Carcinogenic nitrogen compounds. Part LII. [1]Benzothiopyrano-[4,3-b]indoles, [1]benzopyrano[4,3-b]indoles, and related pseudo-azulenes

Abstract

[1]Benzothiopyrano[4,3-b]indole and several of its derivatives have been synthesised by various methods of dehydrogenation of the corresponding 6,11-dihydro-compounds. The structure and properties of these sulphur-containing heterocycles are investigated and compared with those of their oxygen analogues.