Penipyrols C-G and methyl-penipyrol A, α-pyrone polyketides from the mangrove derived fungus Penicillium sp. HDN-11-131.

Six new α-pyrone polyketides, penipyrols C-G (1-5) and methyl-penipyrol A (6), together with one biogenetically related known compound, penipyrol A (7), were isolated from the extract of fungus Penicillium sp. HDN-11-131. Their structures including the absolute configurations were established by extensive spectroscopic analysis, Mosher's method, and ECD calculations as well as biogenic considerations. Compounds 1-4 possess a rare skeleton featuring γ-butyrolactone linked to α-pyrone ring through double bond. Compound 1 can induce pancreatic β-cell regeneration in zebrafish at 10 μM, which demonstrated promising anti-diabetes potential.