597584-73-1Relevant articles and documents
A novel class of nonpeptidic biaryl inhibitors of human cathepsin K
Robichaud, Jo?l,Oballa, Renata,Prasit, Peppi,Falgueyret, Jean-Pierre,Percival, M. David,Wesolowski, Gregg,Rodan, Sevgi B.,Kimmel, Donald,Johnson, Colena,Bryant, Cliff,Venkatraman, Shankar,Setti, Eduardo,Mendonca, Rohan,Palmer, James T.
, p. 3709 - 3727 (2007/10/03)
A novel series of nonpeptidic biaryl compounds was identified as potent and reversible inhibitors of cathepsin K. The P2-P3 amide bond of a known amino acetonitrile dipeptide 1 was replaced with a phenyl ring, thereby giving rise to this biaryl series that retained potency vs cathepsin K and showed an improved selectivity profile against other cathepsins. Structural modification within this series resulted in the identification of compound (R)-2, a potent human cathepsin K inhibitor (IC50 = 3 nM) that is selective versus cathepsins B (IC50 = 3950 nM), L (IC50 = 3725 nM), and S (IC50 = 2010 nM). In an in vitro assay involving rabbit osteoclasts and bovine bone, compound (R)-2 inhibited bone resorption with an IC 50 of 95 nM. It was shown that, unlike some peptidic nitrile inhibitors of cysteine proteases, the nitrile moiety of (R)-2 is not converted to the corresponding amide 3 by cathepsin K. This indicates that this class of nonpeptidic nitrile inhibitors is unlikely to be hydrolyzed by cysteine proteases. Furthermore, the inhibition of cathepsin K by compound (R)-2 was shown to be fully reversible and not observably time-dependent. To demonstrate the efficacy of compound (R)-2 in vivo, it was administered to ovariectomized (OVX) rhesus monkeys at 20 mg/kg, po once daily for 8 days, and a urinary marker of bone turnover, N-telopeptide of type I collagen (uNTx), was measured. During the eight-day dosing period, the mean reduction by compound (R)-2 in uNTx was 80% (p 0.001). This demonstrates that inhibition of cathepsin K leads to an inhibition of this bone resorption marker in OVX rhesus monkeys and strongly suggests that inhibition of cathepsin K is a viable therapeutic approach for the treatment of osteoporosis.
