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Cancer stands as a serious malady, posing substantial risks to human well‐being and survival. This underscores the paramount necessity to explore and investigate novel antitumor medications. Nitrogen‐containing compounds, especially those derived from natural sources, form a highly significant category of antitumor agents. Among these, antitumor agents with six‐membered aromatic nitrogen heterocycles have consistently attracted the attention of chemists and pharmacologists. Accordingly, we present a comprehensive summary of synthetic strategies and clinical implications of these compounds in this review. This entails an in‐depth analysis of synthesis pathways for pyridine, quinoline, pyrimidine, and quinazoline. Additionally, we explore the historical progression, targets, mechanisms of action, and clinical effectiveness of small molecule inhibitors possessing these structural features. [ABSTRACT FROM AUTHOR]

Molecular aggregation affects the electronic interactions between molecules and has emerged as a powerful tool in material science. Aggregate effect finds wide applications in the research of new physical phenomena; however, its value for chemical reaction development has been far less explored. Herein, we report the development of aggregation‐enabled alkene insertion into carbon–halogen bonds. The spontaneous cleavage of C–X (X = Cl, Br, or I) bonds generates an intimate ion pair, which can be quickly captured by alkenes in an aggregated state. Additional catalysts or promoters are not necessary under such circumstances, and solvent quenching experiments indicate that the aggregated state is critical for achieving such sequences. The ionic insertion mode is supported by mechanistic studies, density functional theory calculations, and symmetry‐adapted perturbation theory analysis. Results also show that the non‐aggregated state may quench the transition state and terminate the insertion process. [ABSTRACT FROM AUTHOR]

Aims: The ubiquilin‐like protein ubiquilin 2 (UBQLN2) is associated with amyotrophic lateral sclerosis and frontotemporal degeneration (ALS/FTD). The biological function of UBQLN2 has previously been shown to be related to stress granules (SGs). In this study, we aimed to clarify the regulatory relationship between UBQLN2 and SGs. Methods: In this study, we transfected UBQLN2‐WT or UBQLN2‐P497H plasmids into cell lines (HEK293T, HeLa), and observed the process of SG dynamics by immunofluorescence. Meanwhile, immunoblot analyses the protein changes of stress granules related components. Results: We observed that ubiquilin 2 colocalizes with the SG component proteins G3BP1, TIA‐1, ATXN2, and PABPC1. In cells expressing WT UBQLN2 or P497H mutants, in the early stages of SG formation under oxidative stress, the percentage of cells with SGs and the number of SGs per cell decreased to varying degrees. Between WT and mutant, there was no significant difference in eIF2α activity after stress treatment. Interestingly, the UBQLN2 P497H mutant downregulates the level of TIA‐1. In addition, the overexpression of the UBQLN2 P497H mutant inhibited the phosphorylation of 4E‐BP1 and affected the nucleoplasmic distribution of TDP‐43. Conclusions: Ubiquilin 2 colocalizes with the SG component proteins G3BP1, TIA‐1, ATXN2, and PABPC1. It participates in regulating SG dynamics. And UBQLN2 mutation affects the assembly of stress granules by regulating TIA‐1. In addition, the overexpression of the UBQLN2 P497H mutant inhibited the phosphorylation of 4E‐BP1 and affected the nuclear and cytoplasmic distribution of TDP‐43. These provide new insights into the role of UBQLN2 in oxidative stress and the pathogenesis of ALS. [ABSTRACT FROM AUTHOR]

This article, titled "Cover Picture: Six-Membered Aromatic Nitrogen Heterocyclic Anti-Tumor Agents: Synthesis and Applications," discusses the synthesis strategies and clinical applications of nitrogen-containing heterocyclic antitumor agents. The cover picture showcases various classes of these antitumor skeletons, including pyridine, quinoline, pyrimidine, and quinazoline. The article provides a detailed review of the small molecule inhibitors based on these scaffolds and their use in the field of anti-tumor research. The authors of the article are Jiatong Li, Ao Gu, Xiao-Mei Nong, Shuyang Zhai, Zhu-Ying Yue, Meng-Yao Li, and Yingbin Liu. [Extracted from the article]