Abstract:
2-Amino-5-(heteroarylmethylene)-1,3,4-oxadiazoles/thiadiazoles 7−10 were synthesized by cyclisation of 1-(heteroarylacetyl)semicarbazides/thiosemicarbazides 3−6. 5-(2’-Heteroarylmethylene-5’-aminomethylene-1’, 3’, 4’-oxadiazol-2’-yl/ thiadiazol-2’-yl)-2-oxo/thiobarbituric acids 11−18 were synthesized by condensation of compounds 7−10 at the 5th position of 2-oxo/thiobarbituric acids. The newly synthesized compounds showed anticonvulsant activity ranging from 50–90 % (seizures protection). Compound 18 (5-(2’-phenothiazinylmethylene-5’-aminomethylene-1’,3’,4’-thiadiazol-2’-yl)-2-thiobarbituric acid) showed maximum activity being more potent than the reference drug phenytoin sodium (CAS 630-93-3)