Enantio- and diastereoselective syntheses of cyclic Cα-tetrasubstituted α-amino acids and their use to induce stable conformations in short peptides

Cα‐Tetrasubstituted α‐amino acids are widely used to design and prepare peptides and peptide mimics with constrained conformations. Subcategories of these compounds are cyclic Cα‐tetrasubstituted α‐amino acids, in which both α‐substituents are covalently connected. This survey presents recent advances in the synthesis and application of cyclic Cα‐tetrasubstituted α‐amino acids in a systematic order beginning with cyclopropane amino acids, continuing with four, five, six membered rings, and ring structures larger than six‐membered. We discuss synthetic routes to the cyclic Cα‐tetrasubstituted α‐amino acids and their use as conformation determining elements in peptides. © 2007 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 90: 8–27, 2008. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com