Isolation and structure elucidation of satosporin A and B: new polyketides from Kitasatospora griseola.

Satosporins A and B, two novel glucosylated polyketides, were isolated from the actinomycete Kitasatospora griseola MF730-N6. The polyketides possess an unprecedented tricyclic ring system that was fully characterized using a combination of spectroscopic analyses and computational calculations. Satosporin A was quantitatively converted into its aglycon homologue, satosporin C, using a β-glucosidase. The determination of the absolute stereochemistry was achieved using solution TDDFT/ECD calculations and chemical derivatization methods.