This article discusses the reactivity of 6-azaindazole (1) and 2,6-naphthyridine (2), proposed to be "heteroaromatic rings of the future," which would be useful for fragment-based drug discovery (FBDD) campaigns, developing growth vectors for fragment elaboration by selectively functionalizing different positions on the rings. The pyridone oxygens and pyrazole nitrogen can be functionalized selectively. Arylation at the α-carbon of the pyridone moiety was achieved by a transition metal-free radical cross-coupling using aryl hydrazines. This method proceeded under mild conditions without the need for protection of the hydroxypyridine. Additionally, we developed a method for the regioselective C-3 functionalization of heterocycle 1-sulfonamide rearrangement. This method involved a novel regioselective base-mediated N-C migration of the N-1 sulfonamide to yield the C-3 sulfone. This procedure is also applicable for indazole C-3 functionalization and mechanistic studies of the rearrangement suggest that an intermolecular process is involved. These reactions enable the fragment elaboration of heterocycles 1 and 2 in several growth vectors to facilitate their use in FBDD.
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http://dx.doi.org/10.1039/d2ob00968d | DOI Listing |
Sci Rep
January 2025
State Key Laboratory of Chemical Resources Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
Tyrosine-protein kinase Src plays a key role in cell proliferation and growth under favorable conditions, but its overexpression and genetic mutations can lead to the progression of various inflammatory diseases. Due to the specificity and selectivity problems of previously discovered inhibitors like dasatinib and bosutinib, we employed an integrated machine learning and structure-based drug repurposing strategy to find novel, targeted, and non-toxic Src kinase inhibitors. Different machine learning models including random forest (RF), k-nearest neighbors (K-NN), decision tree, and support vector machine (SVM), were trained using already available bioactivity data of Src kinase targeting compounds.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
December 2024
Jiangsu Dualix Spectral Imaging Co., Ltd. Wuxi 214000, China.
This study aims to establish a rapid and non-destructive method for recognizing the origins and cultivation patterns of Astragali Radix. A hyperspectral imaging system(spectral ranges: 400-1 000 nm, 900-1 700 nm; detection time: 15 s) was used to examine the samples of Astragali Radix with different origins and cultivation patterns. The collected hyperspectral datasets were highly correlated and numerous, which required the establishment of stable and reliable dimension reduction and classification models.
View Article and Find Full Text PDFEnviron Pollut
January 2025
Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia; Faculty of Mechanical Engineering, Brno University of Technology, Brno, Czech Republic. Electronic address:
Tire wear microplastics (TWMs) are continuously generated during driving and are subsequently released into the environment, where they pose potential risks to aquatic organisms. In this study, the effects of untreated, hydrated, and environmentally aged TWMs on the growth, root development, photosynthesis, electron transport system (ETS) activity, and energy-rich molecules of duckweed Lemna minor were investigated. The results indicated that untreated and aged TWMs have the most pronounced negative effects on Lemna minor, as evidenced by reduced growth and impaired root development.
View Article and Find Full Text PDFMicrosc Microanal
January 2025
Université de Lorraine, CNRS, Arts et Métiers, LEM3, Metz 57070, France.
Characterizing threading dislocations (TDs) in gallium nitride (GaN) semiconductors is crucial for ensuring the reliability of semiconductor devices. The current research addresses this issue by combining two techniques using a scanning electron microscope, namely electron channeling contrast imaging (ECCI) and high-resolution electron backscattered diffraction (HR-EBSD). It is a comparative study of these techniques to underscore how they perform in the evaluation of TD densities in GaN epitaxial layers.
View Article and Find Full Text PDFDespite recent advances, improvements to long-term survival in metastatic carcinomas, such as pancreatic or ovarian cancer, remain limited. Current therapies suppress growth-promoting biochemical signals, ablate cells expressing tumor-associated antigens, or promote adaptive immunity to tumor neoantigens. However, these approaches are limited by toxicity to normal cells using the same signaling pathways or expressing the same antigens, or by the low frequency of neoantigens in most carcinomas.
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