Polymer-Assisted solution-Phase (PASP) parallel synthesis of an α-Ketothiazole library as tissue factor VIIa inhibitors
作者:Michael S South、Thomas A Dice、Thomas J Girard、Rhonda M Lachance、Anna M Stevens、Roderick A Stegeman、William C Stallings、Ravi G Kurumbail、John J Parlow
DOI:10.1016/s0960-894x(03)00398-6
日期:2003.7
A solution-phase synthesis of an alpha-ketothiazole library of the general form D-Phe-L-AA-L-Arg-alpha-ketothiazole is described. The five-step synthesis is accomplished using a combination of polymeric reagents and polymer-assisted solution-phase purification protocols, including reactant-sequestering resins, reagent-sequestering resins, and tagged reagents. The multi-step synthesis affords the desired alpha-ketothiazole products in excellent purities and yields. A variety Of L-amino acid inputs were used to probe the S2 pocket of the tissue factor (TF) Vila enzyme to influence both potency and selectivity. An X-ray crystal structure of compound 10e bound to the TF/VIIa complex was obtained that explains the observed selectivity. The alpha-ketothiazoles were found to be potent, reversible-covalent inhibitors of tissue factor VIIa, with some analogues demonstrating selectivity versus thrombin. (C) 2003 Elsevier Science Ltd. All rights reserved.