Novel triphenylamine-cored two-photon absorbing dyes for labeling of biomolecules

► Two novel triphenylamine-cored chromophores were synthesized. ► These two dyes have sizable two-photon absorption cross-section at 800 nm. ► They possess reasonable water solubility and are suitable as labels in aqueous biological environments. ► These dyes have strong chelating ability. ► They display a large set of reactivity for coupling to biomolecules.