3-Amino-5-phenyl (or 5-methyl)-1,4-benzodiazepin-2-ones, which are chiral precursors of anti-respiratory syncytial virus active agents, were resolved on three different chiral stationary phases (CSPs) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid or (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6. Among the three CSPs, the CSP that is based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 and containing residual silanol group-protecting n-octyl groups on the silica surface was found to be most effective with the use of 80% ethanol in water containing perchloric acid (10 mM) and ammonium acetate (1.0 mM) as a mobile phase. The separation factors (α) and resolutions (R(S) ) were in the range of 1.90-3.21 and 2.79-5.96, respectively. From the relationship between the analyte structure and the chromatographic resolution behavior, the chiral recognition mechanism on the CSP based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid was proposed to be different from that on the CSP based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6. In addition, the chromatographic resolution behavior of the most effective CSP was investigated as a function of the composition of aqueous mobile phase containing organic and acidic modifier and ammonium acetate.
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http://dx.doi.org/10.1002/chir.22041 | DOI Listing |
Biomed Chromatogr
February 2025
Department of Pharmaceutical Chemistry and Analysis, ISF College of Pharmacy, Moga, Punjab, India.
Enantioseparation and enantiorecognition are crucial in the pharmaceutical analysis of chiral substances, impacting safety, efficacy, and regulatory compliance. Enantioseparation refers to the process of separating enantiomers from a mixture, typically achieved through chromatography techniques like HPLC and SFC. In contrast, enantiorecognition involves the identification of enantiomers based on their interaction with a chiral selector without the need for separation.
View Article and Find Full Text PDFSci Rep
January 2025
Egyptian Drug Authority (EDA), Giza, 35521, Egypt.
The present study applied a combined analytical quality-by-design and green analytical chemistry approach to develop an HPLC method for the determination of four cephalosporin pharmaceuticals in both their formulations and water samples. These drugs include ceftriaxone, cefotaxime, ceftazidime and cefoperazone. A Box-Behnken experimental design was employed to optimize three chromatographic parameters: mobile phase composition, flow rate and buffer pH.
View Article and Find Full Text PDFChemosphere
December 2024
Department of Civil, Urban, Earth, and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:
Pine needle, pine bark, and soil samples were collected from various regions in South Korea, considering the suitability of vegetation samples as passive samplers. A total of 27 organochlorine pesticides (OCPs) were analyzed using a gas chromatograph/high-resolution mass spectrometer (GC/HRMS). The total concentrations of OCPs ranged between 650 and 3652 pg/g dw in soil, 215 and 1384 pg/g ww in pine needles, and 456 and 1723 pg/g ww in pine bark.
View Article and Find Full Text PDFSe Pu
January 2025
Research Center for Eco-Environmental Engineering, Dongguan University of Technology, Dongguan 523808, China.
Halogenated organic pollutants (HOPs) have attracted considerable attention owing to their persistence, bioaccumulation, and toxicity. The development of methods to detect HOPs in fish is challenging owing to the compositional complexity of fish matrices, which contain high levels of lipids and relatively low concentrations of HOPs. In addition, the lipophilicity of most HOPs renders their extraction difficult.
View Article and Find Full Text PDFInt J Exp Pathol
December 2024
Department of Ageing, Rheumatology and Regenerative Medicine, Division of Medicine, The Rayne Building, University College, London, UK.
Using a model of UV-killed E. coli driven dermal inflammation in healthy human volunteers, we originally reported that following inflammatory resolution there was infiltration of macrophages, which, through prostanoids including prostaglandin (PG) E, imprints long-term tissue immunity. In addition to the prostanoids, data on levels of Specialised Pro-Resolution Lipid Mediators (SPMs) throughout inflammatory onset, resolution and post-resolution phases of this model were presented, but as illustrations rather than as primary data.
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