Phomopchalasins A (1) and B (2), two novel cytochalasans with unprecedented carbon skeletons, and phomopchalasin C (3), containing a rare hydroperoxyl motif, were obtained from the endophytic fungus Phomopsis sp. shj2, which was first isolated from the Isodon eriocalyx var. laxiflora. Their structures were elucidated by extensive spectroscopic analyses, electronic circular dichroism (ECD) calculation, and X-ray crystallographic analysis. Notably, 1 possessed an unprecedented 5/6/5/8-fused tetracyclic ring system, and 2 featured a novel 5/6/6/7/5-fused pentacyclic skeleton. The cytotoxic, anti-inflammatory, and antimigratory activities of 1-3 were evaluated in vitro.

Isopenicins A−C (1−3), three novel meroterpenoids possessing two types of unprecedented terpenoidpolyketide hybrid skeletons, were isolated from the cultures of Penicillium sp. sh18. Their structures were determined through synergetic use of extensive spectroscopic analysis, quantum-chemical calculation with ANN−PRA analysis, and X-ray crystallographic analysis. Additionally, the inhibitory activities of these compounds on the Wnt/β-catenin signaling pathway were evaluated, and 1 was identified as a potent inhibitor of the Wnt signaling pathway.