20266-62-0Relevant articles and documents
One-Pot Biocatalytic Double Oxidation of α-Isophorone for the Synthesis of Ketoisophorone
Tavanti, Michele,Parmeggiani, Fabio,Castellanos, J. Rubén Gómez,Mattevi, Andrea,Turner, Nicholas J.
, p. 3338 - 3348 (2017/09/13)
The chemical synthesis of ketoisophorone, a valuable building block of vitamins and pharmaceuticals, suffers from several drawbacks in terms of reaction conditions and selectivity. Herein, the first biocatalytic one-pot double oxidation of the readily available α-isophorone to ketoisophorone is described. Variants of the self-sufficient P450cam-RhFRed with improved activity have been identified to perform the first step of the designed cascade (regio- and enantioselective allylic oxidation of α-isophorone to 4-hydroxy-α-isophorone). For the second step, the screening of a broad panel of alcohol dehydrogenases (ADHs) led to the identification of Cm-ADH10 from Candida magnoliae. The crystal structure of Cm-ADH10 was solved and docking experiments confirmed the preferred position and geometry of the substrate for catalysis. The synthesis of ketoisophorone was demonstrated both as a one-pot two-step process and as a cascade process employing designer cells co-expressing the two biocatalysts, with a productivity of up to 1.4 g L?1 d?1.
Remote ester group leads to efficient kinetic resolution of racemic aliphatic alcohols via asymmetric hydrogenation
Yang, Xiao-Hui,Wang, Ke,Zhu, Shou-Fei,Xie, Jian-Hua,Zhou, Qi-Lin
supporting information, p. 17426 - 17429 (2015/02/02)
A highly efficient method for kinetic resolution of racemic aliphatic alcohols without conversion of the hydroxyl group has been realized; the method involves hydrogenation mediated by a remote ester group and is catalyzed by a chiral iridium complex. This powerful, environmentally friendly method provides chiral δ-alkyl-δ-hydroxy esters and δ-alkyl-1,5-diols in good yields with high enantioselectivities even at extremely low catalyst loading (0.001 mol %).
Compositions of iodophenoxy alkanes and iodophenyl ethers in combination with cellulose derivatives for visualization of the gastrointestinal tract
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, (2008/06/13)
Disclosed are x-ray contrast compositions for oral or retrograde examination of the gastrointestinal tract comprising an iodophenoxy alkane, iodophenyl alkenylalkyl ether or an iodophenyl alkynylalkyl ether x-ray producing agent in combination with a cellulose derivative in a pharmaceutically acceptable carrier; and methods for their use in diagnostic radiology of the gastrointestinal tract.
Compositions of iodophenoxy alkanes and iodophenyl ethers and pharmaceutically acceptable clays for visualization of the gastrointestinal tract
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, (2008/06/13)
Disclosed are x-ray contrast compositions for oral or retrograde examination of the gastrointestinal tract comprising iodophenoxy alkanes and iodophenyl ethers as the x-ray producing agents in combination with a pharmaceutically acceptable clay in a pharmaceutically acceptable carrier; and methods for their use in diagnostic radiology of the gastrointestinal tract.
Compositions of iodophenoxy alkanes and iodophenyl ethers in film-forming materials for visualization of the gastrointestinal tract
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, (2008/06/13)
Disclosed are x-ray contrast compositions for oral or retrograde examination of the gastrointestinal tract comprising a polymeric material capable of forming a coating on the gastrointestinal tract and an x-ray producing agent of the formula STR1 and meth
Aliphatic Propargylamines: Potent, Selective, Irreversible Monoamine Oxidase B Inhibitors
Yu, Peter H.,Davis, Bruce A.,Boulton, Alan A.
, p. 3705 - 3713 (2007/10/02)
A series of aliphatic propargylamine derivatives has been synthesized.Some of them possess highly potent, irreversible, selective, inhibitory activity toward monoamine oxidase B (MAO-B).The potency of the inhibitors is related to chain length and substitution of a hydrogen on the terminal carbon of the aliphatic chain.MAO inhibitory activity as assessed in vitro increased as the aliphatic carbon chain length increased.Substitution of a hydrogen by hydroxyl, carboxyl, or carbethoxyl groups at the aliphatic chain terminal or replacement of the methyl group on thenitrogen atom by an ethyl group considerably reduced the inhibitory activity.Stereospecific effects were observed with the R-(-)-enantiomer being 20-fold more active than the S-(+)-enantiomer.Inhibitors with relatively short carbon chain lengths (i.e. four to six carbons) were found to be more potent than those with longer chains in inhibiting brain MAO-B activity in vivo especially after oral administration.Chronic administration of low doses of the aliphatic propargylamines caused a slight cumulative inhibition of MAO-A activity in the mouse brain.These MAO-B inhibitors appear to be nontoxic, and they do not possess an amphetamine-like moiety in their structure as is the case for deprenyl.We expect that these aliphatic propargylamines may be useful in the treatment in certain neuropsychiatric disorders.
Enzymatic Resolution of Medium-Ring Lactones. Synthesis of (S)-(+)-Phoracantholide I
Fouque, Elie,Rousseau, Gerard
, p. 661 - 666 (2007/10/02)
The horse liver and pig liver esterase hydrolysis of racemic medium ring lactones gives with excellent enantiomeric excess the S- (or R) lactones and the corresponding R- (or S) hydroxy acids.This is the first general method to obtain optically pure medium ring lactones.Application to the preparation of (S)-(+)-Phoracantholide I is reported.
Reductive Cyclization of Ketoesters Utilizing Sodium Cyanoborohydride: Synthesis of γ- and δ-Lactones
Podraza, Kenneth F.
, p. 293 - 295 (2007/10/02)
A new one pot procedure to synthesize γ- and δ-lactones, in a 76-84percent yield, is accomplished by the reductive cyclization of 1,4- and 1,5-ketoesters, utilizing sodium cyanoborohydride.The procedure is generally applicable to a wide variety of ketoesters with the exception of the ethyl ester of alkyl 1,5-ketoesters and α,β-unsaturated 1,4- and 1,5-ketoesters.
