Perhydropyrrolo[1,2-c]imidazole-1,3-dione (II) was prepared by Urech synthesis upon condensation of proline (I) with potassium cyanate, followed by acid cyclization. Subsequent alkylation of (II) with 1-bromo-4-chlorobutane (III) in the presence of NaH in DMF provided the chlorobutyl derivative (IV). This was finally coupled with aryl piperazine (V) to yield the title compound.

The condensation of perhydropyrrolo[1,2-c]imidazole-2,7-dione (I) with 1,4-dibromobutane (II) by means of NaH in DMF gives the expected 4-bromobutyl derivative (III), which is condensed with 1-(3-nitrophenyl)piperazine (IV) by means of triethylamine in hot acetonitrile yielding 2-[4-[4-(3-nitrophenyl)piperazin-1-yl]butyl]perhydropyrrolo[1,2-c]imidazole-2,7-dione (V). The reduction of the nitro group of (V) with H2 over Pd/C in methanol affords the corresponding amino derivative (VI), which is finally sulfonated with ethanesulfonyl chloride and pyridine in acetone.