Methane → Alosetron Hydrochloride

Participants

Reaction Steps

2,3,4,5-Tetrahydro-5-methyl-2-[(5-methyl-1H-imidazol-4-yl)methyl]-1H-pyrido[4,3-b]indol-1-one (1.00 g) was suspended in ethanol (40 ml) and concentrated hydrochloric acid (1.00 ml) was added. The mixture was warmed to 40° and charcoal (0.25 g) was added. The resulting suspension was stirred and warmed for 5 min. and then filtered. The filtrate was evaporated in vacuo to ca. 20 ml and was allowed to cool to 20°. Ether (40 ml) was added with stirring over 5 min., and the mixture was stored at 4° overnight. The resulting precipitate was filtered off, washed with ether (2×10 ml), dried in vacuo at room temperature for 2 h and then at 70° for 7 h to give the title compound (0.95 g), m.p. 288°-291°.

Provenance & Evidence