Synthesis of the Peptaibol Framework of the Anticancer Agent Culicinin D: Stereochemical Assignment of the AHMOD Moiety

The postulated structure of the potent anticancer peptaibol culicinin D has been synthesized using Fmoc-based solid-phase peptide synthesis (SPPS). Comparison of the (1)H NMR data for the reported structure of culicinin D with the data obtained for the two synthetic polypeptides epimeric at C-6 in the AHMOD unit established the C-6 stereochemistry of the AHMOD residue in the natural product to be (R).