Secondary Metabolites of the Lichen Parmotrema cristiferum

摘要

A new C41-spiroterpenoid, norreticulatin (1), has been isolated from the thalli of Parmotrema cristiferum together with four known compounds, anadensin (2), fusicoauritone (3), ergosterol (4), and betulin (5). The structure of the new compound 1 was determined through spectroscopic and MS analyses. Compound 1 exhibited potent inhibition, with an IC50 value of 8.8 μM, much lower than that of the acarbose-positive control (IC50 331 μM).