Two new α-pyrone derivatives from an endolichenic fungus Tolypocladium sp.

Abstract

Two new α-pyrone derivatives, tolypocladones A (1) and B (2), together with five known compounds were isolated from an endolichenic fungus Tolypocladium sp. (4259a). The structures of all the compounds were determined by analysis of their MS and NMR data. Among them, compound 1 was an enantiomeric mixture and the configuration was established by single-crystal X-ray diffraction analysis using Cu–Kα radiation. Also, this is the first report of the presence of compound 3 (glycine, N-(2,3-dihydroxybenzoyl)-methyl ester) and compound 4 (2H-pyran-2-one, 4-methoxy-6-(1,3-pentadienyl)) as natural products.

Keywords:

• Endolichenic fungus
• Tolypocladium sp
• α-pyrone derivative

Acknowledgments

We thank Mr. Hong-Bo Zheng for the NMR measurements and Mrs. Yan-Hui Gao for the HRESIMS determination.