A highly stereoselective synthesis of the novel tryptase inhibitor BMS-262084 was developed. Key to this synthesis was the discovery and development of a highly diastereoselective demethoxycarbonylation of diester 12 to form the trans-azetidinone 13. BMS-262084 was prepared in 10 steps from D-ornithine in 30% overall yield.
Process Research and Development, Bristol-Myers Squibb Pharmaceutical Research Institute, 1 Squibb Drive, P.O. Box 191, New Brunswick, NJ 08903-0191, USA. xinhua.qian@bms.com