The scope and mechanistic implications of the direct transformation of heterocyclic N-oxides to 2-trifluoromethyl-, and related perfluoroalkyl- and perfluoroaryl-substituted N-heterocycles has been studied. The reaction is effected by perfluoroalkyl- and perfluorophenyltrimethylsilane in the presence of strong base. In situ displacement of the para-fluoro substituent in the pentafluorophenyl ring and the methoxy group in 8-methoxyquinolines with additional nucleophiles allows for further site-selective refunctionalization of the N-heterocyclic products.
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http://dx.doi.org/10.1039/c4ob01088d | DOI Listing |
J Nat Prod
January 2025
Pharmacognosy Institute and Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois Chicago, Chicago, Illinois 60612, United States.
To date, quantitative analysis of proanthocyanidin (PAC) containing materials including plant extracts and fractions depends on colorimetric assays or phloroglucinolysis/thiolysis combined with UV-HPLC analysis. Such assays are of limited accuracy, particularly lack specificity, require extensive sample preparation and degradation, and need appropriate physical reference standards. To address this analytical challenge and toward our broader goal of developing new plant-sourced biomaterials that chemically and mechanically modulate the properties of dental tissue for clinical interventions, we have characterized 12 different PAC DESIGNER (Depletion and Enrichment of Select Ingredients Generating Normalized Extract Resources) materials.
View Article and Find Full Text PDFJ Mol Histol
January 2025
Department of Structural and Functional Biology, University of Campinas (UNICAMP), Campinas, SP, Brazil.
This study investigated tempol action on genes and miRNAs related to NFκB pathway in androgen dependent or independent cell lines and in TRAMP model in the early and late-stages of cancer progression. A bioinformatic search was conducted to select the miRNAs to be measured based on the genes of interest from NFκB pathway. The miR-let-7c-5p, miR-26a-5p and miR-155-5p and five target genes (BCL2, BCL2L1, RELA, TNF, PTGS2) were chosen for RT-PCR and gene enrichment analyses.
View Article and Find Full Text PDFJ Nanobiotechnology
January 2025
Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City, Biological Science Research Center, Southwest University, Chongqing, 400715, China.
Significant progress has been made in the development of potential therapies for diseases associated with inflammation and oxidative stress. Nevertheless, the availability of effective clinical treatments remains limited. Herein, we introduce a novel silk-based bioactive material, TPSF, developed by sequentially conjugating Tempol and phenylboronic acid pinacol ester to silk fibroin.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials, Liaoning Collaborative Innovation Center for Lignocellulosic Biorefinery, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China. Electronic address:
Uncontrolled release of active agents in active packaging reduces antimicrobial efficacy, hindering the effective protection of perishable products from microbial infection. Herein, a novel defective engineering was proposed to design defective and hollow ZIF-8 structures grown on TEMPO oxidized cellulose nanofibrils (TOCNFs) and use them as fast-reacting nanocarriers for loading and controlled release curcumin (Cur) in sodium alginate (SA) active packaging systems (CZT-Cur-SA). By employing stable chelation between tannic acid (TA) and ZIF-8 zinc ions, the connections between zinc ions and imidazole ligands were severed to form a loose and hollow structure, which facilitates the rapid reaction and release of active ingredients triggered by pH changes in the microenvironment.
View Article and Find Full Text PDFFree Radic Biol Med
February 2025
Laboratory of Cellular and Molecular Biology (LBCM), Team Biotechnology and System Biology, Faculty of Biological Sciences, University of Sciences and Technology Houari Boumediene (USTHB), Bab-Ezzouar, Algiers, Algeria. Electronic address:
Oral squamous cell carcinoma (OSCC) is a disabling tumor with poor response to chemotherapy. Here, we sought to explore a new chemotherapeutic approach based on a combined induction of cytotoxic ROS and targeting of autophagy and aerobic glycolysis as central contributors to OSCC carcinogenesis and chemoresistance. To this end, tongue OSCC was generated in BALB/c mice using 4NQO.
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