7631-42-7Relevant articles and documents
Design and evolution of an enzyme with a non-canonical organocatalytic mechanism
Burke, Ashleigh J.,Lovelock, Sarah L.,Frese, Amina,Crawshaw, Rebecca,Ortmayer, Mary,Dunstan, Mark,Levy, Colin,Green, Anthony P.
, p. 219 - 223 (2019/10/21)
The combination of computational design and laboratory evolution is a powerful and potentially versatile strategy for the development of enzymes with new functions1–4. However, the limited functionality presented by the genetic code restricts t
Preliminary characterization of four 2-chlorobenzoate-degrading anaerobic bacterial consortia
Genthner, Barbara R. Sharak
, p. 27 - 34 (2007/10/03)
Dechlorination was the initial step of 2CB biodegradation in four 2-chlorobenzoate-degrading methanogenic consortia. Selected characteristics of ortho reductive dehalogenation were examined in consortia developed from the highest actively dechlorinating dilutions of the original 2CB consortia, designated consortia M34-9, P20-9, P21-9 and M50-7. In addition to 2-chlorobenzoate, all four dilution consortia dehalogenated 4 of 32 additional halogenated aromatic substrates tested, including 2-bromobenzoate; 2,6-dichlorobenzoate; 2,4-dichlorobenzoate; and 2-chloro-5-hydroxybenzoate. Dehalogenation occurred exclusively at the ortho position. Both ortho chlorines were removed from 2,6-dichlorobenzoate. Benzoate was detected from 2-bromobenzoate and 2,6-dichlorobenzoate. 4-Chlorobenzoate and 3-hydroxybenzoate were formed from 2,4-dichlorobenzoate and 2-chloro-5-hydroxybenzoate, respectively. Only benzoate was further degraded. Slightly altering the structure of the parent "benzoate molecule" resulted in observing reductive biotransformations other than dehalogenation. 2-Chlorobenzaldehyde was reduced to 2-chlorobenzyl alcohol by all four consortia. 2-chloroanisole was O-demethoxylated by three of the four consortia forming 2-chlorophenol. GC-MS analysis indicated reduction of the double bond in the propenoic side chain of 2-chlorocinnamate forming 2-chlorohydrocinnamate. None of the reduction products was dechlorinated. The following were not dehalogenated: 3- and 4-bromobenzoate; 3- and 4-chlorobenzoate; 2-, 3-, and 4-fluorobenzoate; 2-, 3-, and 4-iodobenzoate; 2-, 3-, and 4-chlorophenol; 2-chloroaniline; 2-chloro-5-methylbenzoate; 2,3-dichlorobenzoate; 2,5-dichlorobenzoate; 2,4,5-trichlorophenoxyacetic acid; and 2,4-dichlorophenoxyacetic acid. Consortia M34-9, P20-9, P21-9, and M50-7 dechlorinated 2-chlorobenzoate at -9 followed by those of M50-7 with rates declining above 2 and 3 mm 2CB, respectively. The major physiological types of microorganisms in consortia M34-9, P20-9, P21-9, and M50-7 were sulfate-reducing and hydrogen-utilizing anaerobes.
Degenerate transesteriflcation of dimeric lithium 2,4,6-trimethylphenolate and a further observation on the reaction of tetramers
Jackman, Lloyd M.,Chen, Xian
, p. 8681 - 8684 (2007/10/03)
The rates of exchange of the 2,4,6-trimethylphenolate ion between dimeric lithium 2,4,6-trimethylphenolate-d9 and a series of 2,4,6-trimethylphenyl esters [2,4,6-(CH3)3C6H2COOCH2R; R = CHs
Structure-Activity Relationships in the Esterase-catalysed Hydrolysis and Transesterification of Esters and Lactones
Barton, Patrick,Laws, Andrew P.,Page, Michael I.
, p. 2021 - 2030 (2007/10/02)
The Broensted exponents for the alkaline hydrolysis of alkyl esters are 1.3 and 0.4 for substitution in the acyl and alcohol portions, respectively, which is indicative of a transition state which resembles the anionic tetrahedral intermediate with a localised negative charge.By contrast, the rate of the pig liver esterase (PLE)-catalysed hydrolysis shows little dependence upon the electron-withdrawing power of substituents.The values of kcat are independent of the pKa of the leaving group alcohol suggesting rate-limiting deacylation.There is a small steric effect of α-substitution in both the alcohol and carboxylic acid residues for the enzyme-catalysed reactions but the enzyme rate enhancement factor remains high for most esters.There is no substantial ee observed for the hydrolysis of racemic esters although the kinetic data can be used for determining the regioselective hydrolysis of diesters.Unsubstituted lactones are poor substrates for PLE but derivatives with hydrophobic substituents show kcat/Km values similar to those for acyclic esters.Dihydrocoumarin undergoes transesterification catalysed by PLE, kcat increases with increasing alcohol concentration indicative of rate-limiting deacylation.There is enantioselectivity in the PLE-catalysed hydrolysis of some racemic lactones but little or none in the transesterification of racemic alcohols with dihydrocoumarin.
Electrochemical Reduction of Carbon Dioxide Using Iron-Sulfur Clusters as Catalyst Precursors
Nakazawa, Makoto,Mizobe, Yasushi,Matsumoto, Yoichi,Uchida, Yasuzo,Tezuka, Meguru,Hidai, Masanobu
, p. 809 - 814 (2007/10/02)
The potential-current relationships of DMF solutions of a series of iron-sulfur compounds have revealed that in the presence of clusters 2- (R=PhCH2 or But) and 3- (M=Mo or W) the electroreduction of CO2 proceeds at the potential shifted by about 0.7 and 0.5 V, respectively, to the positive direction compared to the potential at which CO2 is reduced without any catalyst.When controlled potential electrolysis of a DMF solution containing 2- was carried out under CO2 at -2.0 V vs.SCE, phenylacetate and formate were formed as the products resulting from CO2 reduction.The cubane structure of this cluster collapsed rapidly under these conditions.However, when excess amount of PhCH2SH was added to the catholyte, the cluster structure was preserved during a relatively long period of electrolysis, and the yield of phenylacetate increased but that of formate decreased compared with the reaction in the absence of free PhCH2SH.
