- Method for synthesizing L -selenium - methylselenocysteine
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The invention provides a method for synthesizing L -selenium - methylselenocysteine, and relates to the reaction of a compound of formula II or a salt thereof with dimethyl diselenoate, and the method comprises MBH. 4 The method comprises the following steps: directly synthesizing L - selenium - methylselenocysteine through a one-pot reaction under the action of alkali or synthesizing L - selenium - methylselenocysteine, and hydrolyzing to obtain L - selenium - methylselenocysteine. The synthesis method has the advantages of simple reaction. The method has the advantages of convenient operation, high product yield, good quality, low cost and suitability for industrialization.
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Paragraph 0053; 0055
(2021/11/27)
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- Synthesis method of methyl 2-acetylamino-3-chloropropionate
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The invention discloses a synthesis method of methyl 2-acetylamino-3-chloropropionate. The method comprises the following steps: adding L-serine methyl ester hydrochloride into dichloromethane, dropwise adding thionyl chloride A, carrying out a sectional controlled-temperature reaction, then performing cooling to 20 DEG C, adding water for layering, and removing impurities by activated carbon so as to obtain an aqueous 3-chloro-L-alanine methyl ester hydrochloride solution; controlling the temperature of the aqueous 3-chloro-L-alanine methyl ester hydrochloride solution to be 15-25 DEG C, dropwise adding an aqueous sodium bicarbonate solution and acetic anhydride at the same time, and keeping the temperature for 1-4 h after drop-by-drop addition is completed; and carrying out extracting, concentrating, recrystallizing, centrifuging and drying to obtain the methyl 2-acetylamino-3-chloropropionate. The system is heated in a sectional controlled-temperature mode, so the method has the advantages of mild reaction conditions, high reaction yield, and few byproducts; and the aqueous 3-chloro-L-alanine methyl ester hydrochloride solution is directly used as a reaction raw material, so that the yield and the purity of the final product are improved.
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Paragraph 0042; 0045; 0049; 0052; 0055; 0058; 0061; 0064
(2020/01/12)
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- N-acetyl-β-chloro-L-alanine methyl ester preparation method
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The invention provides a method for preparing N-acetyl-beta-chlorine-L-alanine methyl ester. The method includes the steps that (a) serine serves as a starting material and is esterified through methanol or ethyl alcohol, (b) the esterified matter is chlorinated through sulfoxide chloride, (c) the chlorinated matter undergoes acylation, (d) the acylated matter is recrystallized, and accordingly the N-acetyl-beta-chlorine-L-alanine methyl ester is obtained. The method is high in reaction yield, by-products are few, reaction mother liquor is recycled and reused, distilled liquid obtained after acylation is acetic acid and acetic anhydride, and the liquid is recycled and reused after being purified. Accordingly, cost is low, tail gas generated in reactions is absorbed through strong-base solutions to form salt and then is separated and used, and accordingly environment protection is achieved.
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Paragraph 0046
(2016/10/17)
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- Production technology of cycloserine
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The invention belongs to the field of chemical synthesis, and particularly relates to a production technology of cycloserine. According to the synthesis technology, D-serine is used as a starting material, three reactions of esterification, chlorination and cyclization are performed, and the cycloserine is obtained. The technological process is simple, the yield is high, and the purity is high. During the esterification reaction, diethyl ether is replaced with ethyl acetate, no 8-hydroxyquinoline is added for crude product preparation after the cyclization reaction, and usage of reagent diethyl ether likely to produce toxicity and the dangerous product 8-hydroxyquinoline is avoided. Meanwhile, the synthesis route is short, the cost is low, and the obtained product is stable in yield and controllable in quality.
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Paragraph 0037; 0038; 0039; 0040; 0041
(2016/10/31)
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- Dual inhibition of human leukocyte elastase and lipid peroxidation: In vitro and in vivo activities of azabicyclo[2.2.2]octane and perhydroindole derivatives
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A series of potent and selective human leukocyte elastase (HLE) inhibitors of the Val-Pro-Val type has been developed. Initially, the central proline residue was replaced by nonnatural amino acids Phi ((2S,3aS,7aS)- perhydroindole-2-carboxylic acid) and A
- Portevin, Bernard,Lonchampt, Michel,Canet, Emmanuel,De Nanteuil, Guillaume
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p. 1906 - 1918
(2007/10/03)
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- A new approach to the synthesis of di- and tripeptides with unnatural amino acids using organozinc chemistry
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Di- and tripeptides which incorporate an iodoalanine unit at the C-terminus can be converted into the corresponding organozinc reagents upon treatment with activated zinc. These C-terminal di- and tripeptide organozinc reagents react with electrophiles either under palladium catalysis, or by prior transmetallation to a zinc/copper reagent, to give di- and tripeptides incorporating non-proteinogenic amino acids without loss of stereochemical purity.
- Dunn, Michael J.,Jackson, Richard F. W.
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p. 13905 - 13914
(2007/10/03)
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- Monomers with urea groups
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There is disclosed a family of new vinyl monomers capable of forming polymers by free radical polymerization. The vinyl monomer is of the formula STR1 wherein R1 and R2 are substituted or unsubstituted hydrocarbons, X is O, NH or NR3, and R3 is substituted or unsubstituted hydrocarbon. The intermediates in the synthesis of these monomers are new beta-chloroalanine ureas. The polymers are useful in film and fiber formation and display good toughness. These new vinyl monomers also form a cyclic monomer.
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- Vinyl monomers and derived liquid crystalline polymers
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There is disclosed a new vinyl monomer capable of forming polymeric vesicles, micelles, monolayers, and side-chain liquid crystalline polymers. The vinyl monomer is of the formula wherein R1 is substituted or unsubstituted long chain alkyl or aryl and R2 is a hydrogen atom, alkyl, or aryl. The side-chain liquid crystalline polymers can be formed by free radical polymerization or by anionic polymerizations techniques. The different reaction methods give polymers of different configuration; the anionic technique results in a polymer having a nitrogen atom in the backbone. The polymers are useful in film and fiber formation and display good toughness.
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