This paper reports the first study of the gas-phase intramolecular elimination reaction of steviol glycosides in positive electrospray mass spectrometry. The observed glycosylated product ions are proposed to be formed via an intramolecular elimination of sugar units from the parent molecule ion. It was further proven by MS/MS studies and deuterium labeling experiments with one of the steviol glycosides, rebaudioside A. These mass spectrometric results confirmed that the new glycosylated product ions observed are most likely formed by the combination of glucose moieties (Glu) II-IV and Glu I via a gas-phase intramolecular elimination reaction.
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Plant Cell Rep
January 2025
Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-8589, Japan.
We generated soybean mutants related to two ß-amyrin synthase genes using DNA-free site-directed mutagenesis system. Our results suggested that one of the genes is predominant in the soyasaponin biosynthesis. Soyasaponins, which are triterpenoid saponins contained in soybean [Glycine max (L.
View Article and Find Full Text PDFChem Pharm Bull (Tokyo)
January 2025
Graduate School of Integrated Basic Sciences, Nihon University, 3-25-40 Sakurajosui, Setagaya-ku, Tokyo 156-8550, Japan.
A method for preparing the fused cyclohexane and pyrrolidine portion of the strychnos skeleton has been developed using domino intermolecular and intramolecular S2 cyclization. Using this method, the formation of pyrrolidine proceeded smoothly with good yield without the E2 elimination product. This reaction condition is effective for synthesizing the fused cyclohexane and pyrrolidine portion of the strychnos skeleton.
View Article and Find Full Text PDFRSC Adv
January 2025
Nanoscience Program, Institute of Basic and Applied Sciences, Egypt-Japan University of Science and Technology New Borg El-Arab City Alexandria Egypt
We report herein a facile synthesis, characterization, and the electron transfer reaction of a novel light-harvesting material composed of laser-induced graphene (LIG) functionalized with the photoactive 5,10,15,20-tetrakis(4-trimethylammoniophenyl)porphyrin tetra(-toluenesulfonate) dye (TTMAPP). LIG was easily fabricated on the surface of a polyimide sheet using VersaLASER 3.6 (VLS 3.
View Article and Find Full Text PDFA one-pot, acid-, base-, and metal-free, multicomponent strategy has been developed to synthesize spiro thiochromene-oxindole derivatives as potential anti-inflammatory agents. The synthesized compounds were screened for their anti-inflammatory activity by inhibiting heat-induced Bovine Serum Albumin (BSA) denaturation assay, revealing moderate to good efficacy. Compounds 4e, 4k, and 4h exhibited the highest activity, inhibiting BSA denaturation by 90.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK.
Organofluorine compounds are vital across multiple sectors, hence highly selective methods to install fluorine are of considerable importance. The deoxyfluorination of alcohols is a key approach to prepare organofluorine compounds, however, a highly secondary (2°)-selective deoxyfluorination of alcohols has not been realized to date. Herein, we report that borane-mediated deoxyfluorination results in high 2°-selectivity in inter- and intra-molecular competition reactions versus primary (1°), tertiary (3°) and even benzylic (Bn) alcohols.
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