Two novel indole alkaloids having unusual skeletons were isolated from the aerial part of Yunnan Kopsia
arborea. Kopsiyunnanine A (1) is a new class of bisindole alkaloid composed of vallesiachotamine (modified
Corynanthe-type) and Aspidospermatan-type alkaloids. Kopsiyunnanine B (2) is a new Corynanthetype
oxindole alkaloid rearranged by D ring rotation