Dihydroisocoumarins from the Mangrove-Derived Fungus Penicillium citrinum.

Three new dihydroisocoumarin penicimarins G-I (-), together with one known dihydroisocoumarin () and three known meroterpenoids (-), were obtained from a fungus isolated from the mangrove var. collected in the South China Sea. Their structures were elucidated by the detailed analysis of spectroscopic data. The absolute configuration of was determined by the X-ray diffraction analysis using Cu Kα radiation. The absolute configurations of and were determined by comparison of their circular dichroism (CD) spectra with the literature. All compounds were evaluated for their antibacterial activities and cytotoxic activities.