An efficient two-step synthesis of mono-, di- and triureas from resin-bound amides

An efficient method for the solid-phase synthesis of mono-, di- and triureas from resin-bound monoamines, diamines and triamines is described. The exhaustive reduction of solid support-bound amides generated the requisite amines, which, following treatment with isocyanates and cleavage, provided the corresponding ureas in high purity and good yields.