Enzymatic Synthesis of [1-¹³C]- and [1-¹⁴C]-L-Phenyl-Alanine

Abstract

Abstract The two isotopomers of L-phenylalanine labelled with 13C or 14C in the carboxylic group have been obtained by the combined chemical and enzymatic methods. [1–13C]- or [1–14C]-L-phenylalanine have been synthesised by conversion of [1–13C]- or [1–14C]CH3COONa into proper cinnamic acid species followed by ammonia addition in the presence of phenylalanine ammonia lyase. The reaction yield has been determined enzymatically and spectroscopically; radiochemical yield of 14C-compound has been determined by liquid scintillation counting, and the 13C enrichment level has been established by 13C NMR and mass spectroscopy methods.