Abstract
In order to examine the action as antimetabolite of cyanocobalamine, 5-fluorobenzimidazole and 2-mercapto-5-fluorobenzimidazole were synthesized from commercial ethyl p-aminobenzoate. 5-Fluorobenzimidazole, colorless needles, m. p. 133°, was obtained by the condensation-cyclization of 4-fluoro-o-phenylenediamine and formic acid, and 2-mercapto-5-fluorobenzimidazole, colorless needles, m. p. 283° (decomp.), by the condensation-cyclization of 4-fluoro-o-phenylenediamine, carbon disulfide, and ethanolic potassium hydroxide.
