[A new alkaloid from Ervatamia hainanensis].

In order to study the alkaloids from branches and leaves of Ervatamia hainanensis, silica gel, ODS, Sephadex LH-20 and HPLC chromatography were used to obtain six alkaloids from the branches and leaves of E. hainanensis with use of. Based on the physicochemical properties and spectral data, their structures were identified as 10-hydroxydemethylhirsuteine(1), 3R-hydroxycoronaridine(2), 3-(2-oxopropyl)coronaridine(3), pandine(4), 16-epi-vobasine(5), and 16-epi-vobasinic acid(6). Among them, compound 1 was a new monoterpenoid indole alkaloid, and compounds 5 and 6 were obtained from this plant for the first time.

Hunzeylanines A-E, Five Bisindole Alkaloids Tethered with a Methylene Group from the Roots of Hunteria zeylanica.

Five novel bisindole alkaloids, hunzeylanines A-E (1-5), with an unprecedented skeleton were isolated from the roots of Hunteria zeylanica. Compounds 1-5 represent the first examples of akuammine-pleioarpamine-type bisindole alkaloids fused with a dihydropyran unit. Their structures including absolute configurations were established through comprehensive spectroscopic data analyses and computational calculation methods. The plausible biogenetic pathway of 1 was also proposed. Alkaloids 1 and 2 displayed moderate cytotoxicity toward three human cancer cell lines (MDA-MB-231, AV3, and Huh7).

Four new corynanthe-type alkaloids from the roots of Alstonia scholaris.

Four new corynanthe-type alkaloids, meloslines C-F (1-4), together with four known ones (5-8) were isolated from the roots of Alstonia scholaris. Their structures including absolute configurations were elucidated by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculation. Compounds 1 and 2 exhibited potent vasorelaxant activity on endothelium-intact renal arteries precontracted with KCl.