Mesoionic compounds with a bridged nitrogen atom. 18. Cyclization of (2-quinazolinylthio)acetic acids

It was established that mesoionic thiazoloquinazolinium oxides are formed in the action of acetic anhydride on (2-quinazolinylthio)acetic and -phenylacetic acids. The structures of the products were confirmed by their spectral characteristics and chemical transformtions.See [1] for Communication 17.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 817–822, June, 1989.