Synthesis of 5<i>H</i>‐5‐oxobenzimidazo[2,1‐<i>b</i>]pyrido[3,2‐<i>e</i>][1,3]thiazine, A novel ring system

Abstract

Abstract Reaction between 2‐chloronicotinic acid chloride and 2‐mercaptobenzimidazole afforded 5 H ‐5‐oxobenzimidazo[2,1‐ b ]pyrido[3,2‐ e ][1,3]thiazine, a novel heterocyclic ring system. The assigned structure was confirmed by means of mass spectrometry.