New pestallic acids and diphenylketone derivatives from the marine alga-derived endophytic fungus Pestalotiopsis neglecta SCSIO41403.

Three new carboxylic acid derivatives, pestallic acids F and G (1 and 2), pestalotiopyrone N (3), and a new diphenylketone derivative named neopestalone (5) were obtained from the liquid cultures of marine alga-derived endophytic fungus Pestalotiopsis neglecta SCSIO41403, along with six known compounds (4, 6-10). The structures of those new compounds were elucidated mainly by analysis of their NMR and MS data. The isolated compounds were evaluated for their anti-Dengue virus and COX-2 inhibitory activities, and two diphenylketone derivatives (5 and 6) exhibited obvious COX-2 inhibitory activities, with the IC50 values being 5.8 and 3.4 μM, respectively.