Five New Guanacastane-Type Diterpenes from Cultures of the Fungus Psathyrella candolleana

摘要

Five new guanacastane-type diterpenes, named guanacastepenes P–T (1–5), were isolated from cultures of the fungus Psathyrella candolleana. Their structures were elucidated on the basis of extensive spectroscopic methods. All of the compounds were tested for their 11β-hydroxysteroid dehydrogenase (11β-HSD1) inhibitory activity. Compound 3 exhibited inhibitory activity against both human and mouse isozymes of 11β-HSD1 with IC50 values of 6.2 and 13.9?μM, respectively.