128573-54-6Relevant academic research and scientific papers
ENANTIOSELECTIVE REDUCTION OF β,χ-UNSATURATED α-kETO ACIDS USING BACILLUS STEAROTHERMOPHILUS LACTATE DEHYDROGENASE: A NEW ROUTE TO FUNCTIONALISED ALLYLIC ALCOHOLS
Casy, Guy,Lee, Thomas V.,Lovell, Helen
, p. 817 - 820 (1992)
The enantioselective reduction of α-keto acids, catalysed by lactate dehydrogenase, has been extended to β,χ-unsaturated substrates, providing functionalised allylic alcohols in high optical purity.
Synthesis of α-hydroxycarboxylic acids from various aldehydes and ketones by direct electrocarboxylation: A facile, efficient and atom economy protocol
Singh, Kishanpal,Sohal, Harvinder Singh,Singh, Baljit
, p. 839 - 845 (2021/04/09)
In present work, the formation of α-hydroxycarboxylic acids have been described from various aromatic aldehydes and ketones via direct electrocarboxylation method with 80-92% of yield without any side product and can be purified by simple recrystallization using sacrificial Mg anode and Pt cathode in an undivided cell, CO2at (1 atm) was continuously bubbled in the cell throughout the reaction using tetrapropylammonium chloride as a supporting electrolyte in acetonitrile. The synthesized compounds obtained in fair to excellent yield with a high level of purity. The characterization of electrocarboxylated compounds was done with spectroscopic techniques like IR, NMR (1H & 13C), mass and elemental analysis.
Method for preparing lisinopril intermediate
-
Paragraph 0047; 0049; 0050, (2017/04/03)
The invention provides a method for preparing a lisinopril intermediate. The lisinopril intermediate is (R)-2-hydroxyl-4-phenylbutyrate. The method has the advantages that the lisinopril intermediate is made of inexpensive and easily available raw materials which are benzaldehyde and pyruvic acid, four-step efficient reaction including condensation, biological enzyme catalytic asymmetric reduction, double-bond hydrogenation and esterification is carried out on the benzaldehyde and the pyruvic acid, and accordingly an optically pure target product (R)-HPBE [(R)-2-hydroxyl-4-phenylbutyrate] can be ultimately obtained at the overall yield of 83%.
Structure and absolute configuration of new acidic metabolites from Stachys ehrenbergii
Cincinelli, Raffaella,Scaglioni, Leonardo,Arnold, Nelly A.,Dallavalle, Sabrina
, p. 5972 - 5975 (2011/11/30)
Two novel metabolites have been isolated from the aerial parts of Stachys ehrenberiigii. Their structures and stereochemistry were elucidated using a combination of 13C and 1H homo and heteronuclear 2D NMR experiments and mass analysis. The development of an enantioselective synthesis of 3-(2′-acetoxy-4-phenylbut-3′-enoylamino)propionic acid allowed to confirm the structure and assign the (R) absolute configuration at C-2′ of the natural product.
Direct asymmetric hydrogenation of 2-oxo-4-arylbut-3-enoic acids
Zhu, Lvfeng,Meng, Qinghua,Fan, Weizheng,Xie, Xiaomin,Zhang, Zhaoguo
supporting information; experimental part, p. 6027 - 6030 (2010/11/18)
A challenging direct asymmetric hydrogenation of (E)-2-oxo-4-arylbut-3- enoic acids to give 2-hydroxy-4-arylbutanoic acids (85.4-91.8% ee) was achieved with a Ru catalyst based on SunPhos as the chiral ligand. Further investigation of the reaction revealed that partial isomerization of 2-hydroxy-4-arylbutenoic acids was involved in the hydrogenation process. Employing the reaction conditions to the hydrogenation of 2-oxo-4-phenylbutanoic acid resulted in better enantioselectivity (91.8% ee) and efficiency (TON = 2000, TOF = 200 h-1), which offers a useful method for the synthesis of a common intermediate for ACE inhibitors.
Lipase activity of Lecitase Ultra: characterization and applications in enantioselective reactions
Mishra, Mithilesh Kumar,Kumaraguru, Thenkrishnan,Sheelu, Gurrala,Fadnavis, Nitin W.
experimental part, p. 2854 - 2860 (2010/04/05)
The general properties of Lecitase Ultra, a phospholipase manufactured and marketed by Novozymes, Denmark, have been studied after purification by ultrafiltration. The enzyme has a molecular mass of 35 KD, pH-optimum of 8.5, and appears to possess a single active site which exhibits both the lipase and phospholipase activities that increase in the presence of Ca2+ and Mg2+ ions. The enzyme is inhibited by heavy metal ions and surfactants, and does not accept p-nitrophenyl acetate and glycerol triacetate. Substrates, such as glycerol tributyrate and p-nitrophenyl palmitate, esters of N-acetyl-α-amino acids and α-hydroxy acids are readily accepted. Amino acids with aliphatic residues, such as alanine, isoleucine, and methionine, are hydrolyzed with high enantioselectivity for the l-enantiomer (E >100), but amino acids with aromatic residues such as phenylalanine and phenylglycine, and esters of α-hydroxy acids are hydrolyzed with low enantioselectivity (E = 1-5). Immobilization of the enzyme in a gelatin matrix (gelozyme) leads to a marginal improvement in the enantioselectivity for these substrates. However, a dramatic improvement in enantioselectivity is observed for ethyl 2-hydroxy-4-oxo-4-phenylbutyrate (E value increases from 4.5 to 19.5 with S-selectivity). Similarly, glycidate esters, such as ethyl trans-(±)-3-phenyl glycidate and methyl trans-(±)-3-(4-methoxyphenyl) glycidate, are selectively hydrolyzed with a remarkable selectivity towards the (2S,3R)-enantiomer providing unreacted (2R,3S)-glycidate esters (ee >99%, conversion 52-55%) by the immobilized enzyme.
Decomposition of sodium trichloroacetate in the presence of quaternary ammonium under microwave irradiation: A convenient one-pot synthesis of α-hydroxy acids in water
Yu, Haitao,Fang, Yun,Xia, Yongmei,Wu, Jing
, p. 2421 - 2426 (2007/10/03)
A good yielding phase-transfer-catalyzed procedure for one-pot preparation of α-hydroxy acids from carbonyl compounds and sodium trichloroacetate by in situ addition and hydrolysis under microwave irradiation is described. Decomposition of sodium trichloroacetate is strongly accelerated by the presence of quaternary ammonium. The reaction can be conducted in water. Copyright Taylor & Francis Group, LLC.
The substrate spectrum of mandelate racemase: Minimum structural requirements for substrates and substrate model
Felfer, Ulfried,Goriup, Marian,Koegl, Marion F.,Wagner, Ulrike,Larissegger-Schnell, Barbara,Faber, Kurt,Kroutil, Wolfgang
, p. 951 - 961 (2007/10/03)
Mandelate racemase (EC 5.1.2.2) is one of the few biochemically well-characterized racemases. The remarkable stability of this cofactor-independent enzyme and its broad substrate tolerance make it an ideal candidate for the racemization of non-natural α-hydroxycarboxylic acids under physiological reaction conditions to be applied in deracemization protocols in connection with a kinetic resolution step. This review summarizes all aspects of mandelate racemase relevant for the application of this enzyme in preparative-scale biotransformations with special emphasis on its substrate tolerance. Collection and evaluation of substrate structure-activity data led to a set of general guidelines, which were used as basis for the construction of a general substrate model, which allows a quick estimation of the expected activity for a given substrate.
Chemo-enzymatic synthesis of (R)-and (S)-2-hydroxy-4-phenylbutanoic acid via enantio-complementary deracemization of (±)-2-hydroxy-4-phenyl-3- butenoic acid using a racemase-lipase two-enzyme system
Larissegger-Schnell, Barbara,Kroutil, Wolfgang,Faber, Kurt
, p. 1936 - 1938 (2007/10/03)
Deracemization of (±)-2-hydroxy-4-phenylbut-3-enoic acid was accomplished by lipase-catalyzed kinetic resolution coupled to mandelate racemase-mediated racemization of the non-reacting substrate enantiomer. Stepwise cyclic repetition of this sequence led
Synthesis of homochiral 2-hydroxy acids
-
, (2008/06/13)
A process for the production of a homochiral 2-hydroxy carboxylic acid or salt thereof corresponding to general formula (I), wherein R represents one of formulae (II), (III), (IV), (V), wherein R' represents straight- or branched-chain alkyl or phenyl opt
