Induced production of a new polyketide in sp. HS-11 by chemical epigenetic manipulation.

Chemical investigation into the culture broth of the plant endophyte sp. HS-11 in the modified Martin's medium supplemented with subemylanilide hydroxamic acid (SAHA), a well-known histone deacetylase (HDACs) inhibitor, led to the isolation and identification of two induced products 4-epipenicillone B () and ()-(+)-chrysogine (). 4-epipenicillone B () was obtained as a new compound whose structure was elucidated by comprehensive spectroscopic methods including 1 D/2D NMR, HRESMS, and quantum chemistry calculations including DFT GIAO C NMR and ECD calculation. Acquisition of 4-epipenicillone B () enriched the chemical diversities of fungal natural products possessing a tricyclo [5.3.1.0] undecane skeleton. The cytotoxic activity of was also evaluated.