Synthesis and antiallergic activity of some quinolinones and imidazoquinolinones

A group of 1,4-dihydro-4-oxoquinoline-2- and -3-carboxylic acid esters with nitrogen functionality at the 8-position was synthesized, and 6-oxo-6H-imidazo[4,5,1-ij]quinoline-4- and -5-carboxylic acid esters were elaborated from these. Several of the compounds displayed activity in the rat passive cutaneous anaphylaxis (PCA) test for antiallergic activity. However, PCA activity in this series was accompanied by rat toxicity, as measured by a decrease in percent of normal weight gain over a 2-week period, following a single oral dose.