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Morphine tolerance (MT) is currently a challenging issue related to intractable pain treatment. Studies have shown that reactive oxygen species (ROSs) derived from NADPH oxidase (NOX) and produced in response to endoplasmic reticulum (ER) stress participate in MT development. However, which NOX subtype initiates ER stress during MT development is unclear. NOX4 is mainly expressed on intracellular membranes, such as the ER and mitochondrial membranes, and its sole function is to produce ROS. Whether NOX4 is activated during MT development and the mechanisms underlying the association between NOX4 and ER stress during this process still need to be confirmed. In our study, we used the classic morphine‐tolerant rat model and evaluated the analgesic effect of intrathecally injected morphine through a hot water tail‐flick assay. Our research demonstrated for the first time that chronic morphine administration upregulates NOX4 expression in the spinal cord by activating three ER stress sensors, protein kinase RNA‐like ER kinase (PERK), inositol‐requiring enzyme 1 (IRE1) and activating transcription factor 6 (ATF6), subsequently leading to the activation of microtubule‐associated protein 1 light chain 3 b (LC3B) and P62 (a well‐known autophagy marker) in GABAergic neurons. Our results may suggest that regulating NOX4 and the key mechanism underlying ER stress or autophagy may be a promising strategy to treat and prevent MT development. [ABSTRACT FROM AUTHOR]

An attractive approach to selective functionalization of remote C−H bonds is a metal/hydride shift/cross‐coupling reaction sequence. Complimentary to the heavily exploited 1,2‐nickel/hydride shift along an sp3 chain, a chain‐walking process, the 1,4‐nickel/hydride shift along an sp2 chain is more complex. Here we report an unprecedented aryl‐to‐vinyl 1,4‐nickel/hydride shift reaction, in which the migratory alkenylnickel species generated in situ is selectively trapped by one of various coupling partners, such as isocyanates, alkyl bromides, aryl chlorides or alkynyl bromides, allowing regio‐ and stereoselective access to trisubstituted alkenes. In contrast to the well‐reported ipso‐aryl coupling reactions, this strategy provides remote alkenyl C−H functionalized products with good yield and with excellent chemo‐, regio‐ and E/Z‐selectivity. [ABSTRACT FROM AUTHOR]

Crystalline thin‐film organic light‐emitting diodes (C‐OLEDs) can achieve a large light emission and a low Joule‐heat loss under low driving voltage due to the high carrier mobility of the crystalline thin films. However, it is urgent for the C‐OLEDs to improve their external quantum efficiency (EQE). Here, a novel strategy is proposed using a doped "hot exciton" material to sensitize a high PLQY blue emitter in C‐OLEDs. Benefiting from the capability of the "hot exciton" material harnessing triplet/singlet excitons, the C‐OLED exhibits an efficiency breakthrough with a maximum EQE of 6.2%, a much enhanced blue photon output with pure blue emission Commission International de L'Eclairage (CIE) (0.14, 0.15), a low turn‐on/operation voltage of 2.6 V(@1 cd m−2)/3.8 V (@1000 cd m−2), and a maximum power efficiency (PE) of 9.4 lm W−1. This work unlocks the potential of C‐OLEDs for achieving high photon output with high EQE. [ABSTRACT FROM AUTHOR]

Regio‐ and enantioselective hydroarylamination, hydroalkylamination and hydroamidation of styrenes have been developed by NiH catalysis with a simple bioxazoline ligand under mild conditions. A wide range of enantioenriched benzylic arylamines, alkylamines and amides can be easily accessed by nitroarenes, hydroxylamines and dioxazolones, respectively as amination reagents. The chiral induction in these reactions is proposed to proceed through an enantiodifferentiating syn‐hydronickellation step. [ABSTRACT FROM AUTHOR]