Gentiocrucines A–E, Five Unusual Lactonic Enamino Ketones from Swertia macrosperma and Swertia angustifolia

Abstract

Five unusual lactonic enamino ketones, gentiocrucines A–E (1–5), were isolated from Swertia macrosperma and S. angustifolia. Their structures were determined based on extensive spectroscopic analyses (IR, UV, MS, 1D- and 2D-NMR). By anti-HBV assay on the HepG 2.2.15 cell line in vitro, compound 1 inhibited both the secretion of hepatitis B virus surface antigen (HBsAg) and hepatitis B virus e antigen (HBeAg) with IC₅₀ values of 3.14 and 3.35 mM, and compound 5 only inhibited the secretion of HBsAg with an IC₅₀ value of 2.07 mM.

Key words

gentiocrucines A–E - Swertia macrosperma - Swertia angustifolia - Gentianaceae - lactonic enamino ketones - anti-HBV activity

^* These authors contributed equally to this work and are co-first authors.

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