Helioscopianoids A–Q, bioactive jatrophane diterpenoid esters from Euphorbia helioscopia

Abstract

The EtOH extracts of the whole plants of Euphorbia helioscopia afforded 17 new jatrophane diterpenoid esters, helioscopianoids A–Q (117), along with eight known compounds (18–25). Their structures were elucidated by extensive spectroscopic methods and Mo2(OAc)4-induced ECD analysis, and the structures of compounds 1, 2, and 7 were confirmed by X-ray crystallography. Compounds 1–17 were evaluated for inhibitory effects on P-glycoprotein (P-gp) in an adriamycin (ADM)-resistant human breast adenocarcinoma cell line (MCF-7/ADR) and neuroprotective effects against serum deprivation-induced and rotenone-induced PC12 cell damage. Compounds 8 and 16 increased the accumulation of ADM in MCF-7/ADR cells by approximately 3-fold at a concentration of 20 μmol/L. Compound 8 could attenuate rotenone-induced PC12 cell damage, and compounds 2, 8, and 12 showed neuroprotective activities against serum deprivation-induced PC12 cell damage. KEY WORDS: Euphorbia helioscopia, Jatrophanes, Helioscopianoids A–Q, P-glycoprotein (ABCB1) inhibitory activity, Neuroprotective effect