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An intriguing stepwise diradical mechanism of the dimerization of the reactive intermediate (thiocarbonyl -methanide) appearing in the reaction of phenyl selenophen-2-yl thioketone with diazomethane was studied by means of computational methods. The preferred formation of the unusual macroheterocycle, competitive with the 1,3-ring closure leading to a thiirane and the head-to-head dimerization yielding a 1,4-dithiane derivative, respectively, was explained based on the analysis of the structure of the favored conformer of the intermediate, delocalized diradical species. The influence of selenium as a 'heavy atom' for stabilization of this intermediate has been emphasized.
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http://dx.doi.org/10.3762/bjoc.13.44 | DOI Listing |
Ren Fail
December 2025
Department of Critical Care Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, China.
This study aimed to develop a predictive model and construct a graded nomogram to estimate the risk of severe acute kidney injury (AKI) in patients without preexisting kidney dysfunction undergoing liver transplantation (LT). Patients undergoing LT between January 2022 and June 2023 were prospectively screened. Severe AKI was defined as Kidney Disease: Improving Global Outcomes stage 3.
View Article and Find Full Text PDFJ Phys Chem B
September 2025
Department of Physics and Chemistry, DGIST, Daegu 42988, Republic of Korea.
Epidermal growth factor receptor (EGFR) dimerization plays a pivotal role in cellular signaling, influencing proliferation and disease progression, particularly in cancer. Despite extensive studies, the quantitative relationship between EGFR expression levels and dimerization efficiency remains incompletely understood. In this study, we investigated EGFR dimerization kinetics using ensemble-level biochemical assays and single-molecule tracking (SMT) in living cells.
View Article and Find Full Text PDFOrg Biomol Chem
September 2025
Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Pune-410008, India.
A facile and efficient one-pot rongalite-mediated self-dimerization of 3-acylidene-2-oxindoles has been developed for the diastereoselective synthesis of highly functionalized dispirocyclopentanebisoxindoles. The reaction proceeds a domino sequence involving intermolecular Michael addition followed by intramolecular aldol cyclization under basic conditions. Rongalite, an inexpensive and readily available reagent (∼$0.
View Article and Find Full Text PDFInorg Chem
September 2025
Boston University, Chemistry Department, 590 Commonwealth Avenue, Boston, Massachusetts 02215, United States.
Previously published (NMe)[V(O)(μ-O)(pin)], has been shown to aerobically catalyze the oxidation of benzylic and allylic alcohols under mild conditions. Herein, we report syntheses of [V(O)(μ-O)(pin)] trimers, which are also active in OAD catalysis. Trimer formation requires an ammonium cation with at least two hydrogen atoms per cation (e.
View Article and Find Full Text PDFJ Agric Food Chem
September 2025
Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
The -hydroxyphenyl (H) unit is an aromatic structure found in lignin, particularly abundant in compression wood and grass, and is derived from the incorporation of -coumaryl alcohol (-CMA). Although the structural and biosynthetic aspects of lignin have been extensively studied, the polymerization reactivity of H-unit during lignification remains poorly understood. In this study, horseradish peroxidase (HRP)-catalyzed homo- and co-oxidative coupling reactions (initial stage of enzymatic dehydrogenative polymerization) with -CMA and/or coniferyl alcohol (CA) were performed to investigate monolignol consumption, dilignol formation, and their potential involvement in subsequent polymerization.
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