合成路线1

The hydrolysis of the 1-isopentyl-4-nitro-1H-pyrrole-2-carboxylic acid ethyl ester (I) with NaOH in hot ethanol gives the carboxylic acid (II), which is treated with refluxing SOCl2 to yield the acyl chloride (III). The reaction of (III) with 3-aminopropionitrile (IV) in toluene affords the carboxamide (V), which is treated with ethylamine (VI) and HCl in ethanol to provide the N-ethylamidino derivative (VII). The reduction of the nitro group of (VII) with H2 over Pd/C in methanol gives the aminopyrrole (VIII), which is finally condensed with bis pentafluorophenyl terephthalate (XI) to afford the target terephthalamide. The activated ester bis pentafluorophenyl terephthalate (XI) has been obtained by esterification of terephthalic acid (IX) with pentafluorophenyl trifluoroacetate (X) by means of DIEA in DMF.