A new liquid chromatographic method has been developed for the chiral separation of the enantiomers of mandelic acid and their derivatives 2-chloromandelic acid, 4-hydroxymandelic acid, 4-methoxymandelic acid, and 3,4,5-trismethoxymandelic acid. The enantiomers were separated by a CHIRALPAK(®) IC (250 mm×4.6 mm, 5 μm). Mandelic acid, 4-methoxymandelic acid, and 3,4,5-trismethoxymandelic acid were baseline resolved (resolution factor (RS)=2.21, RS=2.14, and RS=3.70, respectively). In contrast, the enantioselectivities between CHIRALPAK(®) IC and 2-chloromandelic acid and 4-hydroxymandelic acid investigated were low. By comparing the chromatographs of mandelic acid enantiomers and mandelic acid spiked with (R)-mandelic acid, it was determined that the first effluent was (R)-mandelic acid.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3709066 | PMC |
http://dx.doi.org/10.1631/jzus.B1200361 | DOI Listing |
Anal Chem
January 2025
School of Petrochemical Engineering, Liaoning Petrochemical University, Fushun 113001, China.
Chiral discrimination is an indispensable tool that has pivotal importance in the assignment of absolute configuration and determination of enantiomeric excess in chiral compounds. A series of enantiomerically pure -1,2-diaminocyclohexane (-DACH)-derived benzamides were first synthesized by simple chemical steps, and 14 variated derivatives have been assessed as NMR chiral solvating agents (CSAs) for discrimination of the signals of mandelic acid (MA) in H NMR analysis. The highly efficient chiral recognition of CSA on different substrates, including MAs, carboxylic acids, amino acid derivatives, and phosphoric acids (32 examples), was expanded via H, F, and P NMR spectroscopy.
View Article and Find Full Text PDFCryst Growth Des
January 2025
School of Chemistry, Analytical and Biological Chemistry Research Facility, SSPC, the SFI Research Centre for Pharmaceuticals, University College Cork, Cork T12 K8AF, Ireland.
The crystal structures of (±)-mandelamide, -mandelamide, and enantioenriched mandelamide (94 : 6 ) were determined. Diastereomeric cocrystal pairs of -mandelamide with both enantiomers of mandelic acid and proline were synthesized. The diastereomeric cocrystal pairs of -mandelamide with /-mandelic acid form 1:1 cocrystals in each case, while the diastereomeric cocrystal pairs of -mandelamide with proline have different stoichiometries.
View Article and Find Full Text PDFInt J Pharm
December 2024
Center for Science of Imperatriz, Federal University of Maranhão - UFMA, 65900-410, Imperatriz, MA, Brazil. Electronic address:
This study reports the synthesis and the experimental-theoretical characterization of a new coamorphous system consisting of ethionamide (ETH) and mandelic acid (MND) as a coformer. The solid dispersion was synthesized using the slow solvent evaporation method in an ethanolic medium. The structural, vibrational, and thermal properties of the system were characterized.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
State Key Laboratory Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhu Road South, Nanjing 211816, China.
The cycloaddition of CO to epoxide (CCE) reactions produce valuable cyclic carbonates useful in the electrolytes of lithium-ion batteries, as organic solvents, and in polymeric materials. However, halide-containing catalysts are predominantly used in these reactions, despite halides being notoriously corrosive to steel processing equipment and residual halides also having harmful effects. To eliminate the reliance on halides as cocatalyst in most CCE reactions, halide-free catalysts are highly desirable.
View Article and Find Full Text PDFMicrob Biotechnol
December 2024
Department of Biochemistry, Molecular Biology and Biophysics and Biotechnology Institute, University of Minnesota, Twin Cities, USA.
A major factor limiting the biodegradation of organofluorine compounds has been highlighted as fluoride anion toxicity produced by defluorinating enzymes. Here, two highly active defluorinases with different activities were constitutively expressed in Pseudomonas putida ATCC 12633 to examine adaption to fluoride stress. Each strain was grown on α-fluorophenylacetic acid as the sole carbon source via defluorination to mandelic acid, and each showed immediate fluoride release and delayed growth.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!