Concise total synthesis and structure revision of metacridamides A and B

Abstract

Concise total synthesis of metacridamides is accomplished, resulting in the revision of the absolute configuration of the C-9 position.

Macrocyclization strategies for the total synthesis of cyclic depsipeptides

“…57 Recently, ynamides were used for macrolactonization when traditional esterification conditions were unsuccessful for the total synthesis of metacridamides A and B. 58 Another example was a Ag( i )-promoted conversion of thioamide peptide to an isoimide, which undergoes an acyl transfer to the β-hydroxyl group of Ser/Thr sidechain, leading to a ring expansion of 2 atoms was recently developed and the total synthesis of teixobactin, seongsanamide E and kahalalide B were accomplished in this manner, with around 30% yield for the macrocyclization step. 59 While effective, this method does require the synthesis of the thioamide linkage for the Ser/Thr residue involved in macrolactonization.…”