228 Bogdanowicz et al.
1
81%); mp: 184–185◦C; H NMR (CDCl3) δ (ppm)δ
3172 (ν N−H), 2913 (ν C H), 1704 (ν C O), 1568 (ν
C C), 1505,1410 (ν C C), 1361, 1096 (ν C S), 958
(γ C H), 634 (γ N H)−. Anal. Calcd for C8H10N4OS2
(242.32): C, 39.65; H, 4.16; N, 23.12; S, 26.46. Found:
C, 39.61; H, 4.17; N, 23.08; S, 26.52.
1.96–2.06 (m, 4H, pyrrolidine), 2.85–2.95 (m, 2H,
morpholine), 3.25–2.35 (m, 4H, pyrrolidine), 3.53–
3.63 (m, 2H, morpholine), 3.80 (s, 3H, NCH3), 3.83–
3.93 (m, 2H, morpholine), 4.70–4.80 (m, 2H, mor-
pholine), 6.45 (dd, J1 = 5.9 Hz, J2 = 2.5 Hz, 1H, H-5),
7.20 (d, J = 2.5 Hz, 1H, H-3), 8.31 (d, J = 5.9 Hz, 1H,
H-6); IR (KBr, cm−1): 2845 (ν C H), 1605 (ν C C),
1542, 1330 (ν N N), 1109 (ν C S), 1002, 849, 709 (γ
C H), 535. Anal. Calcd for C16H22N6OS (346.45): C,
55.47; H, 6.40; N, 24.26; S, 9.26. Found: C, 55.36; H,
6.38; N, 24.33; S, 9.23.
General Procedure for the Synthesis of 7a and 7b
Compound 6a (0.309 g, 1 mmol) or 6b (0.242 g, 1
mmol) was dissolved in EtOH (5 mL), and TEA (0.5
mL, 3.5 mmol) was added. The mixture was refluxed
for 4 h. After cooling down, the precipitate was fil-
tered off and recrystallized from MeOH.
1-Methyl-4-(piperidin-1-yl)-3-[4-(pyrrolidin-1-yl)
3-Methyl-5-[4-(pyrrolidin-1-yl)pyridin-2-yl]-1,3,4-
oxadiazole-2(3H)-thione (7a). Product 7a was iso-
lated as a yellow solid (0.180 g, 69%); mp: 210–211◦C;
1H NMR (CDCl3) δ (ppm)δ 1.97–2.07 (m, 4H, pyrro-
lidine), 3.28–2.38 (m, 4H, pyrrolidine), 3.82 (s, 3H,
NCH3), 6.49 (dd, J1 = 6.1 Hz, J2 = 2.5 Hz, 1H, H-5),
7.01 (d, J = 2.5 Hz, 1H, H-3), 8.31 (d, J = 6.1 Hz, 1H,
H-3); IR (KBr, cm−1): 2846 (ν C H), 1601, 1483 (ν
C C), 1391, 1183 (ν C S), 1056 (ν C O), 1001, 832,
814, 738 (γ C H), 556−. Anal. Calcd for C12H14N4OS
(262.33): C, 54.94; H, 5.38; N, 21.36; S, 12.22. Found:
C, 55.08; H, 5.36; N, 21.41; S, 12.19.
pyridin-2-yl]-1H-1,2,4-triazole-5(4H)-thione
(8b).
Reaction with Methyl Piperidin-1-ylcarbamodithioate:
Product 8b was isolated as a white solid (0.299 g,
1
87%); mp: 105–107◦C; H NMR (CDCl3) δ (ppm)δ
1.55–1.87 (m, 6H, piperidine), 1.97–2.07 (m, 4H,
pyrrolidine), 2.93–3.03 (m, 2H, piperidine), 3.34–
3.44 (m, 4H, pyrrolidine), 3.82 (s, 3H, NCH3),
4.45–4.55 (m, 2H, piperidine), 6.46 (dd, J1 = 6.1 Hz,
J2 = 2.4 Hz, 1H, H-5), 7.45 (d, J = 2.4 Hz, 1H, H-3),
8.34 (d, J = 6.1 Hz, 1H, H-6); IR (KBr, cm−1): 2852
(ν C H), 1610 (ν C C), 1543 (ν C N), 1444 (ν C C),
1329, 1207, 1001, 799 (γ C H), 664−. Anal. Calcd
for C17H24N6S (344.48): C, 59.27; H, 7.02; N, 24.40;
S, 9.31. Found: C, 59.12; H, 6.99; N, 24.47; S, 9.33.
3-Methyl-5-(pyrimidin-2-yl)-1,3,4-oxadiazole-2(3H)-
thione (7b). Product 7b was obtained as a white
solid (0.129 g, 67%); mp: 254–255◦C; 1H NMR
(CDCl3) δ (ppm)δ 3.85 (s, 3H, NCH3), 7.49 (t, J =
5.1 Hz, 1H, H-5), 8.94 (d, J = 5.1 Hz, 2H, H-4,
H-6); IR (KBr, cm−1): 3068 (ν C H), 1565, 1477,
1426 (ν C C), 1394, 1353, 1300, 1155 (ν C S), 1051
(ν C O), 836, 757 (γ C H), 692−. Anal. Calcd for
C7H6N4OS (194.21): C, 43.29; H, 3.11; N, 28.85; S,
16.51. Found: C, 43.17; H, 3.12; N, 28.78; S, 16.48.
4-(Dimethylamino)-1-methyl-3-[4-(pyrrolidin-1-
yl) pyridin-2-yl]-1H-1,2,4-triazole-5(4H)-thione (8c).
Reaction with Methyl 2,2-Dimethylhydrazinecarbodi-
thioate: Product 8c was isolated as a white solid
1
(0.249 g, 82%); mp: 140–142◦C; H NMR (CDCl3) δ
(ppm)δ 2.06–2.16 (m, 4H, pyrrolidine), 3.43 (s, 6H,
2×NCH3), 3.49–3.59 (m, 4H, pyrrolidine), 3.81 (s,
3H, NCH3), 6.71 (dd, J1 = 5.1 Hz, J2 = 1.9 Hz, 1H,
H-5), 7.29 (s, 1H, H-3), 9.04 (s, 1H, H-6); IR (KBr,
cm−1): 2968 (ν C H), 1609 (ν C C), 1501, 1460 (ν
C C), 1390 (δ C H), 1332, 1205, 999, 805 (γ C H),
580. Anal. Calcd for C14H20N6S (304.41): C, 55.24; H,
6.62; N, 27.61; S, 10.53. Found: C, 55.08; H, 6.63; N,
27.69; S, 10.50.
General Procedure for the Synthesis of 8a–e
Compound 5a (0.220 g,
1
mmol) or 5b
(0.152 g, 1 mmol) was dissolved in dioxane
(3 mL), and 1 mmol of methyl morpholinocar-
bamodithioate (for 8a and 8d), methyl piperidin-
1-ylcarbamodithioate (for 8b and 8e), methyl
2,2-dihydrazinecarbodithioate (for 8c), and 10%
K2CO3 (3 mL) were added. The mixture was refluxed
for 6–20 h. Then the solvent was evaporated, 10 g of
ice was added, and the precipitate was filtered off
and crystallized from MeOH/H2O (1:1).
1-Methyl-4-morpholino-3-(pyrimidin-2-yl)-1H-1,2,
4-triazole-5(4H)-thione (8d). Reaction with Methyl
Morpholinocarbamodithioate: Product 8d was iso-
lated as a white solid (75 mg, 27%); mp: 142–145◦C;
1H NMR (CDCl3) δ (ppm)δ 2.92–3.02 (m, 2H,
morpholine), 3.37–3.47 (m, 2H, morpholine), 3.83
(s, 3H, NCH3), 3.76–3.86 (m, 2H, morpholine),
4.46–4.56 (m, 2H, morpholine), 7.42 (t, J = 4.9 Hz,
1H, H-5), 8.90 (d, J = 4.9 Hz, 2H, H-4, H-6); IR
(KBr, cm−1): 2853 (ν C H), 1563 (ν C C), 1397 (δ
C H), 1328, 1217, 1108 (ν C S), 1036, 847, 823 (γ
1-Methyl-4-morpholino-3-[4-(pyrrolidin-1-yl)
pyridin-2-yl]-1H-1,2,4-triazole-5(4H)-thione (8a).
Reaction with Methyl Morpholinocarbamodithioate:
Product 8a was isolated as a yellow solid (0.280 g,
Heteroatom Chemistry DOI 10.1002/hc