Ionic Perylenetetracarboxdiimides: Highly Fluorescent and Water‐Soluble Dyes for Biolabeling

Dying to be seen: A series of water-soluble and highly fluorescent perylenetetracarboxdiimides (PDIs) have been synthesized in high yields by introducing charged groups into the bay region of PDI (see picture; C gray, H white, S yellow, O red). They can be used for staining living cells as they are nontoxic.