AbstractThe first total synthesis of the allene-containing cyclic tetrapeptide pseudoxylallemycin C is reported. The Tyr(t-Bu)-protected linear peptide was prepared on-resin and cyclized in solution phase to yield the protected cyclic precursor. Upon deprotection of Tyr(t-Bu), the desired phenolic cyclic tetrapeptide was separated by RP-HPLC from its epimer that also formed during the macrocyclisation step. Subsequent alkylation with 4-bromobuta-1,2-diene yielded pseudoxylallemycin C.