Tetrahedron | 2019
Nitricquinomycins A-C, uncommon naphthopyrrolediones from the Streptomyces sp. ZS-A45
Abstract
Abstract Nitricquinomycins A-C (1∼3), three uncommon naphthopyrrolediones, together with one new compound (4), were isolated from the modified rice solid fermentation of the marine-derived Streptomyces sp. ZS-A45, an actinobacterium isolated from the marine sediments collected from Zhoushan island. Their structures were elucidated on the basis of MS, NMR spectroscopic and quantum chemical calculations of the electronic circular dichroism (ECD) spectra. Compounds 3 and 4 exhibited significant cytotoxicity against A2780\u202fcell lines with IC50 values of 4.77 and 2.92\u202fμM, respectively; on the other hand, compound 3 exhibited moderate antibacterial activities against Escherichia coli, Staphylococcus aureus and Candida albicans with MIC values of 20.0 40.0 and 40.0\u202fμM, respectively.