Abstract: In this paper, the existing literature on the basis of a brief description of the antiepileptic drug therapy, with a focus on antiepileptic drug (S) -2 - ethyl -2 - O -1 - pyrrolidine acetamide Technology. Screening for 2 - bromo-butyric acid as the starting material, after ammonolysis, esterification, ester amine solution, split, five-step cyclization reaction Levetiracetam. Methods used in esterification HCL / methanol and dichloro-sulfoxide and sulfuric acid to carry out experimental research aminate methanol saturated amines were used, plus salt, add water, three options to conduct experiments. Resolution of the use of non-resolution of enantiomers methods used in organic solvents tartaric acid for the separation agent, to be S-type. At the same time, this paper also split the R-isomer of racemic to change and re-recovery. Another direct use of this experiment (S )-(+)- 2 - tartaric acid amide ammonium salt hybroxybutyric cyclization experiments skip the first preparation of (S )-(+)- 2 - ammonia hybroxybutyric amide hydrochloride, and then related Preparation of Levetiracetam ring step. The synthetic route for the 25% overall yield. The process line is simple, low cost, high yield, large-scale production can be industrialized.
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green salt plus magnesium blend 四氟化铀与镁的混合物
Objective To observe the therapeutic effect of acupuncture plus salt partitioned moxibustion at Shenque (CV 8) on chloasma.
目的：观察针刺加神阙隔盐灸治疗黄褐斑的临床疗效。
Conclusion Acupuncture plus salt partitioned moxibustion at Shenque (CV 8) is a safe and convenient therapy with a remarkable effect for chloasma.
结论：针刺加神阙隔盐灸对黄褐斑是一种安全有效的治疗方法。
When you buy a pre-made sandwich, you're really just paying for its elaborate packaging — plus a whole lot of salt, fat, and unnecessary additives.
当您买回一个成品三明治， 您只不过是买了一个精致的包装—外加上很多盐、油脂和多余的添加剂。
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