709-08-0Relevant articles and documents
Discovery, Biocatalytic Exploration and Structural Analysis of a 4-Ethylphenol Oxidase from Gulosibacter chungangensis
Alvigini, Laura,Fraaije, Marco W.,Gran-Scheuch, Alejandro,Guo, Yiming,Mattevi, Andrea,Saifuddin, Mohammad,Trajkovic, Milos
, p. 3225 - 3233 (2021/10/04)
The vanillyl-alcohol oxidase (VAO) family is a rich source of biocatalysts for the oxidative bioconversion of phenolic compounds. Through genome mining and sequence comparisons, we found that several family members lack a generally conserved catalytic aspartate. This finding led us to study a VAO-homolog featuring a glutamate residue in place of the common aspartate. This 4-ethylphenol oxidase from Gulosibacter chungangensis (Gc4EO) shares 42 % sequence identity with VAO from Penicillium simplicissimum, contains the same 8α-N3-histidyl-bound FAD and uses oxygen as electron acceptor. However, Gc4EO features a distinct substrate scope and product specificity as it is primarily effective in the dehydrogenation of para-substituted phenols with little generation of hydroxylated products. The three-dimensional structure shows that the characteristic glutamate side chain creates a closely packed environment that may limit water accessibility and thereby protect from hydroxylation. With its high thermal stability, well defined structural properties and high expression yields, Gc4EO may become a catalyst of choice for the specific dehydrogenation of phenolic compounds bearing small substituents.
A xylenol orange-based screening assay for the substrate specificity of flavin-dependent para-phenol oxidases
Ewing, Tom A.,Van Noord, Aster,Paul, Caroline E.,Van Berkel, Willem J. H.
, (2018/01/18)
Vanillyl alcohol oxidase (VAO) and eugenol oxidase (EUGO) are flavin-dependent enzymes that catalyse the oxidation of para-substituted phenols. This makes them potentially interesting biocatalysts for the conversion of lignin-derived aromatic monomers to value-added compounds. To facilitate their biocatalytic exploitation, it is important to develop methods by which variants of the enzymes can be rapidly screened for increased activity towards substrates of interest. Here, we present the development of a screening assay for the substrate specificity of para-phenol oxidases based on the detection of hydrogen peroxide using the ferric-xylenol orange complex method. The assay was used to screen the activity of VAO and EUGO towards a set of twenty-four potential substrates. This led to the identification of 4-cyclopentylphenol as a new substrate of VAO and EUGO and 4-cyclohexylphenol as a new substrate of VAO. Screening of a small library of VAO and EUGO active-site variants for alterations in their substrate specificity led to the identification of a VAO variant (T457Q) with increased activity towards vanillyl alcohol (4-hydroxy-3-methoxybenzyl alcohol) and a EUGO variant (V436I) with increased activity towards chavicol (4-allylphenol) and 4-cyclopentylphenol. This assay provides a quick and efficient method to screen the substrate specificity of para-phenol oxidases, facilitating the enzyme engineering of known para-phenol oxidases and the evaluation of the substrate specificity of novel para-phenol oxidases.
SUBSTITUTED PHENOXYMETHYL DIHYDRO OXAZOLOPYRIMIDINONES, PREPARATION AND USE THEREOF
-
, (2011/04/19)
The present invention relates to a series of substituted phenoxymethyl dihydro oxazolopyrimidinones of formula (I) defined herein. This invention also relates to methods of making these compounds including novel intermediates. The compounds of this invent
Tailoring aqueous solvents for organic reactions: Heck coupling reactions in high temperature water
Gron,Tinsley
, p. 227 - 230 (2007/10/03)
High temperature water is demonstrated to be an effective solvent for Heck coupling reactions of aromatic halides with cyclic alkenes without the addition of co-solvents or specialized ligands. Reactions in the presence of LiCl and quaternary ammonium salts indicate that the reaction takes place in the aqueous phase.
Process for the production of monomeric alkenylphenols from dihydroxydiphenylalkanes
-
, (2008/06/13)
The invention relates to a process for the production of monomeric alkenylphenols from dihydroxydiphenylalkanes by thermal cleavage in certain solvents.
The Thermal ortho-Substitution of Phenols by Vinyl Ethers
Pinhey, John T.,Xuan, Phan Thanh
, p. 69 - 80 (2007/10/02)
Pyrolysis of a mixture of phenol and 3,4-dihydro-2H-pyran (6) at 150-180 deg C resulted in the formation of 2-(tetrahydro-2H-pyran-2-yl)phenol (3a) in moderate yield.This selective ortho-substitution reaction has been investigated for a range of phenols and a number of vinyl ethers.While it was found to be a fairly general reaction for phenols, only with the vinyl ether (6) and 2,3-dihydrofuran (28a) was the reaction found to be regioselective.Aluminium phenylate strongly catalyses the reaction of phenol with (6), which proceeded under these conditions at room temperature.An ene-type mechanism is proposed for the reaction.
REACTION OF PHENOL WITH CYCLOHEXANONE IN THE PRESENCE OF ALUMINUM PHENOLATE
Kozlikovskii, Ya. B.,Chernyaev, B. V.
, p. 1970 - 1973 (2007/10/02)
The reaction of phenol with cyclohexanone in the presence of aluminum phenolate leads to a mixture of products of ether and phenolic character and also a mixture of the dimer and trimer of the initial ketone.As a rule 1-(2-hydroxyphenyl)cyclohexene predominates in the mixture.
Process for the manufacture of new carboxylic acids
-
, (2008/06/13)
α-Phenoxyacetic acids, in which the α-position is substituted by an alkyl residue with 5 to 12 carbon atoms and the phenyl residue is substituted by a cycloaliphatic hydrocarbon residue which is unsaturated in the 1-position and is only singly unsaturated
