Department of Chemistry, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
Phytochemistry. 2020 Aug;176:112391. doi: 10.1016/j.phytochem.2020.112391. Epub 2020 May 6.
Fourteen previously undescribed alkaloids comprising two N-1-hydroxymethylmacroline alkaloids, one talpinine-type oxindole acetal, a pair of equilibrating talpinine-type oxindole hemiacetals, eight oxidized derivatives of sarpagine- and akuammiline-type indole alkaloids, in addition to alstochalotine a diastereomer of gelsochalotine recently isolated from Gelsemium elegans, were isolated from the leaf and stem-bark extracts of Alstonia penangiana. The structures and relative configurations of these alkaloids were established using NMR, MS, and in one instance, confirmed by X-ray diffraction analysis. An NMR-based method is described as a useful chemotaxonomic tool for differentiating between A. penangiana and A. macrophylla. Several of the alkaloids isolated showed appreciable growth inhibitory effects when tested against a number of human cancer cell lines.
从 Alstonia penangiana 的叶和茎皮提取物中分离得到了 14 种以前未描述的生物碱，包括两种 N-1-羟甲基大环林生物碱、一种 talpinine 型吲哚内缩醛、一对平衡 talpinine 型吲哚半缩醛、8 种氧化衍生的 sarpagine 和 akuammiline 型吲哚生物碱，此外还有最近从 Gelsemium elegans 中分离得到的 alstochalotine，是 gelsochalotine 的非对映异构体。这些生物碱的结构和相对构型是通过 NMR、MS 确定的，在一个实例中，通过 X 射线衍射分析得到了证实。本文描述了一种基于 NMR 的方法，可作为区分 A. penangiana 和 A. macrophylla 的有用化学分类学工具。当对多种人类癌细胞系进行测试时，分离得到的几种生物碱表现出明显的生长抑制作用。
