Synthesis And Properties Study Of Novel Fluorescent Probes Based On Xanthenes And Naphthalimide

Xanthene dyes(rhodamine, fluorescein) are weakly fluorescent and colorless with a spiro ring form. When the spiro ring structure of Xanthene is opened, a strong fluorescence emission and a significant color change will be found. Because Naphthalimide dye molecules have a simple structure, good thermal stability, light stability, moderate emission wavelength and easy modification, etc. it is an ideal fluorescent carrier.Here, two Rhodamine B-based fluorescent probes(L1-L2), two fluorescein-based fluorescent probes(L3-L4), a naphthalimide-based fluorescent probe(L5) were designed and synthesized. Furthermore, we investigated the spectral properties and applications in cell imaging. The structures of target compounds(L1-L5) have been characterized and confirmed by 1H NMR, 13 C NMR and HRMS.Compounds L1 and L2 are probe for Fe3+, which can selectively recognize Fe3+ in methanol and water mixed system; compound L3 is probe for SO32-, compound L4 is probe for N2H4, compound L5 is probe for Cu2+. All compounds(L1-L5) were successfully applied to fluorescence imaging in living cells, demonstrating their potential applications in biological environment.