Formal synthesis of cyclotheonellazole A.

A convergent procedure for the formal synthesis of cyclotheonellazole A in high yields and excellent stereoselectivity has been developed. This synthesis features an efficient preparation of O -pivaloyl-protected α-hydroxy-β-amino amides and a one-pot process to introduce the challenging thiazole moiety. The overall synthesis is very efficient and paves the way for the preparation of analogues for drug development.