Synthesis, structure, and biological activity of 4-hetaryl-2-pyrrolidones containing a pyrazole ring.

Unlabelled: Single diastereomers of 4-hetaryl-2-pyrrolidone-3(5)-carbo- and 2-[4-hetaryl-2-pyrrolidon-1-yl]acetohydrazides were used in reactions with 2,4-pentanedione, providing (3,4)-3-, (4,5)-5-(3,5-dimethyl-1-pyrazole-1-carbonyl)- and 1-[2-(3,5-dimethyl-1-pyrazol-1-yl)-2-oxoethyl]-4-hetaryl-2-pyrrolidones. The structures of the synthesized compounds were confirmed by spectral methods and X-ray structural analysis. Some of the obtained compounds were shown to possess nootropic and anxiolytic activity.