Design and Synthesis of Fluorescence-Labeled TAK779 Analogs as Chemical Probes

<i>N,N</i>-Dimethyl <i>N</i>-[4-[[[2-(4-methylphenyl)-6,7-dihydro-5<i>H</i>-benzocyclohepten-8-yl]carbonyl]amino]benzyl]tetra-hydro-2<i>H</i>-pyran-4-aminium chloride (TAK779) has a potent binding affinity for the chemokine receptor CCR5 and low cytotoxicity; however, their interaction remains unknown. We designed and synthesized four fluorescence-labeled TAK779 analogs as chemical probes. Although the binding properties of the fluorescence-labeled TAK779 analogs for CCR5 could not be determined, it was found that they penetrate the cell membranes and localize to the microtubes of HeLa cells.