New Methodology Research Of Coumarin Synthesis Of Flavonoids

Objective:Natural products are secondary metabolites isolated from plants,animals and microorganisms.Their chemical structure and pharmacological activities are unique and diverse.Since the use of penicillin as a drug,natural products have gradually become an important component of drugs and new drug development.The main source.Natural products may be good lead compounds but some natural products are low in nature,which requires chemical synthesis.Flavonoids are widely found in nature.They have protective effects on cardiovascular and cerebrovascular diseases,anti-oxidation,dilation of blood vessels,and other pharmacological effects.The oral absorption of flavonoids is poor,the activity is not strong,and the target is not concentrated.Limit their clinical use.The traditional flavonoid synthesis method is a stepwise synthesis with poor convergence and low efficiency.The starting point of this project is to use the principle of convergence to design new methods to improve the synthesis efficiency of flavonoids,and to prepare a large number of structural analogs of flavonoids?mainly B-ring-changing analogues?in a short period of time to provide drug structure-activity.Relationship research use.Methods:This project is designed to splicing two parts into flavonoids.It is only necessary to synthesize the AC ring and the B ring separately,and then splicing the Bring onto the AC ring.In a short time,a large number of B-ring structurally modified compounds can be synthesized.figure 1).Greatly improved the synthesis efficiency.Results: This topic has tried 30 kinds of Halogenated hydrocarbon reagent,and there are 15 successful ones.1-iodo-4-methylbenzene,1-bromo-2-methylbenze ne,1-iodo-2-methoxybenzene,1-iodo-4-methoxybenzene,2-bromonaphthalene,6-bromoquinoline,5-bromo-1,2,3-trimethoxybenzene,2-bromo-6-methoxypyridine,?4-bromophenyl??methyl?sulfane,2-bromopyridine,1-bromo-3,5-bis?trifluoromethy l?benzene,4-bromo-1,1'-biphenyl,1-fluoro-4-iodobenzene,toluene,1-bromoada mantane?There are 15 failures,3-bromopyridine,1-bromoadamantane,1-iodo-2-methylbenzene,1,3-dibromo-5-methylbenzene,4-bromobenzenethiol,1-bromo-2-?trifluoromethyl?benzene,1-bromo-4-?trifluoromethyl?benzene,Anisole,8-brom oisoquinoline,1-chloro-4-iodobenzene,1,3,5-trifluorobenzene,1-bromo-2-chlorob enzene,4-bromophenylhydrazine,2-bromothiazole,benzyl bromide?conclusion:Sixteen target flavonoids were synthesized,and the chemical structures of the derivatives were determined by ¹H-NMR,¹³C-NMR,IR and ESI-MS.The new flavonoid synthesis method explored in this topic is simple and efficient,and has practical significance.