New metabolites from the sea snail Mauritia arabica and their antimicrobial activity

One new sulfonated oxysterol sodium salt (1) and one new sterol (2), along with nine known compounds (311) were isolated from the sea snail Mauritia arabica. Their structures were elucidated by HRESIMS data, NMR spectroscopic analyses, and TDDFT-ECD calculations. Complete NMR data of compounds 3, 4 and 6, and ECD data of 6 are reported for the first time. In bioassays, compounds 13, 58, and 10 displayed antibacterial activity against Enterococcus faecalis with minimum inhibitory concentration (MIC) values ranging from 32 to 64 μg/mL. In addition, compounds 10 and 6 also showed antifungal activity against C. albicans with MIC values of 32 and 64 μg/mL, respectively.