Antiallergy agents. I. 1,6-dihydro-6-oxo-2-phenylpyrimidine-5-carboxylic acids and esters

Article abstract of DOI:10.1021/jm00189a009

The synthesis of some 1,6-dihydro-6-oxo-2-phenylpyrimidine-5-carboxylic acids and esters with potent oral and intravenous antiallergic activity against passive cutaneous anaphylaxis in the rat is described. Requirements for high activity include a free NH group in the pyrimidinone nucleus and a small to medium size ortho alkoxy or alkenyloxy group on the phenyl ring. It is suggested that in the case of the highly active compounds hydrogen bonding occurs between a nitrogen of the pyrimidine ring and the ethereal oxygen. The nature of this bonding and its possible contribution to an optimum configuration for the molecules is discussed.