ABSTRACT
The first total synthesis of elmonin and pratenone A, two complex rearranged angucyclinones from Streptomyces, is reported. Using peri-directed C-H functionalization, the key naphthalene fragment present in both synthetic targets was efficiently prepared. Coupling to two anisole-derived fragments gave access to the natural products, in which elmonin was prepared using a biomimetic spiro-ketalization.
Subject(s)
Biological Products , Streptomyces , BiomimeticsABSTRACT
The regular bicyclic spiro motif is highly abundant given its synthetic accessibility while the diastereomer-virtually obtained through inversion at the central atom-is almost unknown. We have developed methodology to access the elusive inverted spiro architecture by employing a covalent template-directed approach. Comparison with the regular spiro bicycle analog unequivocally established the diastereomeric relationship, providing insight into the fascinating stereochemical and structural properties.