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Phosphazene base, P2-tBu, efficiently catalyzed the telescopic three-component reaction of diethyl phosphite, cinnamonitrile derivatives, and N-Boc imines, providing β-aminophosphonates having a tetrasubstituted carbon in a highly diastereoselective manner. The reaction involves the little-known 1,1-difunctionalization of an electron-deficient alkene, offering a new format for the three-component reaction under Brønsted base catalysis. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of two distinct novel series of compounds, [II]n and [V]n, containing 1,3,4-thiadiazole units, were studied in this work. The central core of the first series is phenyl, whereas the central core of the second series is OCH2CH2O. FTIR,1HNMR,13CNMR, and mass spectroscopy are used to characterize the materials used in this investigation. Liquid crystalline properties were confirmed by the use of differential scanning calorimeter (DSC) and hot-stage polarizing optical microscopy (POM). While other compounds showed no liquid crystalline behavior, the compounds [II]3–[II]6, [V]1and [V]n showed enantiotropic nematic and smectic phases. [ABSTRACT FROM AUTHOR]

The magnesium-mediated addition of bromoform to conjugated electron-deficient alkenes and imines, such as para -quinone methides (p -QMs) and aurone-derived azadienes, respectively, is reported here for the first time. While p -QMs undergo exclusive and hitherto unreported 1,6-addition of bromoform to afford benzylic tribromomethylated diarylmethanes, aurone-derived azadienes undergo both 1,2- and 1,4-additions to furnish α- and γ-tribromomethylamines. A mechanism involving the intermediacy of the tribromomethyl radical has been proposed based on control experiments and EPR studies. Representative synthetic transformations have also been carried out. [ABSTRACT FROM AUTHOR]

A dearomatization-guided and (3+2) cycloaddition-triggered annulation reaction of in situ formed isoquinolinium ylides with sulfamate-derived cyclic imines is reported, offering a cogent synthesis of tetracyclic 1,3-benzoxazepine frameworks in high yields. The protocol features successive ring-forming and ring-breaking events in a cascade fashion and is also scalable. [ABSTRACT FROM AUTHOR]

Three environmentally friendly Z-scheme CoPc/alkali metal-doped g-C 3 N 4 heterojunction composites were fabricated via in-situ immobilizing cobalt phthalocyanine (CoPc) on the surface of alkali metal-doped g-C 3 N 4 nanosheet by simple hydrothermal method. These composites acted as efficient and recyclable heterogeneous photocatalysts realized that the highly selective aerobic oxidation of amines to the corresponding imines coupling of hydrogen peroxide generation at room temperature. Under irradiation by LED lamp, the imines and H 2 O 2 were obtained with conversion ranges from 87.9 % to 92.0 %, selectivity more than 99 %, and production rate ranges from 3.27 to 3.40 mmol g−1 h−1, respectively. Based on the mechanistic analysis and characterization, the excellent catalytic activity derived from the Z-scheme mechanic and synergistic effect originated from O 2 reduction and amine oxidation. On completion, after centrifugation, washing with solvent and drying under vacuum, the catalysts can be recovered and reused for five successive cycles of testing with a slight decrease in reactivity. For this work, a promising photo synthesis pathway with merits of mild, low-cost, pollution-free, and energy-saving was developed to produce imines coupling with H 2 O 2 generation. [Display omitted] • Three environmentally friendly Z-scheme CoPc/K/Na/PCN-1-3 heterojunction composites were fabricated via in-situ immobilizing planar cobalt phthalocyanine (CoPc) on the surface of K/Na-doped g-C 3 N 4 nanosheet by simple hydrothermal. • A strong build-in electric field was fabricated in these heterojunction composites, which not only could significantly boosts the separation rate and transfer efficiency of photogenerated h+/e-, but also further to raise the redox capacity of h+ and e-. • CoPc/K/Na/PCN-1-3 served as recyclable photocatalysts exhibited high catalytic activity to drive amines oxidation coupled with H 2 O 2 production under visible light in O 2 or air surroundings, N -benzylidenebenzylamine was obtained with a conversion more than 99% and produce nearly stoichiometric H 2 O 2 under at room temperature using ethanol as solvent. [ABSTRACT FROM AUTHOR]

Acetaminophen is commonly used as a reference hepatotoxin to demonstrate that in vitro human liver platforms can emulate features of clinical drug-induced liver injury. However, the induction of substantial cell death in these models typically requires acetaminophen concentrations (∼10 mM) far higher than blood concentrations of the drug associated with clinical hepatotoxicity (∼1 mM). Using the cytochrome P450 inhibitor 1-aminobenzotriazole, we show that acetaminophen toxicity in cultured human, mouse, and rat hepatocytes is not dependent on N-acetyl-p-benzoquinonimine formation, unlike the in vivo setting. This finding highlights the limitation of using acetaminophen as a reference hepatotoxin for the evaluation of in vitro liver models. Hence, we make recommendations on the selection of reference hepatotoxins for this purpose., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society of Toxicology.)