A rearranged seco-steroid with new skeleton and five new abnormal progesteroids from Nodulisporium sp.

Abstract Abeo-nodulisporisteroid A ( 1 ), an abnormal steroid with a rearranged C3 chain at C-9 possibly derived from seco -ring A via Wagner-Meerwein rearrangement and oxidations, was obtained from Nodulisporium sp. together with five related new seco -progesteroids (nodulisporisteroids M-Q, 2 – 6 ), which were elucidated by the extensive spectroscopic analysis and X-ray crystallography. A plausible biosynthetic pathway of 1 – 6 was also proposed. Furthermore, these isolated compounds were also evaluated for cytotoxicities against five human tumour cell lines, antimicrobial activities, and inhibitions against PI3K gamma, Aβ 42 aggregation, and α-glucosidase.