ANTICONVULSANT ACTIVITY OF PYRROLO[1',2'-1,2]IMIDAZO[4,5-B]PYRIDINES,PYRROLO[2',1'-2,3]IMIDAZO[4,5-C] PYRIDINES AND PYRROLO[2,1-F]PURINES IN DBA 2 MICE/

1. The behavioural and anticonvulsant effects of eight pyrrolimidazopy ridines (PI(1)a-d and PI(2)a-d) and four pyrrolopurines (PP) were stud ied after intraperitoneal administration in DBA/2 mice, a strain genet ically susceptible to sound-induced seizures. 2. The anticonvulsant ef fects were evaluated in DBA/2 mice on seizures evoked by means of audi tory stimulation (109 dB, 12-16 kHz) in animals placed singly under a perspex dome. 3. Hypothermic activity was observed after the highest d oses of the pyrroloderivatives studied. 4. Our study demonstrated that the anticonvulsant effect of pyrroloimidazopyridines H-pyrrolo-[1',2' :1,2]imidazo[4,5-b]pyridin-6-ones) and pyrrolopurines (PP) was general ly better than corresponding pyrrolobenzimidazoles (PB) and pyrroloimi dazopyridines 8H-pyrrolo[2',1':2,3]imidazo[4,5-c]pyridin-8-ones) and, in some cases, comparable to that of phenytoin and desmethylclobazam. 5. The anticonvulsant potency of the derivatives studied cannot be dir ectly related to their lipophilicity.