Syntheses of Prekinamycin and a Tetracyclic Quinone from Common Synthetic Intermediates

Towards total synthesis of a series of kinamycin and related antibiotics via common synthetic intermediates, total synthesis of prekinamycin was achieved via Suzuki coupling of naphthaleneboronic acid and bromobenzene derivative, intramolecular FriedelCrafts reaction of 2-(naphthalen-2-yl)benzoic acid, and diazotization in ten steps from 3,5-dimethylphenol. Synthetic studies towards kinamycin antibiotics was also examined, and the tetracyclic quinone core for kinamycins was synthesized. Palladium-catalyzed site-selective hydroxylation of a benzoic acid derivative with the AB-D ring part was successfully applied to the selective D-ring functionalizations.