A mycoparasite PG52 isolated from aeciospore piles of Aecidium pourthiaea was identified as Pestalotipsis sp. The chemical constituents of Pestalotipsis sp. PG52 were investigated. Four novel polyketides, named pestalpolyols E-H (1-4), were isolated from solid fermentations of Pestalotiopsis sp. PG52. Their structures were elucidated by interpretation of extensive spectroscopic methods, including 1D and 2D NMR, HR-MS experiments; and the absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis using the anomalous scattering of Cu Kα radiation. Compounds 2-4 showed cytotoxic activities against human tumor cell lines.
Keywords: Cytotoxic activity; Pestalotiopsis sp. PG52; Pestalpolyol; Polyketide.