Synthesis and evaluation of Aza HUN-7293

The aza analogue of the cyclic heptadepsipeptide HUN-7293 (1), which is a potent naturally occurring inhibitor of inducible cell adhesion molecule expression, and its C23 (MLEU3 C2) epimer were prepared via solution-phase synthesis. Biological evaluations of these two compounds as inhibitors of cell adhesion molecules expression are detailed.