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References and Notes
29. 2-Methylthio-1H-benzimidazole (5). Ethanol–water (91%);
mp 201–203 ꢀC; 1H NMR (300 MHz, DMSO-d6) d 9.2 (bs, 1H,
NH), 7.4 (m, 2H, H-4, H-7), 7.1 (m, 2H, H-5, H-6), 2.7 (s, 3H,
CH3). MS: m/z 164 M+.
1. Byington, C. L.; Dunbrack, R. L.; Whitby, F. G.; Cohen,
F. E.; Agabian, N. Exp. Parasitol. 1997, 87, 194.
2. Fears, S. D.; O’Jare, J. Antimicrob. Agents. Chemother.
1998, 32, 144.
3. Cedillo-Rivera, R.; Munoz, O. J. Med. Microbiol. 1992, 37,
221.
4. Chavez, B.; Cedillo-Rivera, R.; Martinez-Palomo, A. J.
Protozool. 1992, 39, 510.
5. Hall, A.; Nahar, Q. Trans. Roy. Soc. Trop. Med. Hyg.
1993, 87, 84.
6. Romero-Cabello, R.; Robert, L.; Munoz-Garcia, R.;
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donado, M. Bol. Med. Hosp. Infant. Mex. 1996, 53, 173.
8. Chavez, B.; Espinosa, M.; Cedillo-Rivera, R.; Martınez, A.
Arch. Med. Res. 1992, 23, 63.
30. H-Benzimidazole (6). Water (80%); mp 172–173 ꢀC.
31. 5(6)-Chloro-2-methyl-ꢀ1H-benzimidazole (7). Acetone–
water (80%); mp 209–211 C; 1H NMR (300 MHz, DMSO-d6)
d 12.3 (bs, 1H, NH), 7.5 (d, J=1.8 Hz, 1H, H-4), 7.4 (d,
J=8.7 Hz, 1H, H-7), 7.1 (dd, J=8.7 Hz, J=1.8 Hz, 1H, H-6),
2.4 (s, 3H, CH3). MS: m/z 166 M+.
32. 2-Amino-5(6)-chloro-1H-benzimidazole
(8).
Water
(87%); mp 168–170 ꢀC; H NMR (300 MHz, DMSO-d6) d 8.8
(bs, 3H, NH), 7.7 (d, J=1.8 Hz, 1H, H-4), 7.2 (d, J=8.2 Hz,
1H, H-7), 7.2 (dd, J=8.2 Hz, J=1.8 Hz, 1H, H-6). MS: m/z
167 M+.
1
33. [5(6)-Chloro-1H-benzimidazol-2-yl] carbamic acid methyl
ester (9). DMF (54%); mp 296–297 ꢀC; H NMR (300 MHz,
1
DMSO-d6) d 11.7 (bs, 2H, NH), 7.4 (d, J=1.8 Hz, 1H, H-4),
7.4 (d, J=8.4 Hz, 1H, H-7), 7.1 (dd, J=8.4 Hz, J=1.8 Hz,
1H, H-6), 3.7 (s, 3H, CH3). MS: m/z 225 M+.
9. Werbovetz, K. A.; Brendle, J. J.; Sackett, D. L. Mol. Bio-
chem. Parasitol. 1999, 98, 53.
34. 5(6)-Chloro-1H-benzimidazole-2-(3H)-thione (10). Etha-
nol–water (53%); mp 327–329 ꢀC; 1H NMR (300 MHz,
DMSO-d6) d 12.7 (bs, 2H, NH), 7.1 (m, 3H, H-4, H-6, H-7).
MS: m/z 184 M+.
35. 5(6)-Chloro-2-methylthio-1H-benzimidazole (11). Toluene
(79%); mp 242–243 ꢀC; 1H NMR (300 MHz, DMSO-d6) d 12.2
(bs, 1H, NH), 7.4 (d, J=1.8 Hz, 1H, H-4), 7.3 (d, J=8.7 Hz,
1H, H-7), 7.0 (dd, J=8.7 Hz, J=1.8 Hz, 1H, H-6), 2.74 (s, 3H,
CH3). MS: m/z 198 M+.
10. Cook, C. G. Parasitol. Today 1990, 6, 133.
11. Friedman, P. A.; Platzer, E. G. Biochim. Biophys. Acta
1980, 630, 271.
12. Martin, R. J.; Robertson, A. P.; Bjorn, H. Parasitology
1997, 114 (Suppl.), S111.
13. Martin, R. J. Vet. J. 1997, 154, 11.
14. Lacey, E. Int. J. Parasitol. 1988, 18, 885.
15. Waller, P. J. Parasitol. Today 1990, 6, 127.
16. Upcroft, P.; Upcroft, J. Clin. Microbiol. Rev. 2001, 14, 150.
17. Navarrete-Vazquez, G.; Cedillo, R.; Hernandez-Campos,
A.; Yepez, L.; Hernandez-Luis, F.; Valdez, J.; Morales, R.;
Cortes, R.; Hernandez, M.; Castillo, R. Bioorg. Med. Chem.
Lett. 2001, 11, 187.
18. Phillips, M. A. J. Chem. Soc. 1928, 2393.
19. Leonard, N. J.; Curtin, D. Y.; Beck, K. M. J. Am. Chem.
Soc. 1947, 69, 2459.
20. Raeymakers, A. H.; VanGeider, J. L.; Roevens, L. F. C.;
Jansen, P. A. J. Arzeneim. Forsch. 1978, 28, 586.
21. Van Allan, J. A.; Deagon, B. D. Organic Syntheses Col-
lect; Wiley: New York, 1963. Vol. IV, p 569.
22. Iddon, B.; Kutschy, P.; Robinson, A. G.; Suschitzky, H.;
Kramer, W.; Neugebauer, F. J. Chem. Soc., Perkin Trans. 1
1992, 3129.
23. Skinner-Adams, T. S.; Davis, M. E.; Manning, L. S.;
Johnston, W. A. Trans. R. Soc. Trop. Med. Hyg. 1997, 91, 580.
24. Oxberry, M. E.; Reynoldson, J. A.; Thompson, R. C. A.
J. Vet. Pharmacol. Ther. 2000, 23, 113.
36. 5(6)-Chloro-1H-benzimidazole (12). Water (81%); mp
125–126 ꢀC; H NMR (300 MHz, DMSO-d6) d 12.7 (bs, 1H,
1
NH), 8.2 (s, 1H, H-2), 7.6 (d, J=1.8 Hz, 1H, H-4), 7.5 (d,
J=8.7 Hz, 1H, H-7), 7.1 (dd, J=8.7 Hz, J=1.8 Hz, 1H, H-6).
MS: m/z 152 M+.
37. 5,6-Dichloro-2-methyl-1H-benzimidazole (13). Methanol
(76%); mp 260–262 ꢀC; 1H NMR (300 MHz, DMSO-d6) 12
(bs, 1H, NH), 7.7 (s, 2H, H-4, H-7), 2.6 (s, 3H, CH3). MS: m/z
200 M+.
38. 2-Amino-5,6-dichloro-1H-benzimidazole (14). Ethanol–
water (86%); mp 260–262 ꢀC; 1H NMR (300 MHz, DMSO-d6)
d 10.9 (bs, 1H, NH), 7.3 (s, 2H, H-4, H-7), 6.5 (sb, 2H, NH2).
MS: m/z 201 M+.
39. (5,6-Dichloro-1H-benzimidazol-2-yl)
carbamic
acid
methyl ester (15). Ethanol (80%), mp 250–253 ꢀC; 1H NMR
(300 MHz, DMSO-d6) 11.8 (bs, 2H, NH), 7.6 (s, 2H, H-4, H-
7), 3.3 (s, 3H, CH3). MS: m/z 259 M+.
40. 5,6-Dichloro-1H-benzimidazole-2(3H)-thione (16). Acetic
acid (75%); mp 344–346 ꢀC; 1H NMR (300 MHz, DMSO-d6) d
12.7 (bs, 2H, NH), 7.3 (d, J=0.6, 2H, H-4, H-7). MS: m/z
218 M+.
41. 5,6-Dichloro-2-methylthio-1H-benzimidazole (17). Etha-
nol–water (89%); mp 234–235 ꢀC. 1H NMR (300 MHz,
DMSO-d6) d 12.8 (bs, 1H, NH), 7.6 (s, 2H, H-4, H-7), 2.6 (s,
3H, CH3). MS: m/z 232 M+.
25. 2-Methyl-1H-benzimidazole (1). Water (83%); mp 176–
178 ꢀC.
26. 2-Amino-1H-benzimidazole (2). Water (90%); mp 228–
229 ꢀC.
27. (1H-Benzimidazol-2-yl)carbamic acid methyl ester (3).
Ethanol (85%); mp 305–307 ꢀC; H NMR (300 MHz, DMSO-
1
d6) d 11.6 (bs, 2H, NH), 7.3 (m, 2H, H-4, H-7), 7.0 (m, 2H, H-
5, H-6), 3.7 (s, 3H, CH3). MS: m/z 191 M+.
28. H-Benzimidazole-2(3H)-thione (4). DMF (84%); mp 301–
303 ꢀC.
42. 5,6-Dichloro-1H-benzimidazole (18). Ethanol (76%), mp
208–209 ꢀC; 1H NMR (300 MHz, DMSO-d6) 11.2 (bs, 1H,
NH), 7.9 (s, 1H, H-2), 7.7 (s, 2H, H-4, H-7). MS: m/z 186 M+.