The Modification Of Tyrosine Based On The Synthesis Of Benzotriazole Structure And Its Photo-stability

With the development of industry, chlorofluorocarbon compounds were widelyused, which has caused the ozone layer of the earth to be thinner and even ozoneholes. The results allow the increase of ultraviolet radiation arriving the earth surface.The strong sunlight can cause globulin and collagen fiber lesions which cause cataract,skin cancer and other diseases, and the degradation of polymers, such as plastics,rubber and fibers. Scientists have been working not only in the mechanism of photochemical reaction of amino acids, protein and materials, but also in the photoprotection of amino acids, protein and materials.In this paper, the interaction of different amino acids with dye during the processof photodegradation were discussed under the condition of weak acid. The resultsshow that the photolysis rate of tyrosine and tryptophan are high and their solutionbecome yellow which demonstrate that the photodegradation of tyrosine is one of themain cause of silk photoyellowing. Tyrosine can promote the photolysis of tryptophan,tyrosine and tryptophan can also promote the photolysis of histidine, phenylalanineand dye.There are poor photo-stability of protein and peptide compounds, the purpose ofthe research is to synthesis benzotriazole structure based on the modification of theside group of tyrosine which can absorb UV. It enhances photo-stability of aminoacids and protein fibers by absorbing UV.The paper use the side of group of tyrosine coupled with ortho-nitroaniline,realized the coupled modification on the side of group of tyrosine and synthesisbenzotriazole structure by reducing action of TD. By means of UV spectra，IR, MS,and1HNMR, the structures of the corresponding products of coupled modification oftyrosine (coupled products)and benzotriazole modified tyrosine(reduzates) were provedcoincident with the expected structure. And the benzotriazole structure UV absorberhas been synthesised, realized with chemical modification of tyrosine based on the synthesis of benzotriazole structure.In this paper, the photodegradation of benzotriazole modified tyrosine wasstudied. Contrasting the photodegradation of tyrosine with benzotriazole modifiedtyrosine in solution of formic acid at pH4. It shows that the photolysis ofbenzotriazole modified tyrosine was lower than tyrosine, and its photo-stability wasenhanced obviously. Compared to commercial benzotriazole type UV absorberUV-FAST W, the photodegradation of benzotriazole modified tyrosine and preventiveeffect for amino acids and dye were studied in this paper. The photo-stability ofbenzotriazole modified tyrosinee and UV-FAST W is almost same at the initial phaseof irradiation, and their preventive effect for amino acids and dye is about the same.But the photo-stability of benzotriazole modified tyrosine and its preventive effect foramino acids and dye is inferior to UV-FAST W after longtime irradiation.