Department of Natural Medicines, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, 100191, People's Republic of China.
Nin Jiom Medicine Manufactory (H.K.) Limited, Hong Kong, 999077, People's Republic of China.
Phytochemistry. 2022 May;197:113129. doi: 10.1016/j.phytochem.2022.113129. Epub 2022 Feb 15.
Eight undescribed isosteroidal alkaloids cirrhosinones A-H (1-8), along with six known isosteroidal alkaloids (9-14), were isolated from the bulbs of Fritillaria cirrhosa D. Don. Their structures were determined by HRESIMS and 2D NMR analysis, and their absolute configurations were established by X-ray analysis. Compounds 1-8 possessed a typical cevanine-type alkaloid skeleton with a hydroxyl group rarely substituted at C-24 and compounds 4-8 possessed rare 7α or 7β-hydroxyl groups. This was the first report of both C-7 and C-24 hydroxyl groups substituted cevanine-type alkaloids. In addition, an approach for distinguishing D/E cis and trans conformations of cevanine-type alkaloids by H NMR data was developed. Moreover, the correlations between the relative configurations of 3-OH, 7-OH, 22-C, 24-OH, and 25-Me and the H NMR and C NMR data were also summarized. Compounds 1-9 exhibited moderate NO inhibitory activities in LPS-stimulated BV-2 cells at the concentration of 40 μM. The acetylcholinesterase inhibitory activities of compounds 1-7 and 9-10 were also evaluated and none of them showed acetylcholinesterase inhibitory activities at the concentrations of 20-80 μM.
从百合科贝母属植物甘肃贝母(Fritillaria cirrhosa D. Don)鳞茎中分离得到 8 个未见文献报道的异甾体生物碱类化合物(1-8)和 6 个已知同系物(9-14)。通过高分辨质谱和二维核磁解析确定了它们的结构，并通过 X 射线衍射解析确定了它们的绝对构型。化合物 1-8 具有典型的西贝母碱骨架，C-24 位很少有羟基取代，化合物 4-8 具有罕见的 7α 或 7β-羟基取代。这是首次报道 C-7 和 C-24 位羟基取代的西贝母碱。此外，还建立了通过 1H NMR 数据区分西贝母碱型生物碱 D/E 顺反式构型的方法。同时，还总结了 3-OH、7-OH、22-C、24-OH 和 25-Me 的相对构型与 1H NMR 和 13C NMR 数据之间的关系。化合物 1-9 在 40 μM 浓度下对 LPS 刺激的 BV-2 细胞表现出中等的 NO 抑制活性。还评价了化合物 1-7 和 9-10 的乙酰胆碱酯酶抑制活性，但它们在 20-80 μM 浓度下均无乙酰胆碱酯酶抑制活性。
