Discovery of 3-piperidinyl-1-cyclopentanecarboxamide as a novel scaffold for highly potent CC chemokine receptor 2 antagonists.

Introduction of ring restrictions to a linear aminobutyramide CC chemokine receptor 2 (CCR2) antagonist lead (2) led to the discovery of a 1,3-disubstituted cyclopentane scaffold with enhanced hCCR2 receptor binding and antagonist activity. (1S,3R)-N-[3,5-Bis(trifluoromethyl)benzyl]-1-methyl-3-[(1R,3'R)-methyl-1'H-spiro[indene-1,4'-piperidin]-1'-yl]cyclopentanecarboxamide (16) had IC50 of 1.3 nM (binding) and 0.45 nM (functional chemotaxis) against hCCR2. It also showed activity against the mouse CCR2 receptor with an IC50 of 130 nM. Compound 16 is selective against other chemokine receptors, including CCR5 ( approximately 500-fold).