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

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.