Oxidative Routes to the Heterocyclic Cores of Benzothiazole Natural Products

Abstract

Methyl 6-(2-acetylaminoethyl)-4-hydroxy-benzothiazole-2-carboxylate, the benzothiazole core of the natural product violatinctamine, was prepared in a biomimetic oxidative route from <i>N</i>-acetyldopamine and cysteine methyl ester. In an alternative oxidative cyclization, ethyl 6-benzyloxy-5-methoxybenzo[<i>d</i>]thiazole-2-carboxylate, the heterocyclic core of erythrazole A, was also prepared.