Caryolanes, known as β-caryophyllene alcohols, are widely occurring sesquiterpenes in plants. From the cultures of marine Streptomyces sp. AH25, two new caryolane sesquiterpenes, micaryolanes A and B (1 and 2), together with caryolan-1,9β-diol (3) were isolated. Their structures were elucidated by extensive analyses of HR-MS and NMR spectroscopic data. The absolute configurations were assigned via the CD data of the in situ formed [Rh2 (OCOCF3 )4 ] complex and supported by comparison of experimental and calculated specific rotation values. Compounds 1-3 exhibited no activities against Hep3B or MG-63 cell lines or against Gram-positive and Gram-negative bacteria. The results not only enriched the caryolane family, but also proved bacteria as a productive source of terpene metabolites.
Keywords: Streptomyces; bacterial terpene; caryolane; sesquiterpene; β-caryophyllene alcohol.
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