Alkaloids from twigs and leaves of Picrasma quassioides / 中草药

ABSTRACT

Objective To study alkaloids from the twigs and leaves of Picrasma quassioides. MethodsCompounds were isolated and purified by column chromatography over Sephadex LH-20 and silica gel column. Their chemical structures were elucidated on the basis of physicochemical properties and spectral data. Results Sixteen alkaloids were isolated, purified, and identified as 5-methoxycanthin-6-one (Ⅰ), 11-hydroxycanthin-6-one (Ⅱ), canthin-6-one (Ⅲ), 4, 5-dimethoxycanthin-6-one (Ⅳ), 4-methoxy-5-hydroxycanthin-6-one (Ⅴ), 3-methylcanthin-2, 6-dione (Ⅵ), 1-formyl-4-methoxy-?-carboline (Ⅶ), 1-methoxy-?-carboline (Ⅷ), 1-ethyl-4, 8-dimethoxy-?-carboline (Ⅸ), 1-methoxycarbonyl-4-hydroxyl-?-carboline (Ⅹ), 1-methyl-4-methoxy-?-carboline (Ⅺ), 1-ethoxycarbonyl-?-carboline (ⅩⅡ), 1-formyl-?-carboline (ⅩⅢ), 1-methoxycarbonyl-?-carboline (ⅩⅣ), 1-ethyl-4-methoxy-?-carboline (ⅩⅤ), and 1, 2, 3, 4-tetrahydro-1, 3, 4-trioxo-?-carboline (ⅩⅥ). Conclusion Compound Ⅺ is separated from the natural plant for the first time and compounds Ⅱ, Ⅷ, and ⅩⅤ are separated from plants of Picrasma Bl. for the first time.