合成路线1

The hydrolysis of 7-bromoheptanenitrile (I) with HCl gives the corresponding amide (II), which is treated with Na-N3 in hot DMSO to yield 7-azidoheptanamide (III) (1). The condensation of (III) with 2-hydroxy-2-methoxyacetic acid methyl ester (IV) in hot dichloromethane affords the alpha-hydroxyglycine (V), which is treated with SOCl2 in the same solvent to provide the alpha-chloroglycine (VI). The reaction of (VI) with benzyl alcohol and TEA in dichloromethane furnishes the benzyloxy derivative (VII), which is hydrolyzed at the ester group by means of NaOH in DME to give the carboxylic acid (VIII). The condensation of (VIII) with N1,N4-bis(benzyloxycarbonyl)spermidine (IX) by means of DCC and HOBt in dichloromethane yields the corresponding amide (X), which is reduced at the terminal azido group by means of PPh3 in THF/water, affording the expected primary amine (XI). The condensation of (XI) with the protected isothiourea (XII) in THF affords the protected guanidine derivative (XIII), which is finally deprotected by hydrogenolysis with H2 over Pd(OH)2 in methanol/acetic acid to provide the target compound.