title: Diversity Oriented Synthesis of Indoloazepinobenzimidazole and Benzimidazotriazolobenzodiazepine from N(1)-Alkyne-1,2-diamines.
abstract: A one-pot protocol for the diversity oriented synthesis of two N-polyheterocycles indoloazepinobenzimidazole and benzimidazotriazolobenzodiazepine from a common N(1)-alkyne-1,2-diamine building block is described. The approach involves sequential formation of benzimidazole through cyclocondensation and oxidation, which is followed by the formation of either an azepine ring (through alkyne activation and 6-endo-dig cyclization, 1,2-migration with ring expansion, and re-aromatization), or diazepine and triazole rings through 1,3-dipolar cycloaddition.
authors.affiliation: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow, 226031 (India).|Academy of Scientific and Innovative Research, New Delhi, 110001 (India).
authors.forename: Ravi
authors.initials: R
authors.lastname: Kumar
authors.affiliation: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow, 226031 (India).
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Arigela
authors.affiliation: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow, 226031 (India).
authors.forename: Srinivas
authors.initials: S
authors.lastname: Samala
authors.affiliation: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow, 226031 (India). bijoy_kundu@yahoo.com.|Academy of Scientific and Innovative Research, New Delhi, 110001 (India). bijoy_kundu@yahoo.com.
authors.forename: Bijoy
authors.initials: B
authors.lastname: Kundu
keywords: CC activation; cycloaddition; fused-ring systems; heterocycles; rearrangement