Separation And Purification Of Chenodeoxycholic Acid And Synthesis Of Its Derivatives

Now,Ursodeoxycholic acid(UDCA)and Chenodeoxycholic acid(CDCA)are the two mainly drugs for the treatment of gallstones.The traditional preparation technology of UDCA is separation and purification from bear bile,so make use of CDCA as raw materials to synthesis UDCA is more and more popular.The CDCA is also the main ingredient of other medicament preparation such as Ursodeoxycho-lic acid.This paper use the pig bile cream after extracting bilirubin as raw materials,the content of CDCA in this waste pig bile paste is only 40%.In addition,this waste pig bile have many different kinds of bile,and the structures and properties of these bile compounds are similar,which greatly raise the difficult to purify CDCA.Now Most of the paste is treated as waste,which not only costs money to dispose,but also is harmful to our home.This paper use the concentrated pig bile cream as raw materials to study the ways of purifying CDCA by two newly ways: the fir-st way is combing derivatization with recrystallization;the second way is Solvent recrystallization.The former uses 4-nitrobenzoyl chloride as derivatization reagent,trimethylamine as catalyst,form derivatization under room temperature by esterificati-on reaction.The ramification is purified by recrystallization.At last the ramification is hydrolyzed using sodium hydroxide,acquiring the pure CDCA.The latter uses sodium hydroxide saponifying 1.5 h,extracted with butyl acetate,washed three tim es with solution,concentrated under vacuum,recry-stallized with dichloromethane,acquiring the pure CDCA.It takes less than 10 hour-s,while the existing technolog y of purifying CDCA needs 20~30 h,our study req-uire less time to do acquiring the pure CDCA,avoiding to form calcium salt,mag-nesium salt,barium salt,ammo nium salt,which are toxic and harmful precipitation.This paper puts forward a kind of process to acquire the pure CDCA from pig bi-le cream after extracting biliru bin,which has great economic benefit and is able to industrialize.The method of high performance liquid chromatography-differential refractive in dex(HPLC-RID)analysis of CDCA is discussed in methodology reliability evaluatio n.In this paper,the analytical method is using methanol: acetonitrile: Water: Phosp horic acid =250:250:350:0.16(v/v/v/v)as mobile phase,RID as detector.Studying t he solution stability of CDCA in the mobile phase system.In order to evaluate this method,verify the reliability of the method.The results are that CDCA has superi or stability in the solution,that at solution concentration range from 21 mg/mL to3.5 mg/mL,the method has good linear relation,that the repeatability of method(pr ecision)and the recovery(accuracy)completely meet the needs for analyses.The derivatization experiment: using the esterification reaction between derivatiz-ation reagent and after being purifying the CDCA methyl ester.The derivatization reagents are 2-methyl-4-(trifluoromethyl)thiazole-5-carbonyl chloride,pivaloyl chlorid-e,nicotinoyl chloride,3,5-dimethylbenzoyl chloride,2,6-difluorobenzoyl chloride,2,4-dichlorobenzoyl chloride,4-bromo-3-fluorobenzoyl chloride.There are 7 esterifica-tion derivatives shown in the paper,they are characterized by mass spectrometry and NMR hydrogen spectra.The antibacterial experiment: seven kinds of the derivatives are tested for the antibacterial activity by filtering paper method,against Pseudomonas aeruginosa,Baci llus subtilis,Escherichia coli and Staphylococcus aureus,which provides fundamenta-l research data of the antibacterial activity of CDCA derivatives.