Title
Medermycin-Type Naphthoquinones from the Marine-Derived Streptomyces sp. XMA39
Author
Yong-Jun Jiang, Da-Shan Zhang, Hao-Jian Zhang, Jia-Qi Li, Wan-Jing Ding, Cheng-Dong Xu, Zhong-Jun Ma
Year
2018
Journal
Journal of Natural Products
Abstract
Four new medermycin-type naphthoquinones, strepoxepinmycins A–D (1–4), and one known compound, medermycin (5), were identified from Streptomyces sp. XMA39. Their structures were elucidated by analysis of HRESIMS, 1D and 2D NMR spectroscopic data, and ECD calculations. Among these compounds, strepoxepinmycin A (1) represents a rare 5,10-oxepindione ring system typically formed by a Baeyer–Villiger oxidation, and strepoxepinmycin B (2) is an isolation artifact derived from 1. Bioactivity evaluations of these compounds showed that compounds 3 and 4exhibited cytotoxicity against HCT-116 and PC-3 cancer cell lines and 4 exhibited moderate inhibition of ROCK 2 protein kinase. In addition, all of the new compounds showed antibacterial activity against Escherichia coli and methicillin-resistant Staphylococcus aureus and antifungal activity against Candida albicans.
Instrument
J-1500
Keywords
Circular dichroism, Absolute configuration, Natural products