Benzothioate Glycoside from a terrestrial Streptomyces sp. TBRC 11511 from Thailand.

A new benzothioate glycoside metabolite, phitsanoside A, together with its new and known derivatives were isolated from Streptomyces sp. TBRC 11511 collected from sediment of a dry evergreen forest located in Phitsanulok Province, Thailand. The structure elucidation of the new compound was interpreted on the basis of spectroscopic data analysis. The configuration of the sugar moiety was derived based on NOESY nuclear magnetic resonance correlations, a vicinal coupling constant analysis, and the measurement of an optical rotation from the hydrolyzed sugar unit, which was identified as β-D-glucopyranose. Phitsanoside A did not exhibit antibacterial activity against Bacillus cereus, Mycobacterium tuberculosis or Staphylococcus aureus, but phitsanoside B showed activity against all of them with MIC values of 3.13, 25 and 12.5 μg ml-1, respectively.