Concise and high‐yielding totalsyntheses of amphidinolidesT1, T3, and T4 have been completed using an alkynyl macrolactone as a common late‐stage intermediate. The required α‐hydroxy ketone motif was installed by sequential alkyne hydrosilylation, epoxidation, and Fleming–Tamao oxidation. An oxonium ylide rearrangement formed the trisubstituted tetrahydrofuran core found in the natural products.