Nonpeptidic chymase inhibitors: design and structure-activity relationships of pyrimidinone derivatives based on the predicted binding mode of a peptidic inhibitor.

While the biological reaction of chymase have been often studied for ten years, the pathophysiological role of chymase has not been fully elucidate due to a lack of effective inhibitors featuring potent inhibitory activity, specificity, and metabolic stability. Recently the discovery of a structurally varied range of novel nonpeptidic inhibitors presents new opportunities to explore the role of chymase under both physiological and pathophysiological conditions and to develop therapeutic agents for chymase-induced diseases. In this article the structure and the inhibitory mechanism of nonpeptidic chymase inhibitors are discussed, with special emphasis on design and structure-activity relationships of pyrimidinone derivative where inhibitory activity, protease selectivity, and pharmacokinetic profile are clarified.