Optimized Synthesis Of Ligustrazine Derivative 247 And Its Neuroprotective Activity

Background:For more than ten years,under the guidance of the TCM theory,our research group had studied numerous compound prescriptions,which is consist of Ligusticum wallichii.By synthesising of Ligustrazine and other components,our research group had obtained a large number of new compounds.By a lot of experiments(PC12 cell model,RSC96 cell model,MCAO animal model),our research group had selected derivative 247 with neuroprotective activity.(already applied for the national patent).Some research data show that the derivative 247 had high neuroprotective activity,low toxicity.It is worth doing further research and development work.This paper got the financial support from National Natural Science Foundation of China<Discovery of lead compounds,based on pair medicines of Rhizoma Chuanxiong>(No.81173519)and Innovation Team Project Foundation of Beijing University of Chinese Medicine named ' Lead Compounds Discovering and Developing Innovation Team Project Foundation'(No.2011-CXTD-15).Objective:To study the synthesis of derivative 247.to explore the neuroprotective mechanism of derivative 247.To study the druggability of derivative 247.Study method:the synthesis process of derivative 247:synthesis of new intermediate of ligustrazine(TMP-CL).And the synthetic yield was increased to 75%,which laid a solid foundation for the pilot synthesis of Ligustrazine derivatives.By using response surface methodology,we had optimized the best value of the parameters(1g p-coumaric acid):reaction temperature of 107 degrees Celsius,reaction time 125min,the molar ratio of 2.23.Average yield of derivatives 247=73.21%(RSD=4.62%).By Giemsa,DAPI,AO/EB staining experiment,We had verified that the derivative 247 can significantly reduce the oxidative damage of rat Schwann cells.By using two fluorescent probe(DHE and DCFH-D A),we had verified that the derivative 247 can significantly reduce excess superoxide anion and hydrogen peroxide,so that the level of active oxygen in the cell is in a low level of dynamic equilibrium.By using a variety of enzyme activity experiments,we had verified that the derivative 247 can significantly improve the activity of superoxide dismutase and glutathione reductase,enhance intracellular GSH/GSSG ratio,increasing anti effect to oxidative damage.The study of druggability of derivative 247:On normal liver cells(L02)and canine kidney epithelial(MDCK)model,the damage rate of derivative 247 was less than 5%.The maximum tolerance of mice was 3000mg/kg.The primary metabolism of liver homogenate was analyzed.The main metabolic pathway was the either break of the ester bond or break of the ether bond.It provides some reference gist for structural modification.Conclusion:we had standardized the synthesis methods of derivative 247.we had optimizied the synthesis technology of derivatives 247,which is conducive to the expansion of industrialization production;the antioxidant,alleviate the oxidative damage is an important mechanism of 2 derivative 247 to exert neuroprotective activity.derivative 247,low toxicity to normal cells,failure rate is low.Given the maximum tolerance dose of mice,no one died.It worth to do further research and to develop derivative 247 into innovative drugs with neuroprotective effect.