Anti-inflammatory sesquiterpene and triterpene acids from Hemsley.

Hemsley is a plant conventionally processed to provide popular food materials and herbal medicines in Asia. In this study, six triterpene acids, including five new ones (mesonaic acids D-H, -), and one proximadiol-type sesquiterpene () were isolated from the methanolic extract of the air-dried . Chemical structures of ‒ were established by spectroscopic methods, especially 2D NMR techniques (H-H COSY, HSQC, HMBC, and NOESY) and HRESIMS. Concerning their biological activities, compounds , , , and were examined manifesting high inhibition toward the pro-inflammatory NO production with EC values ranging from 12.88 to 21.21 µM, outrunning the positive control quercetin (24.12 µM). The mesoeudesmol B () identified from is the very first example, which exhibited high anti-inflammatory activity diminishing the level of the lipopolysaccharide-induced NO in RAW264.7 macrophage cells, thereby suppressing the secretion of pro-inflammatory cytokines TNF-α and IL-6 and the level of two critical downstream inflammatory mediators iNOS and COX-2.