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ChemicalBook CAS DataBase List Levetiracetam
102767-28-2

Levetiracetam synthesis

11synthesis methods
Levetiracetam is a derivative of Piracetam, suitable for adjuvant treatment of partial or secondary generalized seizures in adult epilepsy patients. Its synthesis method is as follows: Add anhydrous sodium sulfate to (S)-2-aminobutanamide hydrochloride in dichloromethane at room temperature, cool to 0°C, then add tetrabutylammonium bromide, stir for 30 minutes, add potassium hydroxide powder . 4-Chlorobutyryl chloride was added dropwise at 0°C with vigorous stirring. After the dropping was completed, potassium hydroxide powder was added after the reaction for 5 hours. After 2 hours, it was directly filtered, the filtrate was directly concentrated, ethyl acetate was added to the residue and refluxed for 30 minutes, and then  concentrationed to give the crude levetiracetam.
358629-51-3 Synthesis
(S)2-(2-Oxo pyrrolidin-1-yl)-Butiric acid methyl ester

358629-51-3
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Yield:102767-28-2 97.5%

Reaction Conditions:

with ammonium hydroxide at -5 - 0; for 8 h;

Steps:

1.D; 2.D; 3.D; 4.D D: Ammonolysis reaction

add ammonium hydroxide 60.81kg in the reactor, be cooled to -5degC , drip (S)-2-(2-oxopyrrolidin-1-yl) methyl butyrate 13.79kg, After dripping, the reaction was incubated at -50°C for 8 hours, the water was evaporated under reduced pressure, 62.5 kg of ethyl acetate was added to make pulp, centrifuged, and dried under reduced pressure to obtain 12.36 kg of the final product levetiracetam, with a molar yield of 97.5%. Starting from the starting material (S)-2-aminobutyric acid to the final product levetiracetam, the total molar yield was 48.28%, the HPLC purity was 99.90%, and the optical purity was 99.91%.

References:

CN114409586,2022,A Location in patent:Paragraph 0038; 0042-0043; 0047-0048; 0052-0053; 0057

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