Total Synthesis and Structural Revision of Aeruginosin KT608A.

The synthesis of the presumed structure of aeruginosin KT608A was accomplished for the first time. The unusual d-diepi-Choi core was prepared from tyrosine via C-H activation and heterogeneous hydrogenation. Due to differences in the spectral data of synthetic and natural samples, a revised structure featuring l-diepi-Choi was proposed, which was synthesized and confirmed to be identical. On the basis of these findings, revised structures for six additional aeruginosins (KT608B, KT650, GH553, DA495A, DA511, and KB676) are presented.