Solid-phase synthesis of oligourea peptidomimetics employing the Fmoc protection strategy

A solid-phaseFmoc-basedsynthesis strategy is described for oligourea peptidomimetics as well as a convenient general synthesis approach for the preparation of the required building blocks 5a−j and 5k. These are suitable for use in peptide or robot synthesizers, which is illustrated by the synthesis of oligourea peptidomimetics of part of Leu-enkephalin (10) and a neurotensin derivative (17)