合成路线1

Cyclization of (R)-serine methyl ester (I) with methyl benzimidate (II) gave oxazolidine (III). Reduction of the methyl ester function of (III) with LiAlH4 at low temperature afforded the hydroxymethyl derivative (IV), which was further activated as the mesylate (V). Displacement of the mesylate group of (V) with phenylpiperazine (VI) resulted in the formation of the disubstituted piperazine (VII). Nucleophilic ring opening of oxazolidine (VII) by azidotrimethylsilane yielded azide (VIII). Both the amide and azide functions of (VIII) were subsequently reduced with LiAlH4 to produce (IX). Hydrogenolysis of the benzyl amine (IX) over Pearlman's catalyst furnished the chiral ethylenediamine (X). The title imidazoline was finally obtained by cyclization of diamine (X) with methyl benzimidate (II) as its hydrochloride form in refluxing MeOH.