Green Fluorescent Protein (GFP) Chromophore With BINOL-modified: Synthesis, Characterization And Properties

During the past 20 years, the green fluorescent protein (GFP) has become a focus of attention. As an important tool, GFP has been used widely in the life science. Natural or wild-type GPPs have many deficiencies, which limit their application and promotion, so some requirements need to be improved. An important method is to change the structure of the GFP chromophore with natural or non-natural amino acid, thus the photophysical and photochemical properties of the GFP would be changed and a lot of novel GFP mutants have been gained. These mutants have been widely applied in many aspects, for instance, plant cells mark, pH detection, ion recognition and so on.1,1’-binaphthyl-2,2’-diol was broadly used in chiral catalysis, but the report on the synthesis of the fluorescent probes taking it as a fluorophore is less common. It has some unique advantages while using BINOL as fluorophore:1. BINOL is a chiral compounds, the skeleton of the correspo-nding fluorescent probe molecules will has a chiral feature, which makes it can recognize some chiral small organic molecules potentially; 2. Its intrinsic rigid planar structure can enhance the fluorescence intensity and the fluorescence quantum yield of fluorescent molecular probes; 3. the two hydroxyl groups of BINOL can play potential role in the object-identification and the stability of molecular structure; 4. There is a certain angle between the two naphthalene ring, which provi-des a natural molecule cavity, then, it is possible to improve the selectivity and sensitivity of the fluorescent probe.According to the structural characteristics of the GFP chromophore and the advantages of naphthol structure, several new GFP chromophore variants with chiral naphthol molecule skeleton was synthesized and characterized, all of them possess both the advantages of the two compounds. Some single-crystals of these compounds were obtained in methylene chloride-ethanol solution, and were detected by X-ray diffraction.The compound 8 and 15, having same structure but different configuration, were selected to study their fluorescence properties in the recognition to metal ions. It found that both of them have a good fluorescence properties, and they can recognize Fe3+selectively in DMF/H2O(v/v= 5:5), the interference of other metal ions to 8 is much less than that of 15, that is, Cu2+ and Zn2+ ions have a little influence on the latter 15.