Document Report Card

ID: ALA1140150

Journal: J Med Chem

Title: Identification of a nonbasic, nitrile-containing cathepsin K inhibitor (MK-1256) that is efficacious in a monkey model of osteoporosis.

Authors: Robichaud J, Black WC, Thérien M, Paquet J, Oballa RM, Bayly CI, McKay DJ, Wang Q, Isabel E, Léger S, Mellon C, Kimmel DB, Wesolowski G, Percival MD, Massé F, Desmarais S, Falgueyret JP, Crane SN.

Abstract: Herein, we report on the identification of nonbasic, potent, and highly selective, nitrile-containing cathepsin K (Cat K) inhibitors that are built on our previously identified cyclohexanecarboxamide core structure. Subsequent to our initial investigations, we have found that incorporation of five-membered heterocycles as P2-P3 linkers allowed for the introduction of a methyl sulfone P3-substitutent that was not tolerated in inhibitors containing a six-membered aromatic P2-P3 linker. The combination of a five-membered N-methylpyrazole linker and a methyl sulfone in P3 yielded subnanomolar Cat K inhibitors that were minimally shifted (<10-fold) in our functional bone resorption assay. Issues that arose because of metabolic demethylation of the N-methylpyrazole were addressed through introduction of a 2,2,2-trifluoroethyl substituent. This culminated in the identification of 31 (MK-1256), a potent (Cat K IC 50 = 0.62 nM) and selective (>1100-fold selectivity vs Cat B, L, S, C, H, Z, and V, 110-fold vs Cat F) inhibitor of cathepsin K that is efficacious in a monkey model of osteoporosis.

CiteXplore: 18811135

DOI: 10.1021/jm800610j