The General Asymmetric Synthesis of Syn- and Anti-β-substituted Cysteine and Serine Derivatives

Abstract

Complete understanding of the stereochemical requirements of side chain groups important in peptide ligand-receptor/acceptor interactions plays a crucial role in the rational design of bioactive peptides and nonpeptide mimetics. This approach can be realized by incorporation of conformationally constrained novel amino acids into a peptide or nonpeptide template. Among the novel amino acids, β-substituted cysteines and β-substituted serines play a unique function in peptide conformational constraints. β-Substituted cysteines when introduced into the peptide chain can not only constrain the backbone conformation through the formation of a disulfide bridge, but also preserve side chains which are very important for molecular recognition [1]. β-Substituted cysteines and serines also can be used as building blocks for dipeptide β-turn mimetics [2].