1-Cyano-2,3-dimethylisothiourea → Cimetidine

Participants

Reaction Steps

A solution of 4-methyl-5-[(2-aminoethyl)thiomethyl]imidazole (17.0 g.) and N-cyano-N',S-dimethylisothiourea (11.2 g.) in acetonitrile (500 ml.) was heated under reflux for 24 hours. Following concentration, the residue was chromatographed on a column of silica gel with acetonitrile as eluant and the product obtained was finally recrystallised from acetonitrile-ether to yield N-cyano-N'-methyl-N"-[2-((4-methyl-5-imidazolyl)methylthio)ethyl]guanidine, m.p. 141°-2°. (Found: C, 47.2; H, 6.4; N, 33.4; S, 12.4. C10H16N6S requires: C, 47.6; H, 6.4; N, 33.3 S, 12.7).

Provenance & Evidence