Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41 Shinagawa-ku,Tokyo 142-8501, Japan.
Org Lett. 2010 Sep 17;12(18):4188-91. doi: 10.1021/ol101825f.
Two novel indole alkaloids, alsmaphorazines A and B, were isolated from the leaves of Alstonia pneumatophora (Apocynaceae), and their structures were determined on the basis of the 2D NMR and MS spectral analysis. These alkaloids possessed a new skeleton consisting of an 1,2-oxazinane and an isoxazolidine chromophore. The absolute configuration of alsmaphorazine B was determined by using CD spectral analysis. Alsmaphorazine A inhibited the NO production in the LPS-stimulated J774.1 cells dose-dependently without affecting the cell viability.
从杠柳（夹竹桃科）的叶子中分离得到两个新型吲哚生物碱，alsmaphorazines A 和 B，并基于二维 NMR 和 MS 光谱分析确定了它们的结构。这些生物碱具有由 1,2-噁嗪烷和异噁唑烷生色团组成的新型骨架。通过 CD 光谱分析确定了 alsmaphorazine B 的绝对构型。Alsmaphorazine A 可剂量依赖性地抑制 LPS 刺激的 J774.1 细胞中 NO 的产生，而不影响细胞活力。
