Synthesis, antimicrobial and cytostatic activities of some derivatives of indolo[2,3-b]-1,5-benzothiazepine, a novel heterocyclic ring system

Abstract Some derivatives of indolo[2,3- b ]-1,5-benzothiazepine, a novel heterocyclic ring system, and of its 5,6-dihydroderivative have been obtained by Fischer indolization of corresponding phenylhydrazones. All the tetracyclic compounds were studied for their antimicrobial and cytostatic activities and several of them showed good activity against Gram-positive bacteria and Cryptococci .