Rapid and convenient methods are described for the exhaustive derivatization of carbonyl, carboxyl and hydroxyl groups of prostaglandins and related compounds to methoxime, alkyl ester and alkyl ether compounds respectively. Optimal reaction conditions were established for each group. The reactions were carried out in polar aprotic solvents. Alkyl ester alkyl ether derivatives were obtained quantitatively and rapidly in one step with n-alkyl (C1-C4) halides in the presence of sodium hydroxide. Methyl ester methyl ether derivatives have the highest volatility, but propyl ester propyl ether derivatives improved the separation of complex mixtures. The carbonyl group sometimes induced side-products, so the carbonyl group was converted into methoxime. Methoximation was achieved quantitatively by using methoxylamine in the presence of hydrochloric acid or sodium hydroxide, followed by alkylation in same reaction medium. Methoximation gave syn- and anti-isomers, which were separated chromatographically, decreasing the resolution for complex samples.
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http://dx.doi.org/10.1016/s0021-9673(00)94580-1 | DOI Listing |
Environ Sci Technol
January 2025
Fisheries and Oceans Canada, Pacific Science Enterprise Center, 4160 Marine Drive, West Vancouver, British Columbia V7V 1N6, Canada.
The St. Lawrence Estuary (SLE) beluga () population in Canada is Endangered, and endocrine disrupting contaminants, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and other halogenated flame retardants, have been identified as a threat to the recovery of this population. Here, potential impacts of these contaminants on SLE beluga were evaluated by comparing skin transcriptome profiles and biological pathways between this population and a population less exposed to contaminants (Eastern Beaufort Sea) used as a reference.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Center for Sustainable Catalysis and Engineering, KU Leuven, Celestijnenlaan 200F, Leuven 3001, Belgium.
The local environment of the active site, such as the confinement of hydronium ions within zeolite pores, significantly influences catalytic turnover, similar to enzyme functionality. This study explores these effects in the hydrolysis of guaiacols─lignin-derived compounds─over zeolites in water. In addition to the interesting catechol products, this reaction is advantageous for study due to its bimolecular hydrolysis pathway, which involves a single energy barrier and no intermediates, simplifying kinetic studies and result interpretation.
View Article and Find Full Text PDFJ Org Chem
January 2025
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, Massachusetts, 02155, United States.
This paper describes a series of 12 9,10-dimethoxyanthracene derivatives functionalized with a range of electronically diverse ethynyl substituents at the 2 and 6 positions, aimed at tuning their optoelectronic properties and reactivity with singlet oxygen (O). Optical spectroscopy, cyclic voltammetry, and density functional theory calculations reveal that the ethynyl groups decrease the HOMO-LUMO gaps in these acenes. Notably, bis(dimethylanilineethynyl) substituents increase the wavelength of absorbance onset by over 60 nm compared to 9,10-dimethoxyanthracene (DMA).
View Article and Find Full Text PDFPlant J
January 2025
Unit of Aromatic and Medicinal Plants, Newe Ya'ar Research Center, Volcani Institute, Ramat-Yishay, Israel.
Basil, Ocimum basilicum L., is a widely cultivated aromatic herb, prized for its culinary and medicinal uses, predominantly owing to its unique aroma, primarily determined by eugenol for Genovese cultivars or methyl chavicol for Thai cultivars. To date, a comprehensive basil reference genome has been lacking, with only a fragmented draft available.
View Article and Find Full Text PDFBioorg Chem
January 2025
Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Liaoning Province, Engineering Research Center of Natural Medicine Active Molecule Research & Development, Liaoning Province Key Laboratory of Natural Bioactive Compounds Discovery & Modification, Shenyang, School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, Liaoning 110016, China. Electronic address:
The C-3 and C-5 substituted 20-deoxyingenol monoesters are important active components in Euphorbiaceae plants. Nonetheless, their similar physical properties make them difficult to distinguish. The present study developed fast and efficient rules for identifying the esterification sites of 20-deoxyingenol based on a series of chemical syntheses of monoesters and literature research, utilizing NMR spectroscopy, optical rotation analysis, and chromatographic retention behavior.
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