Some new substituted coumarinylthiazolines, coumarinylthiazolidin-4-ones, and substituted chromenothiazoles were synthesized and evaluated for anticonvulsant activity. Some selected compounds were assayed against seizures induced by pentylenetetrazole (PTZ) and strychnine in mice. Compounds 3b, 6b, and 7b were the most active of the series against PTZ induced seizures. Compound 7b provided anticonvulsant activity (PD(50)=95mg/kg, ip) at a dose 200mg/kg compared to phenobarbital (PD(50)=16mg/kg, ip) at a dose 30mg/kg (90% protection). No clear correlation was observed between the antiepileptic activity and molecular lipophilicity descriptors of the tested compounds.