One new ten-membered macrolide and one new pyridinone derivative from the mangrove endophytic fungus Alternaria porri # 25

One new ten-membered macrolide derivative, porriolide (1), and one new 2(1H)-pyridinone derivative (±)-porripyridone (2), together with seven known compounds alternariol 4-methyl ether (3), alternariol (4), 5'-methoxy-6-methylbiphenyl-3,4,3'-triol (5), altenusinoide A (6), harziano pyridone (7), penicilloxalone A (8), and cytosporin D (9) were obtained from mangrove endophytic fungus Alternaria porri #25. Their structures were elucidated using comprehensive spectroscopic methods, and the absolute configuration of the new compounds were further confirmed by ECD spectra and single-crystal X-ray diffraction analysis, respectively. Compounds 2 and 7 exhibited cytotoxic activities against prostate cancer VCap and PC-3 cells with IC50 values ranging from 22.94 ± 0.53 μmol/L to 38.13 ± 0.93 μmol/L, while compound 1 showed no cytotoxic activity.