1.Determination of Puerarin in Jiangtang Pill by TLC
Yingai XU ; Yajun WANG ; Dihui LI
China Pharmacy 2001;12(5):299-300
OBJECTIVE: To develop a method of thin- layer chromatographic scanning to determine the content of puerarin in Jiangtang pill METHODS: Silica GF254 thin- layer was used, and the mobile phase consisted of chloroform- methanol- water(7∶ 2 5∶ 0 25) with the detection wave- length of 254nm and the control wave- length of 370nm RESULTS: The linear range of puerarin was 0 4~ 2 0μ g The mean recovery was 99 40% (n=5) with RSD of 1 37% CONCLUSION: This method is accurate, reliable and can be used for the determination of puerarin in Jiangtang pill
2.Determination of in vitro Percutaneous Rate and in vitro of Release of Compound Patch of Hyperosteogeny
Yingai XU ; Yanru GE ; Yajun WANG ; Ying JIN ; Fenglong LI ;
Chinese Traditional Patent Medicine 1992;0(04):-
Objective: To study the feasibility of percutaneous absorption of Compound Patch of Hyperosteogeny(CPH). Methods: The content of ferulic acid,an index composition in percutaneous receptor fluid and release receptor fluid were determined by HPLC.Results: The results of in vitro transdermal delivery experiment and in vitro release experiment showed that ferulic acid permeated at the constant speed of 0.2142?g?cm -2 ?h -1 in 24 hours and its release coincided with Higuchi Equation.Futhermore,the release rate was 14.53?g?cm -2 ?h -1/2 . Conclusion: CPH is a skeleton controlledtransdermal delivery system whose permeation speed is limited by skin.
3.Absorption kinetics of breviscapine in intestine of rats in situ
Yingai XU ; Guorong FAN ; Shen GAO ; Zhanying HONG
Chinese Traditional and Herbal Drugs 1994;0(07):-
Objective To investigate the intestinal absorption kinetics of breviscapine in rats.MethodsThe intestinal absorption in small intestine and colon of rats in situ was investigated using circular perfusion and HPLC methods.The in situ absorption of scutellarin in the small intestine was studied and the effects on the intestinal absorption were observed at the various concentrations and different pH values using the same methods.Results The results showed that there were significant differences in both absorptive percentage and absorption rate constant(ka)in the small intestine between the experimental groups of rats with and without bile duct being ligated.The absorption rate constants in small intestine and colon were(0.107 1?0.013 0)and(0.070 7?0.008 9)h-1,respectively.No saturation phenomenon occurred and ka was almost kept unchanged at different concentrations of breviscapine.The absorption of breviscapine was not influenced by pH values ranging from 6.0 to 7.4.Conclusion The results indicates that breviscapine is absorbed more in small intestine than in colon.The absorption of breviscapine complied with the passive diffusion mechanism and first order kinetics.In conclusion,these results suggest that breviscapine could be prepared in oral sustained-release dosage form.
4.In situ rat intestinal absorption of hawthorn leaves flavonoids
Yingai XU ; Guorong FAN ; Shen GAO ; Zhanying HONG
Chinese Traditional Patent Medicine 1992;0(12):-
0.05).But the P_ eff values were significantly increased in the presence of P-glycoportein(P-gp)inhibitor,verapamil or digoxin.CONCLUSION:Rhamnosylvitexin can be classified into high penetrating drug.Passive diffusion dominates the absorptive transport behavior of rhamnosylvitexin in HLF.There is not a preferential absorption zone in the intestine for rhamnosylvitexin.The absorption and secretion of rhamnosylvitexin in HLF are mediated by the efflux transport system,P-gp.
5.A new synthetic process of dapagliflozin
Li MA ; Menghan ZHANG ; Zhiwei XU ; Yingai SUN ; Jing ZHU ; Yingbo HUANG ; Dayong ZHANG
Journal of China Pharmaceutical University 2017;48(1):42-45
This paper describes a practical process for a SGLT2 inhibitor dapagliflozin. The target product was synthesized from 1-chloro-2-( 4-ethoxybenzyl)-4-iodobenzene and 2, 3, 4, 6-tetra-O-acetyl-alpha-D-glucopyranosyl bromide by iodine-magnesium exchange, and coupling and acetyl removing reactions with the total yield of 50%. This practical process highlights fewer reaction steps, less waste and mild reaction conditions.