A Total Synthesis of the Cyclic Depsipeptide Chaiyaphumine-A

The first total synthesis of Chaiyaphumine-A, a cyclic depsipentapeptide isolated from Xenorhabdus SP. PB614 which showed good activity against Plasmodium falcifarum (IC50 = 0.61M) has been described. The synthesis of Chaiyaphumine-A was accomplished by solution phase fragment synthesis using protection, deprotection, coupling and cyclisation reactions. Five amino acids viz. L-Threonine, D-phenyl alanine, D-Alanine, L-Proline and L-Tryptophan are assembled together by amide coupling reactions. The macrocylization of side chain (-OH) of L- Thr and C-terminus of carboxylic acid from L-Tryptophan to give Chaiyaphumine-A in 12% yield. The spectroscopic data (H-1-NMR, C-13-NMR, HRMS) confirmed the structure elucidation as reported in literature.