SemiautomatedTotal Synthesis of the Cyclic LipodepsipeptideAnikasin

The total synthesis of <i>Pseudomonas</i>-derived cyclic lipodepsipeptide anikasin was achieved. Using a depsipeptide building block and balanced protecting groups on the branching d-<i>allo</i>-Thr residue, the synthesis was established semiautomatically on a synthesizer. Buffered deprotections minimized side reactions and afforded synthetic anikasin and its enantiomer. Biological activity studies indicated that anikasin’s mode of action is directly resulting from its physicochemical properties.