Synthesis of fluorescent enone derived alpha-amino acids.

The development of a facile and general method for the preparation of enone derived alpha-amino acids is described. The key step involves a Horner-Wadsworth-Emmons reaction between an aspartic acid derived beta-keto phosphonate ester and a range of aldehydes resulting in the formation of highly functionalised alpha-amino acids in good yields. An efficient two-stage deprotection process using mild conditions was developed to give the parent alpha-amino acids. Application of this methodology has produced a novel fluorescent alpha-amino acid that has potential as a biological marker.