Total synthesis of RK-397

An enantioselective synthesis of the polyene macrolide RK-397 is described. The use of the same eight-carbon building block twice for the construction of the polyol chain allowed for a highly convergent synthesis. The synthesis highlights stereoselective vinylogous aldol addition using a chiral bisphosphoramide as well as a sequential palladium-catalyzed cross-coupling reaction for the preparation of key fragments.