Design, Synthesis And Properties Of Small Molecule Fluorescent Probes Based On Indole Analogs

The small molecular fluorescent probe has the advantages of high sensitivity,good selectivity,convenient operation and fast speed;Theresearch is of great significance in the fields of chemistry and biology,and it provides a good foundation for medical diagnosis and treatment.In this paper,three novel probes are designed and synthesized,one of them is a novel coumarin derivative compound 1,which is highly efficient and specifically recognizes cysteine;The other two probes,GMP-1 and GMP-2,were synthesized from benzimidazole and indolaldehyde as materials for the determination of guanosine 5-disodium monophosphate hydrate.A novelfluorescent probe compound 1for the detection of cys base on the excellent performance of coumarinwas designed and synthesized.The probe has high selectivity to the target molecule Cys at the test conditions of CH₃CN/HEPES?0.02 mol/L,pH=7.4?=1:9.It has been proved by experiment that the interaction between probe and target molecule is achieved by cysteine-induced SNAr substitution.After adding Cys,the fluorescence enhancement at 456 nm about 20 times can be observed,meanwhile,the color of the probe solution changs from purple visible to the naked eye to pink,and the fluorescence changs from almost no to green.Thecompound 1can be successfully applied for the fluorescence imaging of cysteine in Hi5 cell and C.elegans.Two new compoundsGMP-1 and GMP-2,were designed and synthesized based on benzimidazole and indolaldehyde.There probes have high selectivity sensitivityat pH7.4 in deionized water?DMSO-H₂O,8:2,v/v?about GMP-1 and in pure organic phase?H₂O with 1%?about GMP-2.Reaction mechanism is attributed to the combination through the hydrogen bonding.After adding GMP,the fluorescence increase and then decrease at 505 nm,and enhancement at 556 nm about 5-fold can be observed about GMP-1,and the fluorescence increase and then decrease at 500 nm,and enhancement at 550 nm about GMP-2.At the same time,the color of the probe solution changed from visible light green to orange-red,and the fluorescence color changed from green to kelly.GMP-1 exhibited better water-soluble and mitochondrial localization introduces Pph3 over GMP-2.In addition,GMP-1 and GMP-2can be successfully applied for the fluorescence imaging of GMP in Hi5 cell and C.elegans.