Investigations into the synthesis of oxathiocoraline, a bicyclic depsipeptide with C2 symmetry, revealed a number of unexpected side-reactions that could not be circumvented by classical or standard means. This cyclodepsipeptide has a large number of N-methyl amino acids coexisting with two ester bonds and also shows a branched structure; these features hinder its synthesis. In addition, complexity
Micromonospora sp. This symmetricbicyclic depsipeptide binds the minor groove of DNA. Here we report two solid-phase strategies for the syntheses of azathiocoraline and its analogues. The thioester linkage was replaced by an amide bond to improve the compound's pharmacokinetic properties. The first strategy is based on a convergent (4+4) approach, whilst the second is a stepwise synthesis, cyclizations in