4509-09-5Relevant articles and documents
Synthesis of 2-Fluoroacetoacetic Acid and 4-Fluoro-3-hydroxybutyric Acid
Mattingly, Stephanie J.,Wuest, Frank,Schirrmacher, Ralf
supporting information, p. 2351 - 2358 (2019/05/24)
The butyric acid scaffold is the base structure of several human metabolites that serve diverse and prominent biochemical roles including as oxidative sources of cellular energy and as substrates for biosynthesis. Derivatization of metabolites through incorporation of fluorine often alters bioactivity and can facilitate detection and analysis by nuclear magnetic resonance or positron emission tomography depending upon the fluorine isotope employed. We describe the synthesis of two new fluorinated butyric acids (and three related esters) that are derivatives of the metabolites acetoacetic acid and 3-hydroxybutyric acid. 4-Fluoro-3-hydroxybutyric acid is prepared from epoxy ester precursors via ring opening by triethylamine trihydrofluoride. 2-Fluoroacetoacetic acid is prepared by electrophilic fluorination of an acid-labile β-keto ester. The gradual pH-dependent decarboxylation of 2-fluoroacetoacetic acid is investigated by 19 F NMR spectroscopy.
Biocatalytic cascade for the synthesis of enantiopure β-azidoalcohols and β-hydroxynitriles
Schrittwieser, Joerg H.,Lavandera, Ivan,Seisser, Birgit,Mautner, Barbara,Kroutil, Wolfgang
supporting information; experimental part, p. 2293 - 2298 (2009/08/17)
A three-step, two-enzyme, one-pot reaction sequence starting from prochiral a-chloroketones leading to enantiopure (3- azidoalcohols and (3-hydroxynitriles is described. Asymmetric bioreduction of a-chloroketones by hydrogen transfer catalysed by an alcohol dehydrogenase (ADH) established the stereogenic centre in the first step to furnish enantiopure chlorohydrin intermediates. Subsequent biocatalysed ring closure to the epoxide and nucleophilic ring opening with azide, N3-, or cyanide, CN-, both catalysed by a nonselective halohydrin dehalogenase (Hhe) proceeded with full retention of configuration to give enantiopure (-azidoalcohols and (3-hydroxynitriles, respectively. Both enantiomers of various optically pure (-azidoalcohols and (-hydroxynitriles were synthesised.
Sequential kinetic resolution catalyzed by halohydrin dehalogenase
Elenkov, Maja Majeric,Tang, Lixia,Hauer, Bernhard,Janssen, Dick B.
, p. 4227 - 4229 (2007/10/03)
(Chemical Equation Presented) A sequential kinetic resolution catalyzed by halohydrin dehalogenase was employed for the synthesis of two valuable enantiopure building blocks. Resolution of methyl 4-chloro-3-hydroxybutanoate methylester ((R,S)-2) with use of a Trp249Phe mutant of halohydrin dehalogenase yielded methyl 4-cyano-3-hydroxybutanoate methylester ((S)-4) with 96.8% ee (40% yield) and (S)-2 with 95.2% ee (41% yield). This reaction is carried out in aqueous solution under mild conditions and provides access to a useful statin side-chain building block.
KINETIC RESOLUTION OF RACEMIC β,γ-EPOXY ESTERS WITH PIG LIVER ESTERASE (PLE, E.C. 3.1.1.1.)
Mohr, Peter,Roesslein, Lukas,Tamm, Christoph
, p. 2513 - 2516 (2007/10/02)
The β,γ-epoxy esters (+/-)-2 to (+/-)-6 were synthetisized.The E-values of kinetic resolution of 2, 3, 4, and 6 with PLE and the absolute configuration of the products of the hydrolysis were determined by the conversion to known compounds.
3-Hydroxyglutarate and β,γ-Epoxy Esters as Substrates for Pig Liver Esterase (PLE) and α-Chymotrypsin
Mohr, Peter,Roesslein, Lukas,Tamm, Christoph
, p. 142 - 152 (2007/10/02)
The pH dependence of the α-chymotrypsin-catalyzed hydrolysis of dimethyl 3-hydroxyglutarate (3) has been studied.The e.e. was determined by HPLC analysis of diastereoisomeric camphanoic-acid derivatives.Kinetic resolution of the β,γ-epoxy esters 10 and 24 by pig liver esterase has been shown to provide an alternative access to chiral β-hydroxy esters and acids of high optical purity.By this latter method, the unnatural enantiomer of γ-amino-β-hydroxybutyric acid (GABOB) has been sinthesized.Finally, dimethyl meso-3,4-epoxyadipate (19) was hydrolyzed by pig liver esterase with almost 100 percent selectivity.