Synthesis of the Oxygenated Pactamycin Core

Pactamycin, one of the most complex and densely functionalized aminocyclitol antibiotics known, presents synthetic challenges that include
reactivity and sterics, relative and absolute stereochemistry, and functional group compatibility and protection. An approach is reported that
features four different types of (cyclopentane) face selective functionalization reactions and results in a polyfunctionalized and appropriately
protected intermediate that incorporates all the core carbons and the oxygenated functionality of the target.