The preparative chromatographic resolution of racemic mixtures is rapidly becoming a standard approach for the generation of enantiomers in pharmaceutical R&D. This paper will discuss the optical resolution of a pharmaceutical intermediate as the separation is scaled up from the milligram to the kilogram scale. Difficulties encountered and their solutions at each scale will be discussed. In addition, the exploration of Simulated Moving Bed (SMB) for the separation will also be discussed. Finally, a comparison of the productivities and solvent consumption for each method and scale will be presented.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s0021-9673(99)00470-7 | DOI Listing |
J Chromatogr B Analyt Technol Biomed Life Sci
January 2025
Resorcinol is a widespread substance used in a large variety of manufacturing industries, including cosmetics, with endocrine-disrupting activity on the thyroid function. The aim of the present study was to develop and validate a sensitive, selective and robust method to quantify resorcinol in urine and thereby assess hairdressers' occupational exposure. As resorcinol is mainly excreted in urine as glucuronide or sulfate forms, the first step consisted in hydrolyzing urine samples with a β-glucuronidase-arylsulfatase enzyme for 16 h.
View Article and Find Full Text PDFPharmaceutics
January 2025
BK21 FOUR KNU Community-Based Intelligent Novel Drug Discovery Education Unit, College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Daegu 41566, Republic of Korea.
: Although donepezil, a reversible acetylcholinesterase inhibitor, has been in use since 1996, its metabolic characteristics remain poorly characterized. Therefore, this study aims to investigate the in vivo metabolism of donepezil using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) based on a molecular networking (MN) approach integrated with a non-targeted metabolomics approach. : After the oral administration of donepezil (30 mg/kg) in rats, urine, feces, and liver samples were collected for LC-HRMS analysis.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Faculty of Pharmaceutical Sciences, University of Iceland, 107 Reykjavik, Iceland.
Exploring tazarotene, a third-generation retinoid for potential hand osteoarthritis treatment, this study presents the development and validation of an ultra-performance liquid chromatography with quadrupole detector mass spectrometry (UPLC-QDa) method for the simultaneous quantification of tazarotene and tazarotenic acid, its active metabolite, in porcine skin. Method development involved a design-of-experiments approach for chromatographic optimization of gradient steepness, organic solvent volume, column temperature, capillary voltage, flow rate, and cone voltage. Central composite orthogonal design was used to optimize peak area, peak width, retention time, and resolution.
View Article and Find Full Text PDFCell
January 2025
University of Chinese Academy of Sciences, Beijing, China; Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China. Electronic address:
The cerebral cortex and hippocampus are crucial brain regions for learning and memory, which depend on activity-induced synaptic plasticity involving N-methyl-ᴅ-aspartate receptors (NMDARs). However, subunit assembly and molecular architecture of endogenous NMDARs (eNMDARs) in the brain remain elusive. Using conformation- and subunit-dependent antibodies, we purified eNMDARs from adult rat cerebral cortex and hippocampus.
View Article and Find Full Text PDFChemistry
January 2025
Tianjin Normal University, Chemistry, No393 west Binshui Road, Tianjin, CHINA.
Achieving the adsorptive separation and chromatographic separation of industrially the important chemicals toluene and methylcyclohexane using the same material is a highly desirable goal. We have successfully accomplished this using a fluorinated macrocycle tetrafluoroterphen[3]arene (4FTP3), which was synthesized and used for gas chromatographic separation in our previous work. The macrocycle 4FTP3 permitted the adsorptive separation of toluene from a toluene/methylcyclohexane mixture (1:1, v/v) with a purity of 99.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!