Bhimamycin D

Chemical investigation on a Streptomyces sp. strain MS180069 isolated from a sediment sample collected from the South China Sea, yielded the new benzo[f]isoindole-dione alkaloid, bhimamycin J (1). The structure was determined by extensive spectroscopic analysis, including HRMS, 1D, 2D NMR, and X-ray diffraction techniques. A molecular docking study revealed 1 as a new molecular motif that binds with human angiotensin converting enzyme2 (ACE2), recently described as the cell surface receptor responsible for uptake of 2019-CoV-2. Using enzyme assays we confirm that 1 inhibits human ACE2 79.7 % at 25 μg/mL.

From the ethyl acetate extract of a terrestrial Streptomycete isolate, five new quinone antibiotics, bhimamycin A (2a), B (2b), C (3c), D (5a), E (7) and the new tetralone bhimanone (8) were isolated together with the known microbial products chrysophanol (1a), aloesaponarin II (1b), 3,8-dihydroxy-1-methylanthraquinone-2-carboxylic acid (1c), adenosine, 2'-deoxyadenosine, phenylacetamide, and 2-(p-hydroxyphenyl)ethanol. The structures of these natural products were deduced from the spectral data and confirmed by comparison with related compounds from the literature and by synthesis.