Asymmetric synthesis of l-carnitine from (R)-3-chloro-1,2-propanediol
摘要:
A practical chemical synthesis of L-carnitine (1) has been accomplished from (R)-3-chloro-1,2-propanediol ((R)-4), which is a main by-product originated from (R,R)-Salen Co(III) catalyzed hydrolytic kinetic resolution (HKR) of (+/-)-epichlorohydrin. (R)-4 was utilized as a chiral starting material to prepare the key intermediate cyclic sulfite ((R)-5). The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of bioactive compounds. (C) 2011 Yun Xu Yang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
The synthesis of enantiomers of 1-[3-(4-aryl-piperazin-1-yl)-2-hydroxy-propyl]-pyrrolidin-2-one derivatives is described. These enantiomers; were synthesized starting from (R)- or (S)-1-chloro-2,3-dihydroxypropane using relevant cyclic sulfates as chiral intermediates. The enantiomeric purities of the final compounds were in the range of 99.3-100.0%, as determined by high performance liquid chromatography. The final compounds were found to display moderate potency as ligands for alpha(1)-adrenoreceptors. (C) 2009 Elsevier Ltd. All rights reserved.
A molecular modelling explanation of the unexpected stereochemistry observed in the alkylation of oxazinone-derived glycine equivalents using 4-chloromethyl-1,3,2-dioxathiolane-2-oxide
The (R)- and (S)-enantiomers of 4-chloromethyl-1,3,2-dioxathiolane-2-oxide were used as 'epoxide-like' synthons in the asymmetric alkylation of the enantiomers of oxazinone-derived glycine equivalents. The configurations of the obtained spiro compounds were easily determined using 20 nuclear Overhauser effect nuclear magnetic resonance experiments. Additionally, the mechanisms of the reactions performed were explained using molecular modelling. The spiro derivatives obtained can also be modified and hydrolysed to their corresponding amino acids, which are derivatives of 1-aminocyclopropane-1 -carboxylic acids. (c) 2015 Elsevier Ltd. All rights reserved.
[EN] METHOD FOR THE PREPARATION OF SUBSTITUTED OXAZOLIDINONES<br/>[FR] PROCÉDÉ DE PRÉPARATION D'OXAZOLIDINONES SUBSTITUÉES
申请人:SANDOZ AG
公开号:WO2012140061A1
公开(公告)日:2012-10-18
The present invention relates to methods for the preparation of a compound having the formula (X). Individual reaction steps as welt as intermediates are additionally claimed.
本发明涉及一种制备具有化学式(X)的化合物的方法。此外,还要求单独的反应步骤以及中间体。
Asymmetric synthesis of l-carnitine from (R)-3-chloro-1,2-propanediol
作者:Xu Qin Li、Yun Xu Yang、Wei Li Wang、Bin Hu、Hui Min Xue、Tian Yi Zhang、Xue Tao Zhang
DOI:10.1016/j.cclet.2011.01.007
日期:2011.7
A practical chemical synthesis of L-carnitine (1) has been accomplished from (R)-3-chloro-1,2-propanediol ((R)-4), which is a main by-product originated from (R,R)-Salen Co(III) catalyzed hydrolytic kinetic resolution (HKR) of (+/-)-epichlorohydrin. (R)-4 was utilized as a chiral starting material to prepare the key intermediate cyclic sulfite ((R)-5). The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of bioactive compounds. (C) 2011 Yun Xu Yang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.