(+)-SCH 351448 possesses a very interesting and unique structure. It features a 28-membered macrodiolide consisting of two identical hydroxyl carboxylic acid units, and comprises four cis-2,6-disubstituted tetrahydropyran rings with opposite relative stereochemistry on each half of the molecule. Such symmetrical architecture allows a highly convergent disconnection approach into a monomeric unit 1 as depicted in Scheme 1. This is also the target molecule in our ...