Design and Synthesis of Thrombin Inhibitors: Analogues of MD-805 with Reduced Stereogenicity and Improved Potency
作者:Derek Brundish、Alice Bull、Vera Donovan、Joseph D. Fullerton、Sheila M. Garman、Judy F. Hayler、Diana Janus、Peter D. Kane、Mark McDonnell、Garrick P. Smith、Robert Wakeford、Clive V. Walker、Graham Howarth、William Hoyle、Mark C. Allen、John Ambler、Keith Butler、Mark D. Talbot
DOI:10.1021/jm9811209
日期:1999.11.1
Mitsubishi's MD-805, a potent and selective inhibitor of thrombin which contains four stereogenic centers, has been the starting point for an optimization program. A systematic synthetic study resulted in thrombin inhibit;ors achiral at P2 and P3 but with a 10-fold increase in potency over the original lead. A number of 4-substituted piperidines were synthesized and examined as replacements for 2-carboxy-4-methylpiperidine at P2; 4-fluoroethylpiperidine (FEP) among others provided inhibitors (e.g. 45g) of increased potency. An enantioselective route was developed to 3(R)-methyl-1,2,3,4-tetrahydroquinolinesulfonyl chloride. Inhibitors containing this enantiomerically pure P3 (42d) had similar potency to the racemic material and provided support, with modeling studies, for the preparation of the gem 3,3-disubstituted compounds. A series of inhibitors containing the novel 3,3-dimethyl-1,2,3,4-tetrahydroquinolinesulfonyl (DMTHQS) P3 (Table 5) were synthesized and showed a similar activity profile as the monomethyl series. The combination of P3-DMTHQS, PB-FEP, and P1-arginine (45g) had a K-i of 6 nM (MD-805 K-i = 85 nM). In animal models of both venous and arterial thrombosis, one inhibitor (42e) was shown to produce a dose-dependent inhibition of thrombus formation that in some situations was superior to that of MD-805.