Donghaesulfins A and B, Dimeric Benz[a]anthracene Thioethers from Volcanic Island Derived Streptomyces sp.

Abstract

The chemical analysis of a Streptomyces strain, from a Korean volcanic island, discovered new benz­[a]­anthracene dimers linked by a thioether bond. The structures of donghaesulfins A and B (1 and 2) were elucidated by spectroscopic analysis including energy-dispersive X-ray. Their configurations were determined by ROESY NMR data, DP4 calculations, the modified Mosher’s method, and ECD calculations. Donghaesulfins A (1) induced quinone reductase, whereas donghaesulfin B (2) displayed antiangiogenesis activity.

Donghaecyclinones A–C: New Cytotoxic Rearranged Angucyclinones from a Volcanic Island-Derived Marine Streptomyces sp.

“…The isolation and phylogenetic analysis of the Streptomyces sp. bacterial strain SUD119 were previously reported [18]. Strain SUD119 was inoculated in 50 mL of YEME medium (4 g of yeast extract, 10 g of malt extract, and 4 g of glucose in 1 L of artificial seawater) in a 125 mL Erlenmeyer flask.…”

“…The fraction collected at 20.4 min contained donghaecyclinones B and C (2 and 3), and the other major fraction obtained at 38.6 min was composed of pure donghaecyclinone A (1, 4.2 mg). The mixture of donghaecyclinones B and C (2 and 3) was further purified using an isocratic HPLC solvent system (48% MeOH/H 2 O, UV detection at 280 nm, flow rate: 2 mL/min) using a reversed-phase C 18 HPLC column (Kromasil C 18 (2): 250 mm × 10 mm, 5 µm). Donghaecyclinones B and C (2 and 3) were acquired at retention times of 28.2 min (3.5 mg) and 31.6 min (4.1 mg), respectively.…”

“…The inhibitory activities of donghaecyclinones A-C (1-3) were evaluated against Gram-positive bacteria (Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, Streptococcus pyogenes ATCC 19615, and Kocuria rhizophila NBRC 12708) and Gram-negative bacteria (Klebsiella pneumoniae ATCC 10031, Salmonella enterica ATCC 14028, Escherichia coli ATCC 25922, and Proteus hauseri NBRC) using the previously reported method [18].…”

“…Trichophyton mentagrophytes IFM 40996, Trichophyton rubrum NBRC 9185, Aspergillus fumigatus HIC 6094, and Candida albicans ATCC 10231 strains were used to measure the antifungal activities of donghaecyclinones A-C (1-3) by following the previously reported procedure [18].…”

“…In this regard, we have been examining the chemical profiles of actinobacterial strains that inhabit the marine environments of volcanic islands, which may provide unique microbial habitats with volcanic minerals and salts from the surrounding seawater [11]. This has led to the successful discovery of various classes of new natural products [12][13][14][15][16][17][18] from volcanic island-derived marine actinomycetes. These include new cyclic peptides with anticancer and antituberculosis activities, ohmyungsamycins A and B [12], new anti-inflammatory linear polyketides, succinilenes A-D [17], and donghaesulfins A and B, which are dimeric benz[a]anthracenes linked through a sulfide bond [18].…”