Publications by authors named "Keith A M Walker"

Identification of singleton P2X7 inhibitor 1 from HTS gave a pharmacophore that eventually turned into potential clinical candidates 17 and 19. During development, a number of issues were successfully addressed, such as metabolic stability, plasma stability, GSH adduct formation, and aniline mutagenicity. Thus, careful modification of the molecule, such as conversion of the 1,4-dihydropyridinone to the 1,2-dihydropyridinone system, proper substitution at C-5″, and in some cases addition of fluorine atoms to the aniline ring allowed for the identification of a novel class of potent P2X7 inhibitors suitable for evaluating the role of P2X7 in inflammatory, immune, neurologic, or musculoskeletal disorders.

View Article and Find Full Text PDF

Two distinct synthetic schemes were applied to access heteroatom-containing alpha-chain lactams or lactams terminated as aryl acids. The latter lactams were devised using a pharmacophore for EP(4) receptor activity. gamma-Lactams were characterized for their prostanoid EP receptor affinities and EP(4) activity and found to be selective for the EP(2) and EP(4) receptors or selective for the EP(4) subtype.

View Article and Find Full Text PDF

The introduction of 3-arylmethyl, 3-aryloxy and 3-arylthio moieties into a 6-methylsulfonylindole framework using rational drug design led to potent, selective COX-2 inhibitors having efficacy in a rat carrageenan air pouch model. Incorporation of a conformationally more rigid 3-aroyloxy substituent onto the 6-methylsulfonylindole scaffold led to selective, but considerably less potent COX-2 inhibitors. Variation of the hydrophilicity and size of the indole 2-substituent of 3-arylthio-6-methylsulfonylindole inhibitors led to modulation of the COX-2 human whole blood (HWB) potency and selectivity.

View Article and Find Full Text PDF

A novel series of TNF inhibitors was identified based on the screening of existing MMP inhibitor libraries. Further SAR optimization led to the discovery of a novel lead compound. Its synthesis, efficacy in experimental animal models, and pharmacokinetic data are discussed.

View Article and Find Full Text PDF

Optimization of the amino acid side chain and the N-alkyl group of the sulfonamide of amino acid derived sulfonamide hydroxamates is discussed. The solid-phase synthesis of these potent inhibitors of procollagen C-proteinase (PCP) is presented. In addition, novel carboxylic acid sulfonamides were discovered to be PCP inhibitors.

View Article and Find Full Text PDF