Synthesis of a Water-Soluble BODIPY for Targeting and Assessing the Function of Endoplasmic Reticulum.

We report here on a straightforward methodology to synthesize a new water-soluble fluorescent probe Tris-BODIPY-OH 1 that contains three pH-independent hydrophilic arms. This probe has been prepared by exploiting a synthetic strategy that includes as a key step the combination of a Cu-(I)-catalyzed azide-alkyne cycloaddition (CuAAC) and a Sonogashira cross-coupling in a sequential one-pot approach. Tris-BODIPY-OH 1 provides a significant advancement in the field by expanding the BODIPY toolbox with a biocompatible water-soluble probe, which can be used to specifically label and assess the function of the endoplasmic reticulum.