Synthesis of L-2,3,5,6-Tetrafluoro-4-(phosphonomethyl)phenylalanine, a Novel Non-Hydrolyzable Phosphotyrosine Mimetic and L-4-( Phosphonodifluoromethyl)phenylalanine

Abstract A new non-hydrolyzable phosphotyrosine analogue, L-F4Pmp and its N-Fmoc protected derivative were prepared by using an enantioselective synthetic pathway with camphor sultam as chiral auxiliary. The side chain pKa2 (6.9) of L-F4Pmp was determined. A new synthesis of L-F2Pmp was also described.