- Preparation Method for Homocystein Thiolactone or Selenolactone
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The present invention provides an expensive reagent such as homocysteine thiolactone or selenolactone as the main intermediate of erdosteine, or an expensive reagent such as HI. More specifically, A) a homoserine lactone or N - protected homoserine is reacted with a thiocarboxylic acid metal salt or selenocarboxylic acid metal salt (RCOXM, X=S or Se). B) Step A) of producing homocysteine thiolactone or homocysteine sonoactone by deprotection of N - protected homocysteine thiolactone or N - protected homocysteine seleactone. The present invention relates to a method for producing homocysteine thiactone or homocysteine senolactone or a salt thereof by the following reaction scheme. [Reaction Scheme] Then, this time. X Is S or Se, R and R ' are independently alkyl or aryl which is C1 - C6, and M is Na or K.
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Paragraph 0070-0074
(2021/09/14)
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- Continuous production method DL-cysteine thiolactone hydrochloride (by machine translation)
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The method comprises the following steps DL - reacting, methionine as raw material :(1) with DL - sulfuric acid continuously into a liquid-liquid-phase micro-channel reactor to generate, high-cysteine hydrochloride 15-18mol/L containing DL - high-cysteine hydrochloride in a hydrochloric acid system through dehydration condensation to obtain, high cystine hydrochloride DL - in a continuous circulation reaction . high cystine, is obtained by carrying out a continuous circulation reaction to a cathode chamber, DL - of a plate-and-frame type electrolytic cell in a hydrochloric acid system through a continuous circulation reaction to complete DL - collection of cysteine hydrochloride in a hydrochloric acid system through dehydration and condensation reaction, so as to form DL - high-cysteine hydrochloride in the next step; DL - (1) ;(2). The. method comprises the following steps of: continuously circulating the cathode, solution, from, the liquid-phase micro-channel reactor; and carrying out a reduction reaction in a hydrochloric acid system through a liquid-liquid-phase micro-channel reactor. (by machine translation)
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Paragraph 0039-0063
(2020/04/22)
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- DL-homocysteine thiolactone hydrochloride and preparation method and applications thereof
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The invention belongs to the technical field of medicine, and specifically relates to DL-homocysteine thiolactone hydrochloride and a preparation method and applications thereof. The synthesis methodof DL-homocysteine thiolactone hydrochloride comprises following steps: taking 2-methyl-4-chlorobutyryl chloride as the raw material to prepare an intermediate; distilling the intermediate, collectingdistillate; mixing the distillate with iodine and ammonia water to carry out reactions; and finally re-crystallizing and purifying the reaction product to obtain DL-homocysteine thiolactone hydrochloride. According to the synthesis method, 2-methyl-4-chlorobutyryl chloride is taken as the raw material to prepare DL-homocysteine thiolactone hydrochloride; and the preparation method has the advantages of low cost, small environmental pressure, safe and convenient production, and high yield, and is suitable for large scale production.
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Paragraph 0021-0041; 0046
(2019/06/30)
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- Novel synthetic method of DL-homocysteinethiolactone hydrochloride
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The invention discloses a novel synthetic method of DL-homocysteinethiolactone hydrochloride. According to the novel synthetic method, DL-methionine and metallic sodium are subjected to reduction reaction, an obtained reduction product is subjected to desalting, and is subjected to condensation de-watering in the presence of dilute hydrochloric acid so as to obtain the DL-homocysteinethiolactone hydrochloride. DL-homocysteine is obtained via one-step synthesis from methionine, and DL-homocysteinethiolactone hydrochloride is obtained via condensation of DL-homocysteine under acid conditions, so that a re-reduction process of conversion of DL-methionine into DL-homocysteine in the prior art is avoided, reaction steps are reduced, harsh high temperature reaction conditions are avoided, release of hypertoxic gas and production of a large amount of high-salt waste water are reduced, three waste discharge is reduced, and a large amount of energy consumption is reduced; and in addition, the medium used in the novel synthetic method can be recycled, and cost is reduced. The novel synthetic method is capable of satisfying green and environment-friendly technology requirements; operation is simple; preparation is convenient; cost is low; and the novel synthetic method is suitable for industrialized large scale production.
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Paragraph 0018; 0019; 0020; 0021; 0022; 0023; 0024-0034
(2018/01/03)
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- Process for the resolution of homocysteine-thiolactone
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The present invention relates to a process for the preparation of enantiomerically pure homocysteine-γ-thiolactone comprising optical resolution of racemic homocysteine-γ-thiolactone (I) with a chiral organic acid wherein one isomer is recovered as diastereomeric salt with the organic acid and the other isomer remaining in the mother liquor is submitted to racemisation with a catalytic amount of an aromatic aldehyde and submitted again to optical resolution with the same chiral organic acid.
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Page/Page column 6
(2008/12/08)
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