A new protein tyrosine phosphatase 1B inhibitory α-pyrone-type polyketide from Okinawan plant-associated Aspergillus sp. TMPU1623.

A new polyenyl-α-pyrone polyketide, aspopyrone A (1), was isolated from a culture broth of Okinawan plant-associated Aspergillus sp. TMPU1623 by solvent extraction, ODS column chromatography, and preparative HPLC (ODS). The structure of 1 was assigned based on NMR experiments. Compound 1 exhibited protein tyrosine phosphatase (PTP) 1B and T-cell PTP (TCPTP) inhibitory activities with IC50 values of 6.7 and 6.0 µM, respectively.