Synthesis and anticonvulsant properties of 2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]benzimidazol-1-one derivatives.

A number of novel 1H-pyrrolo[1,2-a]benzimidazol-1-one derivatives were prepared and their anticonvulsant properties evaluated. The new synthesized compounds proved to possess anticonvulsant effects depending on the nature of substituents at C-6, C-2, and C-3a positions of the polycyclic system. In particular, the 6-chloro-3a-(p-tolyl)-2,3,3a,4-tetrahydro-1H-pyrrolo[1,2-a]benzimidazol-1-one derivative (22) displayed potency fivefold higher than unsubstituted compound (13).