Diphenylamine end-capped 1,4-diketo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DPP) derivatives with large two-photon absorption cross-sections and strong two-photon excitation red fluorescence.

Novel donor-pi-bridge-acceptor-pi-bridge-donor (D-pi-A-pi-D)-type 1,4-diketo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DPP) derivatives with end-capping diphenylamine groups have been synthesized and shown to exhibit large two-photon absorption cross-sections over a wide range of wavelengths with strong two-photon excitation red fluorescence.