Heterocyclic sulfonyl-carboximidamides
655
127.73, 129.49, 131.66, 131.89, 134.08, 139.76, 158.20
(2C), 158.89, 159.83 ppm.
6-Chloro-N0-(2-chlorophenylsulfonyl)pyrazine-2-
carboximidamide (11, C11H8Cl2N5O2S)
This compound was recrystallized from dioxane/methanol
N0-[(4-Chloropyridin-3-yl)sulfonyl]pyrimidine-2-
carboximidamide (8, C10H8ClN5O2S)
This compound was recrystallized from dioxane affording
(1:1) affording 1.1 g (85 %) 11. M.p.: 195–198 °C; IR
ꢀ
(KBr): m = 3,394, 3,288, 3,236 (m N–H), 1,642 (m C=N),
1,554 (m C=C), 1,522 (d N–H), 1,362, 1,297, 1,152, 11,07 (m
SO2), 892, 790, 757 (c C–H), 567 (c N–H) cm-1; 1H NMR
(500 MHz): d = 7.56–7.59 (m, 1H, Ph), 7.64–7.69 (m, 2H,
Ph), 8.18 (d, J = 7.8 Hz, 1H, Ph), 8.56 (br s, 1H, NH ? D2O
exchangeable), 9.07 (s, 1H, pyrazine), 9.13 (s, 1H, pyrazine),
9.34 (br s, 1H, NH ? D2O exchangeable) ppm; 13C NMR
(50 MHz): d = 127.77, 129.69, 132.04, 134.30, 139.27,
142.45, 144.56, 147.52, 148.42, 157.80, 158.70 ppm.
ꢀ
0.62 g (52 %) 8. M.p.: 162–163 °C; IR (KBr): m = 3,288
(m N–H), 1,623 (m C=N), 1,560, 1,397 (m C=C), 1,291,
1,219, 1,147 (m SO2), 840 (c C–H), 600 (c N–H) cm-1; 1H
NMR (200 MHz): d = 7.69–7.77 (m, 2H, 1H pyrimidine
and 1H 4-chloropyridine), 8.75 (d, J = 4.3 Hz, 1H,
4-chloropyridine), 8.85 (br s, 1H, NH ? D2O exchanga-
ble), 8.97 (d, J = 4.5 Hz, 2H, pyrimidine), 9.14 (s, 1H,
4-chloropyridine), 9.39 (br s, 1H, NH ? D2O exchangeable)
ppm; 13C NMR (50 MHz): d = 123.73, 126.67, 136.07,
141.94, 149.25, 154.26, 158.37 (2C), 160.53, 161.25 ppm.
6-Chloro-N0-[(4-chloropyridin-3-yl)sulfonyl]pyrazine-2-
carboximidamide (12, C10H7Cl2N5O2S)
This compound was recrystallized from methanol/water
N0-[(2-Chlorophenyl)sulfonyl]pyrazine-2-
carboximidamide (9, C11H9ClN4O2S)
(1:1) affording 0.64 g (48 %) 12. M.p.: 160–162 °C; IR
(KBr): m = 3,372 (m N–H), 3,092 (m C–H), 1,656 (m N=C),
ꢀ
This compound was recrystallized from ethanol affording
0.55 g (46 %) 9 for method A and 0.68 g (76 %) for
1,563, 1,547 (m C=C), 1,518 (d N–H), 1,368, 1,302, 1,150
(m SO2), 796 (c C–H), 601 (c N–H) cm-1 1H NMR
;
ꢀ
method B. M.p.: 173–174 °C; IR (KBr): m = 3,438, 3,356,
(500 MHz): d = 7.80 (d, J = 5.4 Hz, 1H, 4-chloropyri-
dine), 8.76 (br s, 1H, NH ? D2O exchangeable), 8.78 (d,
J = 5.4 Hz, 1H, 4-chloropyridine), 9.07 (s, 1H, pyrazine),
9.16 (s, 1H, 4-chloropyridine), 9.22 (s, 1H, pyrazine), 9.48
(br s, 1H, NH ? D2O exchangeable) ppm; 13C NMR
(50 MHz): d = 126.80, 135.48, 142.03, 142.61, 144.45,
147.49, 148.49, 149.42, 154.55, 158.13 ppm.
3,329, 3,254 (m N–H), 3,092 (m C–H), 1,615 (m C=N),
1,337, 1,278, 1,182, 1,153 (m SO2), 1,041 (d C–H), 592 (c
N–H) cm-1; H NMR (500 MHz): d = 7.57–7.59 (m, 1H,
1
Ph), 7.66–7.67 (m, 2H, Ph), 8.18 (d, J = 7.3 Hz, 1H, Ph),
8.53 (br s, 1H, NH ? D2O exchangeable), 8.20 (t,
J = 2.4 Hz, 1H, pyrazine), 8.81 (d, J = 2.4 Hz, 1H,
pyrazine), 9.20 (d, J = 1.4 Hz, 1H, pyrazine), 9.34 (br s,
1H, NH ? D2O exchangable) ppm; 13C NMR (50 MHz):
d = 127.76, 129.69, 131.58, 132.03, 134.22, 139.42,
144.03, 144.28 (2C), 148.58, 158.79 ppm; MS (-):
m/z = 613 (92 %, [2M?Na-3H]-), 297 (43 %, [M]-),
295 (100 %, [M-2H]-), 259 (79 %, [M-2H–Cl]-); MS
(?): m/z = 615 (29 %, [2M?Na-H]?), 319 (100 %,
[M?Na-H]?), 153 (71 %, [M-Cl–C6H4–NH2–O]?).
N0-(2-Chlorophenylsulfonyl)-6-methoxypyrazine-2-
carboximidamide (13, C12H11ClN4O3S)
This compound was recrystallized from methanol affording
ꢀ
0.75 g (76 %) 13. M.p.: 227–230 °C; IR (KBr): m = 3,401,
3,248 (m N–H), 1,643 (m C=N), 1,541 (m C=C), 1,381,
1,320, 1,281, 1,146, 1,106 (m SO2), 804 (c C–H), 584, 561
(c N–H) cm-1 1H NMR (200 MHz): d = 4.03 (s, 3H,
;
OCH3), 7.51–7.65 (m, 3H, Ph), 8.15–8.19 (m, 1H, Ph), 8.55
(s, 1H, pyrazine), 8.73 (s, 1H, pyrazine), 8.80 (br s, 1H,
NH ? D2O exchangeable), 9.00 (br s, 1H, NH ? D2O
exchangeable) ppm; 13C NMR (50 MHz): d = 54.59,
127.73, 129.61, 131.55, 132.03, 134.16, 135.74, 139.81
(2C), 140.87, 158.70, 159.08 ppm.
N0-[(4-Chloropyridin-3-yl)sulfonyl]pyrazine-2-
carboximidamide (10, C10H8ClN5O2S)
This compound was recrystallized from ethanol affording
0.79 g (66 %) 10 for method A and 0.38 g (42 %) for
ꢀ
method B. M.p.: 187–188 °C; IR (KBr): m = 3,380, 3,239
N0-[(4-Chloropyridin-3-yl)sulfonyl]-6-methoxypyrazine-2-
carboximidamide (14, C11H10ClN5O3S)
This compound was recrystallized from DMSO affording
(m N–H), 1,637 (m C=N), 1,560 (m C=C), 1,547 (d N–H),
1,285, 1,153, 1,120 (m SO2), 853, 793 (c C–H), 600
(c N–H) cm-1
;
1H NMR (200 MHz): d = 7.80
(d, J = 4.8 Hz, 1H, 4-chloropyridine), 8.57 (br s, 1H,
NH ? D2O exchangeable), 8.77–8.80 (m, 2H, 1H pyrazine
and 1H 4-chloropyridine), 8.92 (d, J = 3.2 Hz, 1H,
4-chloropyridine), 9.21–9.23 (m, 2H, pyrazine), 9.43 (br s,
1H, NH ? D2O exchangable) ppm; 13C NMR (50 MHz):
d = 126.79, 135.57, 141.98, 144.03, 144.43 (2C), 148.68,
149.44, 154.53, 159.11 ppm.
0.32 g (33 %) 14. M.p.: 265–270 °C (decomp.); IR (KBr):
m = 3,337, 3,302 (m N–H), 3,087 (m C–H), 1,642 (m C=N),
ꢀ
1,547, 1,450 (m C=C), 1,383, 1,280, 1,131 (m SO2), 1,008
(d C–H), 822, 777 (c C–H), 581 (c N–H) cm-1 1H
;
NMR (200 MHz): d = 4.04 (s, 3H, OCH3), 7.08 (d,
J = 5.1 Hz, 1H, 4-chloropyridine), 7.55 (s, 1H, pyrazine),
8.75–8.77 (m, 3H, 2H 4-chloropyridine and 1H NH ? D2O
123