Acetoxymethyl-BODIPY dyes: a universal platform for the fluorescent labeling of nucleophiles

Current methods for the preparation of functional small-molecule fluorophores generally require labor-intensive, multi-step synthetic routes for all the major chromophoric groups. In spite of recent significant contributions from numerous laboratories, the paucity of rapid, straightforward and wide-scope synthetic strategies in this field is limiting the development of advanced probes for bioimaging, sensing and therapeutic applications. We describe herein a general and robust methodology for the one-step fluorescent labeling of a wide variety of molecules having C-, N-, P-, O-, S-, or halide-nucleophilic centers, using stable and readily available acetoxymethyl-BODIPYs as reagents in the presence of an acid catalyst. This modular methodology allows a very facile preparation of mono- and di-functional probes incorporating a broad assortment of biomolecules, enzyme cofactors, natural products, and other chromophores, as well as chemical functionalities for a wide range of applications including bioorthogonal conjugation, polymerization, and supramolecular chemistry, among others. The photophysical properties and preliminary applications of the new probes in live-cell imaging were also studied. The described strategy enables the high-throughput engineering of novel BODIPY dyes with diverse functionalities for basic and applied science with potential for innovative technological applications.