Structure elucidation and inhibitory effects on NO production of clerodane diterpenes from Ajuga decumbens

Abstract

Three new clerodane diterpenes (1-3), together with five known analogues (4-8), have been isolated from the whole plants of Ajuga decumbens. Their structures were established by detailed spectroscopic and spectrometric data analyses (IR, ESIMS, HR-ESIMS, 1D and 2D NMR). The inhibitory activities of these diterpenes on LPS-induced NO production were evaluated, and compounds 1-4 and 6-8 showed inhibitory effects.