The Synthesis Of Deuterated Ginkgo Flavonoid Aglycones And Its Application In Ambient Mass Spectrometry Quantitative Analysis

Ginkgo biloba extract?GBE?is the extract of dry ginkgo biloba,which include two main active ingredient,terpene lactone components and flavonoids compounds.Standardized GBE was brouhgt forward by a German chemist firstly,that the content of flavonoides is more than 24percent and lactone compounds 6 percent are orthonormal.They are used as quality control index of GBE,this is also current GBE quality control index at home and abroad pharmaceutical industry.Most of the ginkgo biloba flavonoids compounds exist in the form of glycosides,quercetin,kaempferol and isohamnetin are the main aglycones after the hydrolysis of flavonoids.hasler regarded the three aglycones as the quality control index of detecting and monitoring ginkgo flavones.Traditional quantitative method of flavonoids is high performance liquid chromatography?HPLC?,although there are the characteristics of high sensitivity and accurate quantitative in HPLC,the mobile phase need to consume large amounts of organic reagent,and pretreatment process is complex,time-consuming.HPLC is not applicable to the rapid quantitative analysis of a large number of the samples in consideration of economy and environmental protection.As a new mass spectrometry ionization technology,ambient ionization technique has not only rapid analysis?in 10 seconds?,high flux,simple pretreatment,but also accurate and reliable measuring results.The article will produced dueterated three kinds of aglycones,which are used as isotope internal standard,applied to atmospheric pressure paper spray mass spectrum?PS-MS?quantitative analysis.With the purpose of establishing a fast accurate quantitative method of total content of flavonoids in the GBE.The main content of this paper is as follows:The synthesis and characterization of dueterated quercetin:On the basis of hydrothermal synthesis method and the homogeneous reaction conditions.Catalysts,reaction temperature,reaction time and so on,which have an effect on the results of synthetic reaction,are optimized.Results show that the reaction temperature is 160?,1-butyl-3-methyl chloride imidazole?ionic liquid?for cosolvent,35%DCl for acid catalyst,D₂O for deuterium solvents,4h,getting the product of the main peak of306?d5?in the negative ion mode,and the original material accounted for the proportion of less than 1%;The produce of the main peak of 303?d2?is achieved in the condition of CH₃OD pure solvents,140?,4h.The synthesis and characterization of dueterated kaempferol and isohamnetin,On the basis of hydrothermal synthesis method and the homogeneous reaction conditions.The reaction temperature,time and other conditions are optimized in the synthesis of dueterated kaempferol,Results show that the product of the main peak of 289?d2?was achieved in positive ion mode when the reaction temperature is 160?,reaction time is 4h in CH₃OD pure solvent,and the main peak has good selectivity and the yield is 98%;Adding the ionic liquid and 35%DCl/D₂O to the product of kaempferol-d2 can gain the product of kaempferol-d4 in the condition of 170?and 4h.when reaction temperature is 140?,time is4h,Isorhamnetin-d2 was obtained after chemical reaction in CH₃OD pure solvent.?3?The d2 products of three kinds of aglycones regarded as internal standard substance apply to PS-MS quantitative analysis of GBE,compared with the traditional HPLC quantitative.Results show that ginkgo flavonoids content of HPLC is 29.80%,the PS-MS is 28.01%,quantitative result of PS-MS is close to HPLC.Result indicates that the PS-MS quantitative method is accurate.