Résumé
Objective To study the alkaloids from the stems of Picrasma quassioidies. Methods The isolation and purification were carried out by column chromatography on CG161M, silica gel, ODS, and Sephadex LH-20. The structures were elucidated on the basis of physicochemical properties and spectroscopic analysis. Results A total of 16 alkaloids were isolated and identified from 85% ethanol aqueous extract of the stems of P. quassioidies. It included 12 β-carboline alkaloids including 1-(1-hydroxy)-ethyl-6-hydroxy-β-carboline (1), 6-hydroxy-β-carboline-1-carboxylic acid (2), β-carboline-1-carboxylic acid (3), β-carboline-1-propanoic acid (4), 3-hydroxy-β-carboline (5), 1-acetyl-β-carboline (6), 1-ethoxycarbonyl-β-carboline (7), 1-(9H-β-carbolin-1-yl)-ethanol (8), picrasidine X (9), 1-hydroxymethyl-β-carboline (10), 9H-pyrido [3,4-b] indole (11), 6-hydroxy-2-methyl-9H-β-carbolin-2-ium (12); and four cantin-6-one alkaloids, including 4,5-dimethoxycanthin-6-one (13), 3-methylcanthin-5,6-dione (14), 5-hydroxy-4-methoxylcanthin-6-one (15), and picrasidine O (16). Conclusion Compound 1 is a new β-carboline alkaloid named picrasidine Z, and compound 12 is a new natural product.