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T lymphocytes (T cells) are essential for tumor immunotherapy. However, the insufficient number of activated T cells greatly limits the efficacy of tumor immunotherapy. Herein, we proposed an oncolytic virus‐mimicking strategy to enhance T cell recruitment and activation for tumor treatment. We constructed an oncolytic virus‐like nanoplatform (PolyIC@ZIF‐8) that was degraded in the acidic tumor environment to release PolyIC and Zn2+. The released PolyIC exhibited an oncolytic virus‐like function that induced tumor cell apoptosis and promoted T cell recruitment and activation through a tumor antigen‐dependent manner. More importantly, the released Zn2+ not only enhanced T cell recruitment by inducing CXCL9/10/11 expression but also promoted T cell activation to increase interferon‐γ (INF‐γ) expression by inducing the phosphorylation of ZAP‐70 via a tumor antigen‐independent manner. This Zn2+‐enhanced oncolytic virus‐mimicking strategy provides a new approach for tumor immunotherapy. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed asymmetric aryl C−P cross‐coupling/cyclization reaction was successfully developed via dynamic kinetic asymmetric transformation (DYKAT) under mild conditions. This study provides a general and simple method for the catalytic enantioselective synthesis of stable six‐, seven‐ and eight‐membered P‐stereogenic phosphorus heterocycles with excellent enantioselectivities and moderate to high yields. One‐pot gram‐scale asymmetric synthesis of the P‐stereogenic P‐heterocycle from commercially available materials was also successfully accomplished with excellent enantioselectivity and high yield. [ABSTRACT FROM AUTHOR]

Although reactive oxygen species (ROS)‐mediated tumor treatments are predominant in clinical applications, ROS‐induced protective autophagy promotes cell survival, especially in hypoxic tumors. Herein, X‐ray triggered nitrite (NO2−) is used for hypoxic prostate cancer therapy by inhibiting autophagy and inducing nitrosative stress based on an electrophilic zeolitic imidazole framework (ZIF‐82‐PVP). After internalization of pH‐responsive ZIF‐82‐PVP nanoparticles, electrophilic ligands and Zn2+ are delivered into cancer cells. Electrophilic ligands can not only consume GSH under hypoxia but also capture low‐energy electrons derived from X‐rays to generate NO2−, which inhibits autophagy and further elevates lethal nitrosative stress levels. In addition, dissociated Zn2+ specifically limits the migration and invasion of prostate cancer cells through ion interference. In vitro and in vivo results indicate that ZIF‐82‐PVP nanoparticles under X‐ray irradiation can effectively promote the apoptosis of hypoxic prostate cancer cells. Overall, this nitrosative stress‐mediated tumor therapy strategy provides a novel approach targeting hypoxic tumors. [ABSTRACT FROM AUTHOR]

Redox homeostasis is one of the main reasons for reactive oxygen species (ROS) tolerance in hypoxic tumors, limiting ROS‐mediated tumor therapy. Proposed herein is a redox dyshomeostasis (RDH) strategy based on a nanoplatform, FeCysPW@ZIF‐82@CAT Dz, to disrupt redox homeostasis, and its application to improve ROS‐mediated hypoxic tumor therapy. Once endocytosed by tumor cells, the catalase DNAzyme (CAT Dz) loaded zeolitic imidazole framework‐82 (ZIF‐82@CAT Dz) shell can be degraded into Zn2+ as cofactors for CAT Dz mediated CAT silencing and electrophilic ligands for glutathione (GSH) depletion under hypoxia, both of which lead to intracellular RDH and H2O2 accumulation. These "disordered" cells show reduced resistance to ROS and are effectively killed by ferrous cysteine‐phosphotungstate (FeCysPW) induced chemodynamic therapy (CDT). In vitro and in vivo data demonstrate that the pH/hypoxia/H2O2 triple stimuli responsive nanocomposite can efficiently kill hypoxic tumors. Overall, the RDH strategy provides a new way of thinking about ROS‐mediated treatment of hypoxic tumors. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed asymmetric aryl C−P cross‐coupling/cyclization reaction was successfully developed via dynamic kinetic asymmetric transformation (DYKAT) under mild conditions. This study provides a general and simple method for the catalytic enantioselective synthesis of stable six‐, seven‐ and eight‐membered P‐stereogenic phosphorus heterocycles with excellent enantioselectivities and moderate to high yields. One‐pot gram‐scale asymmetric synthesis of the P‐stereogenic P‐heterocycle from commercially available materials was also successfully accomplished with excellent enantioselectivity and high yield. [ABSTRACT FROM AUTHOR]

The local electron density of an atom is one key factor that determines its chemical properties. Regulating electron density can promote the atom's reactivity and so reduce the reaction activation energy, which is highly desired in many chemical applications. Herein, we report an intra‐crystalline electron lever strategy, which can regulate the electron density of reaction centre atoms via manipulating ambient lattice states, for Fenton activity improvement. Typically, with the assistance of ultrasound, the Mn4+−O−Fe3+ bond in BiFe0.97Mn0.03O3 perovskite nanocrystals can drive valence electrons and free electrons to accumulate on Fe atoms by a polarization electric field originated from the designed lattice strain. The increase of electron density significantly improves the catalytic activity of Fe, decreasing the activation energy of BiFe0.97Mn0.03O3‐mediated Fenton reaction by 52.55 %, and increasing the.OH yield by 9.21‐fold. This study provides a new way to understand the sono‐Fenton chemistry, and the increased.OH production enables a highly effective chemodynamic therapy. [ABSTRACT FROM AUTHOR]