Isolation and Structure Elucidation of Cytotoxic Saccharothriolides D to F from a Rare Actinomycete Saccharothrix sp. and Their Structure Activity Relationship.
Three new 10 membered macrolides, saccharothriolides D F (1 3) were isolated from a rare actinomycete, Saccharothrix sp. A1506. The planar structures were determined from analysis of extensive NMR and HR ESI MS data, and the absolute configurations were established by ECD spectroscopy analysis. Saccharothriolides D (1) and E (2) were determined to be C 2 epimers of saccharothriolides A (4) and B (5) respectively. Saccharothriolide F (3) was identified to be a demethylated congener of saccharothriolides D (1) and A (4) at the C 2 position. The availability of compounds 1 6 enabled a structure activity relationship study that revealed the importance of the phenolic hydroxy group at C 2' and the stereochemistry of C 2 for the inhibition of human fibrosarcoma HT1080 cell growth.
Journal of natural products