CHEMICAL STUDIES ON THE ALKALOIDS OF HU-MAN-TENG (GELSEMIUM ELEGANS BANTH.) Ⅰ. ISOLATION OF THE ALKALOIDS AND STRUCTURE OF HUMANTENMINE

From the roots of Hu-Man-Teng (Gelsemium elegans Banth.) seven alkaloids were isolated through basic alumina column and basic silica gel dry column chromatography as well as centrifugal thin layer chromatography. Three of them are known alkaloids, gelsevirine (Ⅲ), koumine (Ⅴ) and gelsemine (Ⅵ), the other fourare new alkaloids, named humantenmine, humantenine, humantenidine and humantenirine. Based on spectra data (UV, IR, ¹HNMR, ¹³CNMR and MS)and prepration of derivatives, the structure of humantenmine was elucidated as (Ⅰ).