Nonpeptide inhibitors of cathepsin G: optimization of a novel beta-ketophosphonic acid lead by structure-based drug design.
Greco, M.N., Hawkins, M.J., Powell, E.T., Almond Jr., H.R., Corcoran, T.W., de Garavilla, L., Kauffman, J.A., Recacha, R., Chattopadhyay, D., Andrade-Gordon, P., Maryanoff, B.E.(2002) J Am Chem Soc 124: 3810-3811
- PubMed: 11942800 
- DOI: https://doi.org/10.1021/ja017506h
- Primary Citation of Related Structures:  
1KYN - PubMed Abstract: 
The serine protease cathepsin G (EC 3.4.21.20; Cat G), which is stored in the azurophilic granules of neutrophils (polymorphonuclear leukocytes) and released on degranulation, has been implicated in various pathological conditions associated with inflammation. By employing high-throughput screening, we identified beta-ketophosphonic acid 1 as a moderate inhibitor of Cat G (IC(50) = 4.1 microM). We were fortunate to obtain a cocrystal of 1 with Cat G and solve its structure by X-ray crystallography (3.5 A). Structural details from the X-ray analysis of 1.Cat G served as a platform for optimization of this lead compound by structure-based drug design. With the aid of molecular modeling, substituents were attached to the 3-position of the 2-naphthyl ring of 1, which occupies the S1 pocket of Cat G, to provide an extension into the hydrophobic S3 region. Thus, we arrived at analogue 7 with an 80-fold potency improvement over 1 (IC(50) = 53 nM). From these results, it is evident that the beta-ketophosphonic acid unit can form the basis for a novel class of serine protease inhibitors.
Organizational Affiliation: 
Johnson & Johnson Pharmaceutical Research & Development, Spring House, Pennsylvania 19477-0776, USA.