Discovery of potent CCR4 antagonists: Synthesis and structure-activity relationship study of 2,4-diaminoquinazolines

A new series of quinazolines that function as CCR4 antagonists were discovered during the screening of our corporate compound libraries. Subsequent compound optimization elucidated the structure-activity relationships and led the identification of 2-(1,4'-bipiperidine-10-yl)-N-cycloheptyl-6,7-dimethoxyquinazolin-4- amine 14a, which showed potent inhibition in the [S-35] GTPcS-binding assay (IC50 = 18 nM). This compound also inhibited the chemotaxis of human and mouse CCR4-expressing cells ( IC50 = 140 nM, 39 nM). (c) 2008 Elsevier Ltd. All rights reserved.