Enantiomeric pairs of meroterpenoids with 11/5/6 spiro-heterocyclic systems from Hypericum kouytchense

Abstract

Six undescribed enantiomeric pairs of acylphloroglucinol related meroterpenoids, (±)-hyperkouytins A–F (1a/1b–6a/6b), were isolated from Hypericum kouytchense. These enantiomers were acquired by chiral-phase HPLC, and their structures were established using spectroscopic and X-ray crystallographic data. These compounds incorporate a rare 11/5/6 heterocyclic system featuring a 1-oxaspiro[4.10]pentadecane moiety. Compounds 1b and 3a exerted antiproliferation activity against the MV-4-11 cell line.