ORDER
REPRINTS
CONDENSED HETEROCYCLIC SYSTEMS
2847
3-( p-Methoxyphenyl)-6,7-dihydro-s-triazolo[3,4-b][1,3]thiazine (3b):
Yellow thick liquid, yield (69%); IR (film) n ¼ 3056 (¼CH), 2974, 2839
(C-H), 1655, 1602, 1472 (C¼C, C¼N), 1244, 1015 (C-N), 651 (C-S-C) cmÀ1
;
1H-NMR (DMSO-d6) d ¼ 7.28–7.63 (4H, m, ArH), 4.26–4.29 (2H, t,
CH2N), 3.83–3.85 (2H, t, CH2S), 4.01 (3H, s, CH3O), 2.59–2.62 (2H, m,
CH2) ppm; m/z : 247 (Mþ, 5), 218 (11), 135 (100). Calcd. for C12H13N3SO, C,
58.27; H, 5.29; H, 16.99. Found: C, 58.42; H, 5.28; N, 16.86.
3-(o-Methoxyphenyl)-5,6-(10,20-cyclohexyl)dihydrothiazolo[2,3-c]-
s-triazole (5a). Cream white solid, yield (68%); m.p. 195–196ꢀC, IR (KBr)
n ¼ 3070 (¼CH), 2984, 2890, 2828 (C-H), 1578, 1476 (C¼C, C¼N), 656
(C-S-C) cmÀ1
;
1H-NMR (DMSO-d6) d ¼ 7.01–7.66 (4H, m, ArH), 3.84
(3H, s, CH3O), 1.57–1.61 (8H, m, CH2) ppm; m/z: 287 (Mþ, 2), 207 (53),
117 (6), 91 (15), 44 (100); Calcd. for C15H17N3SO, C, 62.69; H, 5.96; N,
14.62. Found: C, 62.52; H, 5.98; N, 14.33.
3-Aryl-6-methyl[3,4-b][1,3,5]thiadiazine (4a–e): A mixture of 3-aryl-
5-mercapto-1,2,4-triazole (1) (0.006 mol), formaldehyde (0.014 mol), methyl-
amine (0.006 mol) was dissolved in ethanol and ethanol-HCl (10 mL). The
solution was stirred for 7 h at 55ꢀC and laid overnight, then the solvent was
removed giving a solid. The solid was washed with sodium bicarbonate (3%)
and recrystallized from ethanol.
3-( p-Nitrophenyl)-6-methyltriazolo[3,4-b][1,3,5]thiadiazine (4a): Yellow
solid, yield 82%; m.p.: 226ꢀC (decomp.). IR (KBr) n ¼ 3027, 3066 (¼CH),
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1665, 1602, 1428 (C¼C, C¼N), 636 (C-S-C) cmÀ1; H-NMR (DMSO-d6)
d ¼ 8.19–8.33 (4H, m, ArH), 4.94 (2H, s, SCH2N), 5.29 (2H, s, NCH2N),
2.56 (3H, s, CH3) ppm; m/z: Mþ29 (5.60), 278 (100), 235 (4.05), 176 (1.76);
Calcd. for C11H11N5SO2, C, 47.64; H, 4.00; N, 25.26. Found: C, 47.83;
H, 4.18; N, 25.03.
3-Phenyl-6-methyltriazolo[3,4-b][1,3,5]thiadiazine (4b): Light yellow
solid, yield (56%); m.p. 228–230ꢀC. IR (KBr) n ¼ 3047 (¼CH), 1526, 1480
(C¼C, C¼N), 685 (C-S-C) cmÀ1; 1H-NMR (DMSO-d6) d ¼ 2.66 (3H, s, CH3),
4.68 (2H, s, NCH2S), 5.12 (2H, s, NCH2N), 7.36–8.03 (5H, m, ArH) ppm;
m/z: 232 (Mþ, 100), 189 (29.65), 137 (84.85), 104 (50.77); Calcd.
for C11H12N4S, C, 56.87; H, 5.21; N, 24.12. Found: C, 56.73; H, 5.12;
N, 24.37.
3-(b-Pyridinyl)-6-methyltriazolo[3,4-b][1,3,5]thiadiazine (4c): Yellow
solid, yield (85%); m.p. 278–280ꢀC. IR (KBr) n ¼ 3049 (¼CH), 1604, 1580,
1470 (C¼C, C¼N), 630 (C-S-C) cmÀ1
;
1H-NMR (DMSO-d6) d ¼ 2.55
(3H, s, CH3), 4.92 (2H, s, NCH2S), 5.26 (2H, s, NCH2N), 7.48–9.11
(4H, m, PyH) ppm; Calcd. for C10H11N5S, C, 51.48; H, 4.75; N, 30.02.
Found: C, 51.79; H, 4.87; N, 30.39.
3-(o-Methoxyphenyl)-6-methyltriazolo[3,4-b][1,3,5]thiadiazine
(4d):
White solid, yield (48%); m.p.: 245–246ꢀC; H-NMR (DMSO-d6) d ¼ 2.73
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