Efficient synthesis of pyrenylalanine

An efficient synthesis Of L-3-(1'-pyrenyl)alanine (Pya), a highly fluoresce nt amino acid, is described. The amino acid was obtained by the classical a symmetric hydrogenation of chiral 1-acetyl-3-pyrenemethylidene-6-methyl-pip erazine-2,5-dione. In the proposed improved procedure mild conditions of th e synthesis were applied and the final product - N-tert-butoxycarbonyl-pyre nylalanine - was obtained in good yield. Pyrenylalanine, due to its interes ting photophysical properties, can be applied as a fluorescent probe in num erous biochemical and conformational studies.