94347-45-2Relevant academic research and scientific papers
Di(1-naphthyl) methanol ester of carboxylic acids for absolute stereochemical determination
Zhang, Jun,Sheng, Wei,Gholami, Hadi,Nehira, Tatsuo,Borhan, Babak
supporting information, p. 141 - 146 (2017/11/13)
The absolute stereochemistry of chiral carboxylic acids is determined as a di(1-naphthyl)methanol ester derivative. Computational scoring of conformations favoring either P or M helicity of the naphthyl groups, capable of exciton-coupled circular dichroic coupling, leads to a predicted stereochemistry for the derivatized carboxylic acids.
Comparative molecular field analysis of fenoterol derivatives interacting with an agonist-stabilized form of the β2-adrenergic receptor
Plazinska, Anita,Pajak, Karolina,Rutkowska, Ewelina,Jimenez, Lucita,Kozocas, Joseph,Koolpe, Gary,Tanga, Mary,Toll, Lawrence,Wainer, Irving W.,Jozwiak, Krzysztof
, p. 234 - 246 (2014/01/17)
The β2-adrenergic receptor (β2-AR) agonist [3H]-(R,R′)-methoxyfenoterol was employed as the marker ligand in displacement studies measuring the binding affinities (Ki values) of the stereoisomers of a series of 4′-methoxyfenoterol analogs in which the length of the alkyl substituent at α′ position was varied from 0 to 3 carbon atoms. The binding affinities of the compounds were additionally determined using the inverse agonist [3H]-CGP-12177 as the marker ligand and the ability of the compounds to stimulate cAMP accumulation, measured as EC50 values, were determined in HEK293 cells expressing the β2-AR. The data indicate that the highest binding affinities and functional activities were produced by methyl and ethyl substituents at the α′ position. The results also indicate that the Ki values obtained using [3H]-(R,R′)-methoxyfenoterol as the marker ligand modeled the EC50 values obtained from cAMP stimulation better than the data obtained using [3H]-CGP-12177 as the marker ligand. The data from this study was combined with data from previous studies and processed using the Comparative Molecular Field Analysis approach to produce a CoMFA model reflecting the binding to the β2-AR conformation probed by [3H]-(R,R′)-4′-methoxyfenoterol. The CoMFA model of the agonist-stabilized β2-AR suggests that the binding of the fenoterol analogs to an agonist-stabilized conformation of the β2-AR is governed to a greater extend by steric effects than binding to the [3H]-CGP-12177-stabilized conformation(s) in which electrostatic interactions play a more predominate role.
A substrate-driven approach to determine reactivities of α,β-unsaturated carboxylic esters towards asymmetric bioreduction
Tasnádi, Gábor,Winkler, Christoph K.,Clay, Dorina,Sultana, Nargis,Fabian, Walter M. F.,Hall, Mélanie,Ditrich, Klaus,Faber, Kurt
supporting information; experimental part, p. 10362 - 10367 (2012/10/08)
The degree of C=C bond activation in the asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases was studied, and general recommendations to render these "borderline-substrates" more reactive towards enzymatic reduction are proposed. The concept of "supported substrate activation" was developed. In general, an additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates, and α-cyano groups showed little effect. The alcohol moiety of the ester functionality was found to have a strong influence on the reaction rate. Overall, activities were determined by both steric and electronic effects. Biotransformation: The asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases could be tuned by varying the degree of C=C bond activation (see scheme). An additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates. Copyright
Amber-woody scent: Alcohols with divergent structure present common olfactory characteristics and sharp enantiomer differentiation
Margot, Christian,Simmons, Dana P.,Reichlin, Daniel,Skuy, David
, p. 2662 - 2684 (2007/10/03)
Only one out of the four possible trans isomers of the important perfumery alcohol Norlimbanol (1) possesses a very strong amber-woody smell, the isomer 1A with (1′ R,3S,6'S) absolute configuration. Its enantiomer 1B is almost odorless and devoid of amber-woody character, whereas the diastereoisomers 1C and 1D are considerably weaker and perceptible only by the most-sensitive persons. The same is true for a whole series of perceptual analogs of 1, including β-alkoxy alcohols. These ethers belong to two structural classes: [(2,2,6-trimethylcyclohexyl)oxy]- (see 3, 4, and 16) or {[2-(tert-butyl)cyclohexyl]oxy)alkan-2-ol derivatives (see 19 and 20; Table). A superimposition model allowing for good overlap of the respective hydroxylated side chains offers a tentative explanation for the shared perceptual characteristics of the two classes (Fig. 5). The lipophilic cyclohexane moieties present only a minimal overlap in this model, suggesting that quite larger molecules might possess the same smell. (S)-Configured β-alkoxy alcohols can conveniently be obtained on a larger scale by enantioselective reduction of the corresponding ketones (Scheme 9).
Enzymatic hydrolysis and selective racemisation reactions of α-chloro esters
Haughton, Louise,Williams, Jonathan M. J.
, p. 943 - 946 (2007/10/03)
The kinetic resolution of α-chloro esters was effected with good selectivity using CLEC (Cross-Linked Enzyme Crystals) enzymes. The selective racemisation of α-chloro esters in the presence of α-chloro acids enabled a successful dynamic kinetic resolution reaction to be performed.
The acylphosphonate function as an activating and masking moiety for the α-chlorination of fatty acids
Stevens, Christian,De Buyck, Laurent,De Kimpe, Norbert
, p. 8739 - 8742 (2007/10/03)
α-Chloroacylphosphonates were prepared in situ by chlorination of acylphosphonates using sulfuryl chloride and were subsequently cleaved to the corresponding α-chlorinated fatty acids with hydrogen peroxide - sodium bicarbonate.
Asymmetric Synthesis of 2-Chloro- and 2-Bromo-alkanoic acids by Halogenation of α-D-Glucofuranose-Derived Silyl Ketene Acetals.
Angibaud, P.,Chaumette, J. L.,Desmurs, J. R.,Duhamel, L.,Ple, G.,et al.
, p. 1919 - 1932 (2007/10/03)
Optically active (S)-2-bromo- and 2-chloro-alkanoic acids 6 and 7 have been obtained via the diastereoselective halogenation of chiral silyl ketene acetals 3a-f, and subsequent saponification of the resulting crude esters.Examples characterized by e.e. values up to 95percent are reported.The diastereoface selectivity is independent of the silyl ketene acetal E/Z configuration.
Asymmetric Transformation of 2-Phenyl- and 2-Chloroalkanoic Acids via Chiral Oxazolines
Shibata, Saizo,Matsushita, Hajime,Kaneko, Hajime,Noguchi, Masao,Saburi, Masahiko,Yoshikawa, Sadao
, p. 3546 - 3551 (2007/10/02)
Asymmetric transformation of racemic 2-phenyl- and 2-chloroalkanoic acids via oxazolines into the corresponding optically active acids was investigated using (S)-phenylalaninol as a chiral auxiliary.The asymmetric transformation was performed by metalatio
Chlorination of Carboxylic Acid Derivatives. VIII. Liquid Phase Chlorination of the Aliphatic C5-Carboxylic Acids and Their Chlorides, Methyl Esters and Chloromethyl Esters with Chlorine
Kornonen, Ilpo O. O.
, p. 467 - 474 (2007/10/02)
The chlorination of pentanoic, 3-methylbutanoic, 2-methylbutanoic and 2,2-dimethylpropanoic acids and their derivatives with chlorine in the liquid phase have been investigated.The monochloro products formed were determined by gas-liquid chromatography (GLC) and gas-liquid chromatography-mass spectrometry (GLC-MS) as their esters through the comparison with authentic samples.The deactivation of position 2 decreases in the order COCl > CO2H > CO2CH2Cl > CO2CH3, the effect of the COCl-group in pentanoic acid derivatives being 4.3 times stronger than that of the CO2CH3-group.The deactivation is smallest in 2-methylbutanoic acid derivatives owing to the electron-donating methyl group.The EI mass spectra of the methyl and chloromethyl esters have been studied in detail.
