Physalis angulata L. is a medicinal plant of the Solanaceae family, which is used to produce a variety of steroids. The present study reports on the cytotoxic withanolides of this plant. The species of Physalis angulata L. was identified by DNA barcoding techniques. Two new withanolides (1–2), together with six known analogues (3–8), were isolated from the whole plant of Physalis angulata L. The structures of these new compounds were determined on the basis of extensive spectroscopic data analyses and electronic circular dichroism (ECD) calculations. The withanolides exhibited strong cytotoxic activities against A549, Hela and p388 cell lines. Furthermore, compounds 1 and 2 induced typical apoptotic cell death in A549 cell line according to the evaluation of the apoptosis-inducing activity by flow cytometric analysis.
Five novel tyrosine-decahydrofluorene analogues, xenoacremones D–H (1–5), each bearing a fused 6/5/6 tricarbocyclic core and a 13-membered para-cyclophane ring system, were isolated from the endophytic fungus Xenoacremonium sinensis. Compound 1 was a novel polyketide synthase–nonribosomal peptide synthetase (PKS–NRPS) tyrosine-decahydrofluorene hybrid containing a 6/5/6/6/5 ring system. Their structures were elucidated from comprehensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. All compounds were evaluated for their inhibitory activities on LPS-induced NO production in macrophages and their cytotoxicities against the NB4 and U937 cell lines. Compounds 3 and 5 exhibited potent anti-inflammatory activities in vitro. Compounds 1 and 3–5 displayed significant antiproliferative activity against the tumor cell lines (IC50 < 20 µM).