-yl)-1,3,4-thiadiazole-2-carboxamide (18h). White crystals (60%); m.p. 190-192 С. H
NMR (300 MHz, DMSO-d6) δ 11.27 (s, 1H, NH), 9.28 (s, 1H, Py), 8.82 (d, J = 4.8 Hz,
N
1H, Py), 8.50 (dd, J = 4.4, 3.7 Hz, 1H, Py), 7.88 (d, J = 7.9 Hz, 2H, Ar), 7.66 (dd, J =
7.9, 4.9 Hz, 1H, Py), 7.41 (t, J = 7.8 Hz, 2H, Ar), 7.19 (t, J = 7.2 Hz, 1H, Ar). 13C NMR
O
S
(75 MHz, DMSO-d6) δ 169.5 (C, thiadiazole), 166.7 (C, thiadiazole), 166.6 (C=O),
N
HN
N
156.4 (1C,Py), 152.9 (1C, Py), 148.9 (1C, Py), 138.0 (1C, Py), 135.9 (1C, Ar), 129.2
(1C, Py), 125.2 (2C, Ar), 124.8 (1C, Ar), 121.3 (2C, Ar). HRMS (ESI) С14H10N4OS. Calcd for (M+H)+: 283.0648.
Found: 283.0646.
o
N-(Pyridin-2-yl)-5-(pyridin-3-yl)-1,3,4-thiadiazole-2-carboxamide (18i). White crystals (38%); m.p. 180-182 С.
1H NMR (300 MHz, CDCl3) δ 9.71 (s, 1H, NH), 9.02 (s, 1H, Py’), 8.82 (d, J = 4.1 Hz,
N
1H, Py’), 8.23 (d, J = 8.3 Hz, 1H, Py’), 7.92 (d, J = 7.8 Hz, 1H, Py), 7.82 (t, J = 7.4 Hz,
O
S
1H, Py), 7.52 (dd, J = 7.8, 4.9 Hz, 1H, Py’), 7.39 (dd, J = 7.7, 5.0 Hz, 1H, Py), 7.12-
7.03 (m, 1H, Py). 13C NMR (75 MHz, CDCl3) δ 171.9 (C, thiadiazole), 165.8 (C=O),
N
HN
N
N
153.4 (C, thiadiazole), 156.6 (1C, Py), 151.1 (1C, Py), 147.9 (1C, Py), 148.5 (1C, Py),
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