合成路线1

The title compound was prepared by solid-phase synthesis using a 2-chlorotrityl resin, chloride form. N2-(Benzyloxycarbonyl)-L-2,3-diaminopropionic acid (I) was protected as the Fmoc derivative (II) upon treatment with N-(Fmoc-oxy)succinimide. After attachment of the protected diaminoacid (II) to the chloride resin, the Fmoc group was selectively removed by means of piperidine in DMF to give the resin-bound Cbz-2,3-diaminopropionic acid (III). Acylation of the free amino function of (III) with 4-(chloromethyl)benzoyl chloride (IV) provided amide (V). The chloride group of (V) was then displaced with 2-(aminomethyl)benzimidazole (VI), yielding resin (VII). The required urea functionality (IX) was obtained by coupling (VII) with cyclohexyl isocyanate (VIII). Finally, cleavage of the carboxylic acid from the resin (IX) was achieved by treatment with trifluoroacetic acid in moist dichloromethane.