Synthesis and CNS activity of new 1-alkyl-2-aryl-7-hydroxy-5(1H)oxo-imidazo[1,2-a]pyrymidines.

Cyclocondensation of 1,5-disubstituted 2-aminoimidazolines with diethyl malonate in the presence of sodium methanolate leading to imidazol[1,2-alpyrimidine-5,7-dion system is presented. Prevailing of 7-hydroxy-5(1H)oxo form between three possible tautomers is discussed based on spectral data. CNS activity of nine compounds is evaluated.