Several Nitrogen Compounds Interact With Two Proteins

As we all know,many drug molecules containing nitrides with antiviral and antitumor effects,meanwhile most of them may cause structural changes in proteins.Therefore,the interaction between nitrogen-containing compounds and proteins has become a topic of interest to researchers.In recent years,many scholars focus on this field.However,there are still some problems in this field:(1)Coenzymes are currently expensive,and the biosynthesis conditions are harsh,and there areless cheap and feasible preparation methods;(2)There are relatively few studies on the interaction between synthetic coenzymes,proteins and physiological activity.The mechanism research is not sufficient;(3)Alkaloids have antioxidant properties,superoxide dismutase has antioxidant properties,but the two have many adverse effects when used alone,and further research is needed to reduce their physiological toxicity.To solve the problems associated with coenzymes,xylose and glucose,which are also monosaccharides,they are used to synthesize coenzyme analogs.Through experimental exploration,we find the best conditions for the synthesis of nicotinamide derivatives.Based on the previous research,the research contents are as follows:1.First,we optimized the conditions of bromopyranose's synthesis it is found that for the synthesis process of the intermediate,the optimal temperature is 20 ?.Then the intermediate Glycosylation with nicotinamide.The molar ratio of the glycosylated bromopyranose of nicotinamide to nicotinamide is 2:1with a temperature range of 40-60?;finally,the deprotection is carried out.The methanol solution of ammonia is used in the deprotection process at-3? for 16 hours,the yield is 45%,which effectively reduces the production cost of coenzyme.2.Ultraviolet and fluorescence analysis techniques were used to study therelationship between nicotinamide derivatives and human serum albumin.The formation of a complex between nicotinamide derivatives and human serum albumin caused the fluorescence quenching of HSA.The number n of binding sites and the binding constant Ka,corresponding thermodynamic parameters,free energy change(?G),enthalpy change(?H)and entropy change(?S)at different temperatures were calculated by program,the calculation results showed van der Waals force and hydrogen bonding play a major role in stabilizing the complex,And the nicotinamide derivatives have statically quenched the HSA conformation.3.In view of the large physiological side effects of single use of alkaloids or superoxide dismutase(SOD).To study the antioxidant effect of TP,TB and CF along with activity of copper and zinc superoxide dismutase on TP,TB and CF.The content of MDA in cells showed that TP,TB and CF all have antioxidant activity,and close to the antioxidant effect of SOD(13.77 ?mol/g).By forming TP-SOD,TB-SOD,and CF-SOD,the antioxidant capacity can be superimposed.Through ultraviolet spectroscopy,fluorescence spectroscopy and molecular docking techniques,the interactiong between TP/TB/CF and SOD was studied,and it was found that hydrogen bonding and van der Waals forces stabilized the 1:1 complex of TP/TB/CF and SOD;The microenvironment and structure of SOD have changed.The above results indicate that the composite formation of TP-SOD,TB-SOD and CF-SOD can maintain their respective antioxidant effects,while the SOD activity has not changed.We explored the synthesis method of coenzyme analogs,and coenzyme analogs produce static quenching of human serum albumin;at the same time,it was found that the formation of alkaloids and SOD complex can play a synergistic role.