Total Syntheses of Disorazoles A₁ and B₁ and Full Structural Elucidation of Disorazole B₁

Described herein are the first total syntheses of naturally occurring antitumor agents disorazoles A1 and B1 and the full structural assignment of the latter. The syntheses were achieved through convergent strategies employing enantioselective constructions of the required building blocks, including a novel Sharpless epoxidation/enzymatic kinetic resolution of stannane-containing substrates that led selectively to both enantiomeric forms of an epoxy vinyl stannane, and a series of coupling reactions, including a Wittig reaction, a Suzuki coupling, a Stille coupling, a Yamaguchi esterification and a Yamaguchi macrolactonization.