摘要:
The present invention relates to a method for obtaining optically pure amino acids, including optical resolution and optical conversion. The method of the present invention significantly shortens the time taken for optical transformation, and enables the repeated use of an organic solution containing a chiral selective receptor, to thereby obtain optically pure amino acids in a simple and remarkably efficient manner, and to enable the very economical mass production of optically pure amino acids.
摘要:
A novel process for racemization of (S)-3-carbamoylmethyl-5-methyl-hexanoic acid to 3-carbamoylmethyl-5-methyl-hexanoic acid racemate has been developed.
摘要:
The title compounds are obtained by racemic resolution of D, L-homoalanin-4-yl-(methyl)phosphinic acid by precipitating out one of the diastereomeric salts with chiral bases such as quinine or cinchonine. The yield of desired enantiomers can be increased by transformed racemic resolution, the diastereomeric salt being precipitated when the undesired enantiomer is racemised in the presence of (hetero)aromatic aldehydes. The racemisation method is also suitable for optically active amino acids having other structures.
摘要:
본 발명에 따르면, 살리실산알데히드, α-아미노산 및 구리이온으로 된 구리금속착물을 라세미화 촉매로서 함유하는 유기상 및 광학활성을 갖는 α-아미노산을 함유하는 염기성 수성상을 상전이촉매의 존재 하에 접촉시킴으로써, 광학활성을 갖는 α-아미노산을 라세미화시키는 방법이 제공된다. 본 발명에 따른 α-아미노산의 라세미화 방법은 반응조건이 온화하므로 α-아미노산의 분해가 적어 수율이 높고, 라세미화 촉매의 재활용이 가능하며, 라세미화된 α-아미노산의 분리 정제가 용이하고, 라세미화 방법을 대량으로 수행할 수 있어 경제적이다.
摘要:
본 발명은 광학적 분할 및 전환을 포함하여 광학적으로 순수한 아미노산을 얻는 방법에 관한 것이다. 본 발명의 방법은 광학변환 시간이 획기적으로 단축되고, 키랄 선택적 수용체를 포함하는 유기용액을 반복적으로 사용하는 것이 가능하므로, 광학적으로 순수한 아미노산을 간단한 방법에 의해 매우 효율적으로 얻을 수 있으며, 매우 경제적으로 대량 생산할 수 있다.
摘要:
The invention provides an industrially advantageous process for the preparation of antimicrobial drugs and industrially advantageous processes for the preparation of intermediates of antimicrobial drugs. Specifically, a process for preparing compounds (VI-a) according to the following reaction scheme; and intermediates therefor: (A)
摘要:
The invention provides an industrially advantageous process for the preparation of antimicrobial drugs and industrially advantageous processes for the preparation of intermediates of antimicrobial drugs. Specifically, a process for preparing compounds (VI-a) according to the following reaction scheme; and intermediates therefor: (A)
摘要:
Tilidine isomerization and crystallization process, comprising providing a reaction mixture comprising cis-tilidine, a dicarboxylic acid, water and an alcohol having 3 to 6 carbon atoms; maintaining the reaction mixture at a temperature T of from 80 °C to 150 °C at specific conditions of time and temperature; removing water from the reaction mixture and crystallizing a trans-tilidine dicarboxylic acid salt from the reaction mixture. The process allows for an efficient integration of isomerization and separation and yields trans-tilidine in a form that is essentially free of side products which are difficult to separate.
摘要:
Mixture of L- and D-enantiomers of methyl glycine diacetic acid (MGDA) or its respective mono-, di or trialkali metal or mono-, di- or triammonium salts, said mixture containing predominantly the respective L-isomer with an enantiomeric excess (ee) in the range of from 10 to 75 %.
摘要:
The present invention relates to an improved process for the preparation of Fesoterodine and pharmaceutically acceptable salts thereof. The present invention particularly relates to a process for the preparation of fesoterodine and pharmaceutically acceptable salts thereof which involves use and preparation of R(+) benzyl tolterodine and fumarate salt of R(+)-[4-benzyloxy-3-(3-diisopropylamino-1-phenylpropyl)-phenyl]-methanol.