| Recently, with the rapid progress of gene, protein and enzyme technology, and with the modcrnize of separation and analysis, discovery of new bio-activity peptidcs is greatly promoted. Research and development of bio-activity or pharmaceutical peptides, including synthesis of precursor peptides, have become one of important aspects of international high and new technic fields.Peptides are traditionally synthesized in liquid phase, such methods are DCC, mixed anhydrides, acyl chloride and azide etc., which provide more choices for peptides synthesis. After that, on the foundermation of peplide synthesis in liquid phase, synthesis of peptide on the solid phase has been developed. Furthermore, in recent 30 years, enzymatic pcplidc synthesis has been the focus on pcptidc synthesis. With the progress of non-aqueous enzymatic study, more attention has been focused on the using of enzyme in organic synthesis. As compared to the chemical methods, enzymatic synthesis of peptide has many advantages. Some oligopeptide or their precursors such as APM, RGD have been synthesized by protein enzyme in non-aqueors medium in recent years,. Finally, some peptides can be prepared in large scale by using enzymatic reactor.RGD is composed of three amino acids, arginine(Arg), glycine(Gly) and aspartic acid(Asp). It is one of the oligopeptide sequence possessing bio-activity which has been found in recent years. RGD was proved to be a recognition site for celluar adhesion, spreading and motility of cells. As the competitive, reversible inhibitors for fib binding, RGD was used to study adhesive interaction between cells or adhesive interaction between cell and extra cellular matrix targeting the treatment of some diseases related to cellular adhesion such as tumor metastasis, thrombosis and acute renal failure. Generally, more and more attentions have been focused on the synthesis of RGD for it's latent great market value.We studied the radimentai synthesis technology and scheme, and investigated the mechanism of coupling reagent, anhydrides agent in the liquid synthesis of GD, RGD. At the same time, we researched the degree of differ factors which in infused the synthesis of peptides, accumulated correlative data, provided necessary technique parameters for large production of RGD.We used the DCC and anhydrides methods respectively to synthesis the HCl-Gly-Asp(oBzl)2 dipeptide and Z-Arg(Tos)-Gly-Asp(oBzl)2 tripeptide. The Gly-Asp(NH2)2 dipeptide was synthesised by acyl chloride method. The influence factors of synthesis reaction such as reaction time, solvent, ratio of substrates and theamount of base were investigated and the theory principle and technique data for thepreparation of RGD tripcptide in large scale were provided.In this study, we managed to enzymatic synthesis Z-Arg(Tos)-Gly-Asp(oBzl)2 andZ-Arg(Tos)-Gly-Asp(NH2)2 tripeptide by porcine pancrease lipase(PPL) and trypsin.And we discussed the synthesis mechanism and influence factors, especially focusedon the reaction time, solvent and water amount. Because of the limitation of time andlabortary instruments, this research haven't achieved the desired results, theadvantages of enzymatic synthesis pepticle have not brought into play. So it will beour major work in the future.In this paper, we analysed the experiment results and gave reasonable explanation, asa result we got some conclusion for guidance.(1) In the course of chemical synthesis of RGD, and for the consideration of that low dielectric constant solvent is useful for reducing byproducts and the high boiling point of DMF, which is very difficult for separation, so we substituded THF as solvent for DMF.(2) Mixed anhydrides synthesis GD dipeptides, to benefit the formation of complexes, tertiary amine, which contains at least one methyl, is a good choice.(3) DCC and mixed anhydrides methods all get the precursors BocGly-Asp(oBzl)2. To remove the Boc-group, HCl/EtAc and TFA can be used. However only by using HCl/EtAc, crystallination of HCl'Gly-As...
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