[摘要]：A new conformationally constrained analog of glutamic acid has been synthesized efficiently in seven steps from a chiral 2-alkyl-4-piperidone. The synthesis is based on the unprecedented asym. one-carbon homologation of the ketone controlled by the size of the N-substituent and the appropriate manipulation of substituents at positions 2 and 4 of the piperidine ring, a step that involves two independent oxidn. processes.
