Total Synthesis of Divergolides E and H.

This manuscript describes the first total syntheses of divergolides E and H. The route employs a telescoped hetero-Diels-Alder and oxidative carbon-hydrogen bond cleavage as an entry into the central bridged bicyclic acetal unit. Additional key steps of the highly convergent route include a desymmetrizing epoxidation, a chelation-controlled alkenylzinc addition, an amide formation between a hindered aniline and an acylating agent that is prone to ketene formation, and a challenging macrolactonization.