The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Coating cellulose tris (3,5‐dimethylphenylcarbamate) (CDMPC) on silica gels with large pores have been demonstrated as an efficient way for the preparation of chiral stationary phase (CSP) for high‐performance liquid chromatography (HPLC). During the process, a number of parameters, including the type of coating solvent, amount of coating, and the method for subsequent solvent removing, have been...
The drug chirality is attracting increasing attention because of different biological activities, metabolic pathways, and toxicities of chiral enantiomers. The chiral separation has been a great challenge. Optimized high‐performance liquid chromatography (HPLC) methods based on vancomycin chiral stationary phase (CSP) were developed for the enantioseparation of propranolol, atenolol, metoprolol, venlafaxine,...
New chiral porphyrin imine was synthesized from (S)‐3‐benzyl‐2‐methyl‐4‐phenylbutanal according to dipyrromethane method using trifluoroacetic acid, BF3 etherate, and p‐chloranil. Manganese complex of this chiral porphyrin imine ligand was used as catalyst in the asymmetric epoxidation of styrene derivatives possessing different substituents. Styrene derivatives possessing electron withdrawing groups...
The enantiomeric purity of escitalopram oxalate ESC and its “in‐process impurities,” namely, ESC‐N‐oxide, ESC‐citadiol, and R(−)‐enantiomer were studied in drug substance and products using high‐performance liquid chromatography (HPLC)‐UV (Method I), synchronous fluorescence spectroscopy (SFS) (Method IIA), and first derivative SFS (Method IIB). Method I describes as an isocratic HPLC‐UV for the direct...
Paclobutrazol (PBZ) is a kind of chiral pesticide, which is a plant growth regulator and has fungicidal activity. Because of the steric‐hindrance effect, there are two enantiomers (2S, 3S; 2R, 3R) in the production. This research studied on the dissipation behavior of chiral pesticide PBZ in the brine during the Chinese cabbage pickled process by phase column‐high performance liquid chromatography...
Prothioconazole is a type of broad‐spectrum triazole thione fungicide developed by the Bayer Company. Prothioconazole‐desthio is the main metabolite of prothioconazole in the environment. In our study, enantiomeric separation of prothioconazole and prothioconazole‐desthio was performed on various chiral stationary phases (CSPs) by high‐performance liquid chromatography (HPLC). It was found that polysaccharide...
In this study, a total of 10 bacterial strains were screened for their ability to reduce cyclohexyl(phenyl)methanone 1 to its corresponding alcohol. Among these strains, Lactobacillus paracasei BD101 was found to be the most successful biocatalyst to reduce the ketones to the corresponding alcohols. The reaction conditions were systematically optimized for the reducing agent L paracasei BD101, which...
A sensitive chiral high performance liquid chromatography (HPLC) method for the determination of aliphatic primary amino alcohol isomers with o‐phthaldialdehyde/mercaptoethanol precolumn derivatization has been developed and validated. Seven chiral columns were tested in a reversed phase mode. Excellent enantioseparation with the resolution more than 2.0 was achieved on Chiralcel OJ‐3R. The effect...
In order to use the enantioseparation capability of cationic cyclodextrin and to combine the advantages of capillary electrochromatography (CEC) with open‐tubular (OT) column, in this study, a new OT‐CEC, coated with cationic cyclodextrin (1‐allylimidazolium‐β‐cyclodextrin [AI‐β‐CD]) as chiral stationary phase (CSP), was prepared and applied for enantioseparation. Synthesized AI‐β‐CD was characterized...
Acute myocardial infarction (AMI) is one of the most severe cardiovascular diseases in humans, often resulting in unexpected death. Early detection is critical for patient survival. Sandwich ELISA is a common method for the detection of AMI. However, ELISA kits from different manufacturers can give different results, in part because of the lack of standardized epitopes. Therefore, the purpose of this...
Green chemistry comprises a new approach in the synthesis of biologically active compounds using biocatalysts, thus diminishing the hazards for human health and environmental pollution. Asymmetric bioreduction is one of the most widely employed strategies in chemoenzymatic synthesis to produce enantiomerically pure chiral alcohols. The present study highlights the use biocatalyst Daucus carota for...
Herein, we disclose the design of a model Ni(II) complex of glycine Schiff base possessing single‐nitrogen stereogenic center, which was successfully used for high‐performance liquid chromatography (HPLC)‐assisted assessment of its configurational stability. The major finding is that the configurational stability of the Ni(II)‐coordinated nitrogen is profoundly dependent on the reaction conditions...
A novel type of oxacalix[2]arene[2]triazine‐based organocatalysts for asymmetric Michael reactions are reported for the first time. Chiral subunits were attached to the heteroatom‐bridged calixaromatic platform by a reaction of (R)‐ and (S)‐1‐aminotetraline with tetraoxacalix[2]arene[2]triazine in both enantiomeric forms. To evaluate the catalytic efficiency of the novel organocatalysts, isobutyraldehyde...
Luminescent lanthanide (III) ions have been exploited for circularly polarized luminescence (CPL) for decades. However, very few of these studies have involved chiral samarium (III) complexes. Complexes are prepared by mixing axial chiral ligands (R/S))‐2,2’‐bis(diphenylphosphoryl)‐1,1′‐binaphthyl (BINAPO) with europium and samarium Tris (trifluoromethane sulfonate) (Eu (OTf)3 and Sm (OTf)3). Luminescence‐based...
Louis Pasteur discovered the phenomenon of molecular chirality, based on his studies of tartrate crystals. His finding remains one of the most important discoveries in the history of chemistry and a fundamentally important chemical phenomenon, with essential implications in biology. In his 1995 book The Private Science of Louis Pasteur, the eminent historian of science Gerald L. Geison (1943‐2001)...
Lipase‐catalysed enantioselective acetylation and deacetylation routes were investigated to prepare 1,5,6‐trisubstituted 7‐oxabicyclo[2.2.1]hept‐2‐ene skeleton in enantio‐pure form. The racemic alcohol (6) used in acetylation reaction was accessed through Diels‐Alder reaction of TBDMS‐protected furfuryl alcohol with maleic anhydride, followed by reduction‐benzylation‐desilylation sequence. After systematic...
Economic and enantioselective synchronous fluorescence spectroscopy and high‐performance thin‐layer chromatography methods have been developed and validated as per ICH guidelines for the separation of zopiclone enantiomers using L‐(+)‐tartaric acid as a chiral selector, followed by determination of the chiral‐switching eszopiclone. Synchronous fluorescence spectroscopy was successfully applied for...
Two independent statistical models for evaluating the certainties of configurational assignments of compounds based on nuclear magnetic resonance (NMR) data are evaluated and compared. Both methods yield weights or probabilities with which two or more structure models (constitutional or configurational isomers or even conformers) could be differentiated based on experimental parameters. Although this...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.