A novel solid-phase strategy allows the efficient preparation of "traceless" sulfahydantoins. A total of 28 derivatives, with crude purity generally higher than 85%, were prepared by parallel synthesis. Through reductive alkylations, Mitsunobu reactions, and sulfamoylation reactions on oxime resin, the synthetic strategy affords sulfahydantoin derivatives selectively substituted at N(2), N(5) and N(2), N(5) positions, although yields of disubstituted compounds are lower. The mild reaction conditions involved lead to sulfahydantoins without racemization.
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http://dx.doi.org/10.1021/cc010073u | DOI Listing |
Molecules
December 2024
Laboratório de Ciências Forenses e Psicológicas Egas Moniz, Molecular Pathology and Forensic Biochemistry Laboratory, Egas Moniz Center for Interdisciplinary Research, Egas Moniz School of Health and Science, Quinta da Granja, 2829-511 Almada, Portugal.
The present work reports the development, optimization, and validation, of a methodology to determine lidocaine, procaine, tetracaine, and benzocaine in urine matrices. Two extractive preconcentration techniques, solid-phase microextraction (SPME) LC Tips and bar adsorptive microextraction (BAμE), were studied and applied to the four target anesthetics, followed by gas chromatography-mass spectrometry (GC-MS) analysis. Several parameters that could affect microextraction and back-extraction were optimized using two different designs of experiments (Box-Behnken and full-factorial) to maximize extraction efficiency from aqueous media.
View Article and Find Full Text PDFAnal Bioanal Chem
January 2025
State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, 214122, China.
Ofloxacin is a commonly used quinolone antibiotic that is also used as a feed supplement in livestock production and in plant disease prevention and treatment. However, the excessive use and abuse of ofloxacin will accumulate along the food chain and endanger human health. Therefore, the development of a simple, rapid, and sensitive detection method for the determination of ofloxacin is critical.
View Article and Find Full Text PDFMikrochim Acta
January 2025
School of Public Health, Hebei Key Laboratory of Occupational Health and Safety for Coal Industry, North China University of Science and Technology, No. 21 Bohai Road, Caofeidian, Tangshan, 063210, Hebei, China.
Biochars (BCs) derived from waste-branches of apple tree, grape tree, and oak were developed for direct solid-phase extraction (SPE) of five benzodiazepines (BZDs) in crude urine samples prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination. Scanning electron microscopy, elemental analyzer, X-ray diffractometry, N adsorption/desorption experiments, and Fourier transform infrared spectrometry characterizations revealed the existence of their mesoporous structure and numerous oxygen-containing functional groups. The obtained BCs not only possessed high affinity towards BZDs via π-π and hydrogen bond interactions, but also afforded the great biocompatibility of excluding interfering components from undiluted urine samples when using SPE adsorbents.
View Article and Find Full Text PDFFood Chem
December 2024
Institute of Food Safety, Chinese Academy of Inspection and Quarantine, Beijing 100176, China; Key Laboratory of Food Quality and Safety for State Market Regulation, Chinese Academy of Inspection and Quarantine, Beijing 100176, China. Electronic address:
An innovative core-shell covalent organic framework (COF), FeO@COF (ETTBA-ND), was synthesized through a facile and energy-efficient method. This adsorbent facilitated magnetic solid phase extraction (MSPE) of six AFs prior to LC-MS/MS analysis, achieving one-step purification and enrichment in food matrices. The successful synthesis of the adsorbent was confirmed using various techniques, with adsorption capacities ranging from 46.
View Article and Find Full Text PDFRSC Chem Biol
December 2024
Department of Chemistry, Texas A&M University College Station Texas 77843 USA
Despite the growing interest in mirror-image l-oligonucleotides, both as a robust nucleic acid analogue and as an artificial genetic polymer, their broader adoption in biochemical research and medicine remains hindered by challenges associated with the synthesis of long sequences, especially for l-RNA. Herein, we present a novel strategy for assembling long l-RNAs the joining of two or more shorter fragments using cross-chiral ligase ribozymes together with new substrate activation chemistry. We show that 5'-monophosphorylated l-RNA, which is readily prepared by solid-phase synthesis, can be activated by chemical attachment of a 5'-adenosine monophosphate (AMP) or diphosphate (ADP), yielding 5'-adenosyl(di- or tri-)phosphate l-RNA.
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