Facile Synthesis of Tetrafluorotyrosine and Its Application in pH Triggered Membrane Lysis.

“Smart” peptides that lyse membranes in response to biological stimuli are of considerable interest. Herein, we report a facile synthesis of l-tetrafluorotyrosine (l-f4Y) and its utilization as a pH sensing element. The synthetic route affords gram quantities of l-f4Y within two days. Incorporation of this unnatural amino acid into magainin 2 gives a peptide that turns on its membrane-lytic activity upon mild acidification. [ABSTRACT FROM AUTHOR]