New Cadinane Sesquiterpenes from the Stems of Kadsura heteroclita

Abstract

As part of our continual efforts to exploit ‘Tujia Ethnomedicine’ for their pharmacophoric functionalities, we herein investigated Kadsura heteroclita collected from a deep Wulin mountain area in northern Hunan province. The current study resulted in the isolation of three new sesquiterpenes: 6α,9α,15-trihydroxycadinan-4-en-3-one (1), (+)-3,11,12-trihydroxycalamenene (2), (–)-3,10,11,12-tetrahydroxy-calamenene (3), along with four known sesquiterpenes (4–7), and a cytochalasin H (8). Their chemical structures were elucidated by 1D-, and 2D-NMR spectroscopy, and HRESI-MS, CD spectrometry. The antioxidant, and cytotoxic activities of the compounds were evaluated. Compound 8 exhibited a strong antioxidant effect with an IC50 value of 3.67 µM on isolated human polymorphonuclear cells or neutrophils.