188530-60-1Relevant academic research and scientific papers
Chloroperoxidase-catalyzed amino alcohol oxidation: Substrate specificity and novel strategy for the synthesis of N-Cbz-3-aminopropanal
Masdeu, Gerard,Pérez-Trujillo, Míriam,López-Santín, Josep,álvaro, Gregorio
, p. 1204 - 1211 (2016)
The ability of chloroperoxidase (CPO) to catalyze amino alcohol oxidations was investigated. The oxidations of compounds with different configurations with respect to the amine position towards hydroxyl – using H2O2 and tert-butyl hydroperoxide (t-BuOOH) – were analyzed in terms of the initial reaction rate, substrate conversion, and CPO operational stability. It was observed that the further the amino group from the hydroxyl, the lower the initial reaction rate. The effect of the amino-protecting group and other substituents (i.e., methyl and hydroxyl) was also examined, revealing an increase in steric hindrance due to the effect of bulky substituents. The observed reaction rates were higher with t-BuOOH, whereas CPO was more stable with H2O2. Moreover, CPO stability had to be determined case by case as the enzyme activity was modulated by the substrate. The oxidation of N-Cbz-3-aminopropanol (Cbz, carboxybenzyl) to N-Cbz-3-aminopropanal was investigated. Main operational conditions such as the reaction medium, initial amino alcohol concentration, and peroxide nature were studied. The reaction kinetics was determined, and no substrate inhibition was observed. By-products from a chemical reaction between the formed amino aldehyde and the peroxide were identified, and a novel reaction mechanism was proposed. Finally, the biotransformation was achieved by reducing side reactions and identifying the key factors to be addressed to further optimize the product yield.
Large α-aminonitrilase activity screening of nitrilase superfamily members: Access to conversion and enantiospecificity by LC-MS
Bordier, Franck,Stam, Mark,Darii, Ekaterina,Tricot, Sabine,Fossey, Aurelie,Rohault, Johanna,Debard, Adrien,Mariage, Aline,Pellouin, Virginie,Petit, Jean-Louis,Perret, Alain,Vallenet, David,Salanoubat, Marcel,Weissenbach, Jean,Vergne-Vaxelaire, Carine,De Berardinis, Veronique,Zaparucha, Anne
, p. 79 - 88 (2014/07/08)
A high-throughput screening for the identification of nitrilases demonstrating activity towards alpha-aminonitriles is reported. A LC-MS assay giving access to both conversion and enantiospecificity was developed. 588 candidate enzymes were screened as cell lysates against six alpha-aminonitriles in 96-well microplates. The candidate enzymes were selected following two criteria, their sequence identity with a set of known nitrilases or their phylogenetic position among the nitrilase superfamily. Five enzymes were identified and found to hydrolyse alpha-aminonitrile into the corresponding alpha-aminoacid. The substrate range was found to be very narrow as only two different alpha-aminonitriles, 2-aminovaleronitrile and 2-amino-2- phenylacetonitrile, were found to be substrates. The biocatalytic capabilities of three enzymes were further investigated and the best result was obtained with an enzyme from Burkholderia xenovorans catalysing the enantiospecific hydrolysis of 2-aminovaleronitrile into (S)-norvaline with excellent conversion and enantiomeric excess.
Enantioselective synthesis of cryptopleurine and boehmeriasin A via organocatalytic intramolecular aza-Michael addition
Zeng, Chuanqi,Liu, Hanbin,Zhang, Mengyao,Guo, Jiajia,Jiang, Shunchao,Yu, Shouyun
supporting information, p. 2251 - 2254,4 (2020/07/31)
The enantioselective synthesis of phenanthroquinolizidine alkaloids cryptopleurine and boehmeriasin A was achieved in eight steps from commercial available Cbz-protected 2-piperidinone in 22% and 20% overall yield, respectively. The key steps of this route are intramolecular enantioselective aza-Michael addition, intramolecular aldol addition, and oxidative coupling.
Construction of Chiral 2-functionalized Piperidine via Enzymatic Resolution and Palladium-catalyzed N-Alkylation
Hirai, Yoshiro,Nagatsu, Mayumi
, p. 21 - 22 (2007/10/02)
The palladium-catalyzed cyclization of the optically active urethan , which was obtained by enzymatic resolution of the racemic alcohol (1), gave the piperidine 6.This reaction affords highly efficient intramolecular chirality transfer.Compound 6 was converted into (+)-coniine and 2-hydroxymethylpiperidine.
