FLUORINATED PEPTIDES INCORPORATING A 4-FLUOROPROLINE RESIDUE AS POTENTIAL INHIBITORS OF HIV PROTEASE

N-Fmoc-4-fluoro-L-proline methyl ester was prepared as an attractive s ynthon for both solid and solution phase peptide synthesis. Its use fo r the synthesis of Fmoc-Phe-Pro(F)-OMe and Fmoc-Pro(F)-Val-Val-OMe is presented. Direct fluorination with DAST of a 4-hydroxy proline residu e incorporated into a peptide and elongation from the terminal amino g roup allowed preparation of the hexapeptide Boc-Ala-Ala-Phe-Pro(F)-Val -Val-OMe, analogous to the p17-p24 gag junction of structural HIV prot eins. None of the fluoropeptides in the paper displayed anti-protease or anti-HIV activity.