Marine Drugs, Vol. 19, Pages 575: Saliniquinone Derivatives, Saliniquinones Gâˆ`I and Heraclemycin E, from the Marine Animal-Derived Nocardiopsis aegyptia HDN19-252 (Marine Drugs)

Four new anthraquinone derivatives, namely saliniquinones Gâˆ`I (1âˆ`3) and heraclemycin E (4), were obtained from the Antarctic marine-derived actinomycete Nocardiopsis aegyptia HDN19-252, guided by the Global Natural Products Social (GNPS) molecular networking platform. Their structures, including absolute configurations, were elucidated by extensive NMR, MS, and ECD analyses. Compounds 1 and 2 showed promising inhibitory activity against six tested bacterial strains, including methicillin-resistant coagulase-negative staphylococci (MRCNS), with MIC values ranging from 3.1 to 12.5 μM.