Asymmetric Synthesis of Peptides

Production of optically pure d- and l-α-amino acids by Bioconversion of d,l-5-monosubstituted hydantoin derivatives

“…Furthermore, synthetic strategies for the construction of the C-5 substituent may predetermine the method of choice. For example, an indolylmethylene side chain may be introduced into the hydantoin ring by substitution of the C-5 position with indole-3-aldehyde, but also by the Bucherer-Bergs synthesis using phenylhydrazine as precursor of the indole ring [15][16][17][18] Thus, the s-carbon atom of the amino acids forms the C-5 position of the hydantoin ring. It has occasionally been found advantageous to use instead of s-amino acids their amides or nitriles; especially the latter could efficiently be reacted with carbon dioxide under pressure.…”