Synthesis, Optical Properties, Preliminary Antimycobacterial Evaluation and Docking Studies of Trifluoroacetylated 3-Pyrrolyl Boron-Dipyrromethene

The article provides the route to trifluoroacetylated fluorescent boron dipyrromethene dye (2). The compound performs intensive absorption and emission bands in near-red wavelength region. Photophysical properties of 2 are investigated in different solvents. A notable increase of fluorescence quantum yield after trifluoroacetyl group insertion connected with a change in intramolecular interactions parameters. The role of molecular geometry aspects in observed photophysical properties and molecular fragments rotation energy barriers are explained by quantum-mechanical calculations. 2 performs considerable antimycobacterial activity. According to molecular docking simulations, 2 is capable of affinity binding in the active sites of mycobacterial MycP1 and MycP3 serine proteases. The geometries of final ligand-protein complexes show the possibility of protein active site covalent modification at the serine residue of the catalytic triad. At lower concentrations, 2 can act as a fluorescent dye for microscopy analysis and corresponding staining patterns are shown for Mycobacterium smegmatis and Staphylococcus aureus cells.