Penicindopene A, a new indole diterpene from the deep-sea fungus Penicillium sp. YPCMAC1

A new indole diterpene, named penicindopene A (1), together with seven known compounds (2 – 8), was isolated from the deep-sea fungus Penicillium sp. YPCMAC1. The structure of penicindopene A was elucidated by extensive spectroscopic analyses (1 D and 2 D NMR, and HRESIMS data), in addition to the ECD calculations for the assignments of its absolute configuration. Penicindopene A represented the first example of indole diterpenes possessing a 3-hydroxyl-2-indolone moiety, and it exhibited moderate cytotoxicities against A549 and HeLa cell lines with IC₅₀ values of 15.2 and 20.5 µM, respectively.