Stereoselective Synthesis of Protected 12‐Membered Macrolide Antibiotic 13 E ‐Disciformycin B Aglycone

A stereoselective synthesis of protected macrocyclic lactone core structure of 13 E ‐disciformycin B was accomplished in a convergent fashion employing commercially available (4 S ,5 S )‐2,2‐dimethyl‐1,3‐dioxolane‐4,5‐dicarboxylate, tiglic aldehyde and ( R )‐Roche ester. Key transformations include an Aldol reaction, CBS reduction, Takai olefination, Julia olefination, Nozaki–Hiyama–Kishi (NHK) reaction, and Yamaguchi esterification reaction.