合成路线1

The title compound is prepared by solid phase synthesis employing a Rink amide resin. Acylation of the resin with chloroacetyl chloride (I) affords the chloroacetyl resin (II). Subsequent chloride displacement with s-butylamine (III) provides the aminoacid-bound resin (IV). A new acylation of (IV) with chloroacetyl chloride (I) yields the chloroacetamide (V), which is then displaced by cyclopropylamine (VI), yielding the dipeptide derivative (VII). Then, a further coupling of (VII) with acid chloride (I), followed by displacement of the resultant chloroacetamide resin (VIII) with N-(2-aminoethyl)pyrrolidine (IX) gives rise to the tripeptide resin (X). Finally, cleavage of the dipeptide amide from the solid support is accomplished by treatment with trifluoroacetic acid in CH2Cl2