The cellulose oligomers with different degrees of polymerization (DP), 7, 11, 18, 24, 26, 40 and 52, were prepared by hydrolysis of microcrystalline cellulose with phosphoric acid. These oligomers including the starting microcrystalline cellulose (DP 124) were converted to tris(3,5-dimethylphenylcarbamate) (CDMPC) derivatives by the reaction with an excess of 3,5-dimethylphenyl isocyanate to be used as the chiral stationary phase (CSP) in high-performance liquid chromatography (HPLC). The structures of the CDMPC derivatives were investigated by infrared spectroscopy (IR), ¹H-NMR, circular dichroism (CD) and size exclusion chromatography (SEC), and the DPs of the derivatives estimated by SEC agreed with those estimated by ¹H-NMR. After coating the derivatives on silica gel, their chiral recognition abilities were evaluated using eight racemates under a normal phase condition with a hexane-2-propanol (99/1) mixture as an eluent. The chiral recognition abilities of 7- and 11-mers, particularly the former, were lower than those of the higher oligomers from DP 18 to 52, which had rather similar abilities to that of 124-mer, although the abilities depended on the racemates. DP 18 seems to be sufficient for CDMPC to exhibit chiral recognition similar to that of the CDMPC with larger DPs.
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http://dx.doi.org/10.3390/molecules21111484 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Zhejiang University, Chemistry, Department of Chemistry, ZhiJinGang Campus, 310058, Hangzhou, CHINA.
Integrating two or more materials to construct membranes with heterogeneous pore structures is an effective strategy for enhancing separation performance. Regularly arranging these heterogeneous pores can significantly optimize the combined effect of the introduced components. Porous Organic Cages (POCs), an emerging subclass of porous materials composed of discrete molecules, assemble to form interconnected pores and exhibit permanent porosity in the solid state.
View Article and Find Full Text PDFAnal Chim Acta
February 2025
Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, 0179, Tbilisi, Georgia. Electronic address:
Background: Isotopologues resulting from the labelling of molecules with deuterium have attracted interest due to the isotope effect observed in chemistry and biosciences. Isotope effect may also play out in noncovalent interactions and mechanisms leading to intermolecular recognition. In chromatography, differences in retention time between isotopologues, as well as between isotopomers have been observed resulting in two different elution sequences (isotope effects): the normal isotope effect when heavier isotopologues retain longer than lighter analogues, and the inverse isotope effect featuring the opposite elution order.
View Article and Find Full Text PDFAnal Chim Acta
February 2025
Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, No. 5 Zhongguancun South Street, Beijing, 100081, China. Electronic address:
Background: The metal organic cages (MOCs) are an emerging type of porous material that has attracted considerable research interest due to their unique properties, including good stability and well-defined intrinsic cavities. The chiral MOCs with porous structures have broad application prospects in enantiomeric recognition and separation. However, there are almost no relevant reports on chiral MOCs as chiral stationary phases (CSPs) for enantioseparation by high-performance liquid chromatography (HPLC).
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 10608 Taiwan.
Despite having identical physicochemical properties, chiral molecules require effective separation techniques due to their distinct pharmacological effects. Polysaccharide-based chiral stationary phases (CSPs) are widely used for chiral separations in liquid chromatography; however, the mechanisms of chiral recognition are not well understood. This research explored the adsorption, retention, and chiral recognition mechanisms of three amylose-based CSPs: Chiralpak ID, IF, and IG.
View Article and Find Full Text PDFEur J Med Chem
January 2025
Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China; School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China. Electronic address:
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