Chaetolactam A, an Azaphilone Derivative from the Endophytic Fungus Chaetomium sp. g1.

Chaetolactam A (1), an unprecedented azaphilone derivative bearing a unique 9-oxa-7-azabicyclo[4.2.1]octan-8-onering system, together with two new compounds, 11-epi-chaetomugilide B (2) and chaetomugilide D (3) was isolated from an endophytic fungus, Chaetomium sp. g1. Notably, extensive NMR data analyses, NMR calculations with DP4 and DP4+ analyses, ECD calculations, and the RDC method were employed to establish the structure of 1. Furthermore, 2 exhibited potent apoptosis induction activity by mediating caspase-3 activation and PARP degradation at 3 µM in HL-60.

Isopenicins A-C: Two Types of Antitumor Meroterpenoids from the Plant Endophytic Fungus Penicillium sp. sh18.

Isopenicins A-C (1-3), three novel meroterpenoids possessing two types of unprecedented terpenoid-polyketide 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/ß-catenin signaling pathway were evaluated, and 1 was identified as a potent inhibitor of the Wnt signaling pathway.