[Studies on the quaternary alkaloids of Rauwolfia verticillata (Lour.) Baill var. hainanensis Tsiang].

Six alkaloids were isolated from the water soluble fraction of the roots of Rauvolfia verticillata (Lour.) Bail var. hainanensis Tsiang. Four of them were identified to be known alkaloids, as alkaloid Ⅰ (ajamaline), alkaloid Ⅱ (vellosimine), alkaloid Ⅲ (spegatrine) and alkaloid Ⅳ (verticillatine), Alkaloid Ⅴ and alkaloid Ⅵ are two new bis-indole alkaloids. The structure of alkaloid Ⅴ was assigned as 1 (dispegatrine) by spectral data (UV, IR, MS, ~1HNMR and ~(13)CNMR) and semisynthesized from spegatrine. The identification of Ⅵ is in progress. Alkaloid Ⅴ and Ⅵ are two α-adrenergic blocking agents.