126534-42-7Relevant articles and documents
Chiral C2-boron-bis(oxazolines) in asymmetric catalysis - A theoretical study of the catalyzed enantioselective reduction of ketones promoted by catecholborane
Bandini, Marco,Bottoni, Andrea,Cozzi, Pier Giorgio,Miscione, Gian Pietro,Monari, Magda,Pierciaccante, Rossana,Umani-Ronchi, Achille
, p. 4596 - 4608 (2006)
C2-Symmetrical boron complexes, prepared by the reactions of 2,2′-methylenebis(oxazolines) (BOXs) with catecholborane (CATBH), can be used as catalysts (5-10 mol-%) in the enantioselective reduction of prochiral ketones (ee 72-86 %), giving the desired alcohols in satisfactory yields. We have theoretically investigated the mechanism of the reduction of chloroacetophenone at the DFT level and the computational results have provided a complete mechanistic picture, which explains the stereochemical outcome of the reaction. The B-BOXate complex binds both the reducing agent CATBH and the carbonyl compound, activating the former as a hydride donor and enhancing the electrophilicity of the latter. Moreover, the structure of two boron-BOX (BOXate) complexes has been confirmed by means of X-ray diffraction techniques. Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
Biocatalytic preparation of a key intermediate of antifungal drugs using an alcohol dehydrogenase with high organic tolerance
Yan, Jinrong,Wang, Xiaojing,Li, Fangling,Yang, Lei,Shi, Guixiang,Sun, Weihang,Shao, Lei,Huang, Junhai,Wu, Kai
supporting information, (2021/10/20)
In this study, an alcohol dehydrogenase derived from Lactobacillus kefir (LkADH) was engineered and a simple and practical bioreduction system was developed for the preparation of (R)-2-chloro-1-(2, 4-dichlorophenyl) ethanol ((R)-CDPO), a key intermediate for the synthesis of antifungal drugs. Through active pocket iterative saturation mutagenesis, mutant LkADH-D18 (Y190C/V196L/M206H/D150H) was obtained with high stereoselectivity (99% ee, R vs 87% ee, S) and increased activity (0.44 μmol·min?1·mg?1). LkADH-D18 demonstrated NAD(P)H regeneration capability using a high concentration of isopropanol (IPA) as a co-substrate. Using 40% IPA (v/v), 400 mM of (R)-CDPO (90.1 g·L-1) was obtained via complete substrate conversion using 40 mg·mL?1 LkADH-D18 wet cells. The biocatalytic process catalyzed at constant pH with the cheap co-solvent IPA contributed to improved isolated yield of (R)-CDPO (97%), lower reaction cost, and simpler downstream purification, indicating the potential utility of LkADH-D18 in future industrial applications.
Deep Eutectic Solvents as Media in Alcohol Dehydrogenase-Catalyzed Reductions of Halogenated Ketones
Ibn Majdoub Hassani, Fatima Zohra,Amzazi, Saaid,Kreit, Joseph,Lavandera, Iván
, p. 832 - 836 (2019/12/24)
The application of deep eutectic solvents (DESs) in biotechnological processes has gained an outstanding relevance, as they can be used as greener media to obtain higher productivities and selectivities. In the present contribution, an eutectic mixture composed of choline chloride (ChCl): glycerol (1 : 2 mol/mol) has been used as a reaction medium in combination with Tris?SO4 50 mM buffer pH 7.5, applied to the alcohol dehydrogenase (ADH)-catalyzed reduction of various carbonyl precursors of chiral halohydrins. These alcohols are key intermediates of biologically active compounds, and hence they are of industrial interest. In the presence of up to 50 % v/v of DES, these biotransformations were achieved up to 300–400 mM of the α-halogenated ketone substrate, getting access to the final compounds with excellent conversions (usually >90 %) and enantiomeric excess (ee >99 %). Among the different ADHs tested, two stereocomplementary enzymes (Lactobacillus brevis ADH and Rhodococcus ruber ADH) afforded the best results, so both alcohol enantiomers could be obtained in all the studied examples. Selected bioreductions were scaled up to 250 mg and 1 g, demonstrating the potential that DESs can offer as media in redox processes for substrates with low solubility in water.
