From the oligotrophic culture of a soft coral-associated actinomycetes strain, Streptomyces sp. OUCMDZ-1703, we isolated and identified two new chlorinated polyketides that we named strepchloritides A and B （1 and 2...From the oligotrophic culture of a soft coral-associated actinomycetes strain, Streptomyces sp. OUCMDZ-1703, we isolated and identified two new chlorinated polyketides that we named strepchloritides A and B （1 and 2）, three thiazole derivatives known as watasemycin A （3）, pulicatin G （4） and aerugine （5）, along with pyrrole- 2-carboxamide, furan-2-carboxamide and 1-（3,5-dihydroxyphenyl）ethanone. The new structures of 1 and 2 were determined by spectroscopic studies such as 1D- and 2D-NMR and MS analyses, while the known compounds were identified by comparison of the NMR data with those in literatures. The results showed that actinomycete strain OUCMDZ-1703 could use the relative high ratio of chlorine in the oligotrophic medium to synthesize chlorinated natural products. New compounds 1 and 2 displayed cytotoxicity against the MCF-7 ceils with ICs0 values of 9.9 and 20.2 ~tmoloL-1, respectively. Thiazole derivatives 3 and 5 were first found to be active against three clinical strains of methicillin-resistant Staphylococcus aureus （MRSA082, MRSA111 and MRSA234） with the same MIC/MBC values of 7.81/7.81 μg·mL-1.展开更多
文摘From the oligotrophic culture of a soft coral-associated actinomycetes strain, Streptomyces sp. OUCMDZ-1703, we isolated and identified two new chlorinated polyketides that we named strepchloritides A and B （1 and 2）, three thiazole derivatives known as watasemycin A （3）, pulicatin G （4） and aerugine （5）, along with pyrrole- 2-carboxamide, furan-2-carboxamide and 1-（3,5-dihydroxyphenyl）ethanone. The new structures of 1 and 2 were determined by spectroscopic studies such as 1D- and 2D-NMR and MS analyses, while the known compounds were identified by comparison of the NMR data with those in literatures. The results showed that actinomycete strain OUCMDZ-1703 could use the relative high ratio of chlorine in the oligotrophic medium to synthesize chlorinated natural products. New compounds 1 and 2 displayed cytotoxicity against the MCF-7 ceils with ICs0 values of 9.9 and 20.2 ~tmoloL-1, respectively. Thiazole derivatives 3 and 5 were first found to be active against three clinical strains of methicillin-resistant Staphylococcus aureus （MRSA082, MRSA111 and MRSA234） with the same MIC/MBC values of 7.81/7.81 μg·mL-1.
