Design,Synthesis And Biological Evaluation Of Novel Neuroprotective Agents

Stroke includes ischemic stroke and hemorrhagic stroke based on different pathogenesis.The incidence of ischemic stroke is higher than that of hemorrhagic stroke,accounting for 75%?85%of the total stroke patients.So it is benefit to develop ischemic stroke new drugs for the economy and society.In recent years,neuroprotective agents,which have the advantages of reducing the area of cerebral infarction,no risk of bleeding,and no need for detailed diagnosis,have become a hotspot in the treatment of ischemic stroke.So it will make early prevention or treatment of stroke to be possible.In this paper,we use edaravone(a brain neuroprotective agent)and Fenazinel Hydrochloride(a first class of anti-stroke drug discovered by our research group)as the lead compound.Then use pharmacophore fusion principle to design,synthesize new compounds.To find new active molecules with better activity for neuroprotection.The research content is as follows:1 Design new compounds1)Taking Edaravone as lead compounds,series A new compounds were designed and synthesized by introducing natural products fragments with neuroprotective activities-ferulic acid and its derivatives.Using esters of hydroxy and carboxylic acids of edaravone carbonyl enols to form esters and enriching their structural types,14 novel derivatives of class A were designed and synthesized.2)Based on the activity results in vitro anti-ADP-induced platelet aggregation assays and glutamate-induced neuronal protection assay of class A compounds.SIPI8271 with the best comprehensive activity in vitro was selected as the lead compound,and the 2,3-dimethoxy substituted cinnamic acid fragment was retained on the left side.The edaravone moiety was replaced and modified,and 13 B compounds were designed and synthesized.3)Using Fenazinel as lead compound,while retaining the Fenazinel pharmacophore group,and combine amantadine that has a certain therapeutic effect on ischemic and hypoxic brain damage,or to combine both amantadine and Cinnamic acid derivatives,then design,synthesis of 12 compounds of class C.2 In vitro anti-ADP induced platelet aggregation activityIn vitro anti-ADP induced platelet aggregation activities of the compounds were evaluated by ADP-induced rat platelet aggregation model.The results are as follows:1)In series A,at the concentration of 100 ?M,seven compounds,SIPI7629,SIPI8268,SIPI8270,SIPI8271,SIPI8272,SIPI8274,and SIPI8357,inhibited ADP-induced rat platelet aggregation to a certain extent,among which the inhibitory activity of compound SIPI8271 was best,reach 50.36.2)In series B,at 100 ?M concentration,ferulic acid,edaravone,SIPI5052,SIPI8357,SIPI 8319,SIPI 8324,and SIPI 8330 had a certain degree of inhibition on platelet aggregation induced by ADP in rats,and the aggregation inhibition rate was 9.6.%?20.1%;The positive drug aspirin inhibited platelet aggregation in rats induced by ADP by 27.05%.All other test substances had no obvious inhibitory effect on platelet aggregation induced by ADP in rats.3 In vitro Anti-cerebral neuronal damage activityIn vitro neuroprotective activities of the compounds were evaluated by glutamate-induced neuronal SH-SY5Y injury model.The results are as follows:1)In series A,administration of glutamate(100 mM)significantly reduced neuronal cell viability,this effect could be reversed by the positive drugs Fenazinel hydrochloride,ferulic acid and synthetic edaravone.The 8271(10 ?M)of the test substance had a similar effect to that of Fenazinel hydrochloride.Other compounds showed no obvious anti-glutamate-induced excitotoxicity.2)In series B,SIPI 8320(10 ?M)has a similar effect to that of Fenazinel hydrochloride(88.7±1.1%);SIPI8325(50 ?M)and SIPI 8330(10 ?M)have an effect against glutamate-induced neuronal excitotoxicity injury.3)In series C,SIPI7184(10 ?M)and SIPI7191(10 ?M)had a similar effect(73.1±2.2%)as Fenazinel hydrochloride hydrochloride,suggesting that it has potential for further development.4 Result of hERG potassium ion inhibition testThe hERG potassium ion inhibition test of the compounds with in vitro activity showed that the IC50 values of the compounds SIPI8271,SIPI8330 and SIPI7184 were all above 40 ?M,indicating that the designed compound had a lower potential cardiac toxicity,suggesting that it has potential for further development and achieved the purpose of compound design..5 Synthesis of new compounds1)Synthesis of series A compound:Substituting benzaldehyde as a raw material to produce intermediate 1 through Knoevenagel condensation reaction.Intermediate 1 is condensed with edaravone and purified by column chromatography to obtain target series A compounds.2)Synthesis of series B compound:Ethyl acetophenone derivative is produced by reacting substituted phenylhydrazine hydrochloride with ethyl acetoacetate or ethyl trifluoroacetoacetate.2-3-dimethoxybenzaldehyde is used as a raw material to generate 2-3-dimethyl Oxycinnamic acid.2-3-dimethoxycinnamic acid is condensed with the corresponding edaravone derivative and purified by column chromatography to obtain the target series B compounds.3)Synthesis of series C compound:Four routes were used to synthesize C1 and C2 compounds in a total of 7 steps.The synthesis methods included condensation,nucleophilic substitution,nitrosation and reductive debenzylation.A total of 12 series C compounds were synthesized.A total of 39 target compounds were synthesized and their chemical structures were confirmed by MS and 1H-NMR.In summary,some of the new series of compounds designed in this paper retain the anti-ADP-induced platelet aggregation activity similar to that of the original lead compounds and protect the damaged brain cells,and their potential cardiotoxicity is low.Among them,compounds SIPI8271,SIPI8330,and SIPI7184 are superior to anti-ADP-induced platelet aggregation activity and protective activities of damaged brain cells in vitro,and hERG has low myocardial toxicity,which has in-depth research value.This study provides a reference for discovering new anti-stroke active compounds that are highly effective and low toxic.