Solid-phase synthesis of quinolinone library

Step-economical synthesis of 3-amido-2-quinolones by dendritic copper powder-mediated one-pot reaction

The one-pot protocol by the dendritic copper powder-mediated Knoevenagel condensation/annelation is delineated here for the synthesis of 3-amido-2-quinolones. It is practical with moisture tolerance and easy setup, and is compatible with many functional groups under mild conditions. This method was applied for the preparation of the key intermediates of biologically relevant 3-amido-2-quinolones.

Analysis of two novel 1-4 quinolinone structures with bromine and nitrobenzyl ligands

The scientific community has shown particular interest in the study of quinolinones-a class of bicyclic organic compounds. An example of these compounds are the 4-quinolinones, considered to be very useful building blocks, since they can adapt their molecular structures with different ligands for applications in various fields such as pharmacy, medicine, physics and engineering. The compounds (E)-3-(benzylidene)-2-(3-nitrophenyl)-2,3-dihydro-1-(phenylsulfonyl)-quinolin-4-(1H)-one (NFQ) and (E)-3-(benzylidene)-2-(4-bromophenyl)-2,3-dihydro-1-(phenylsulfonyl) quinolin-4-(1H)-one (BFQ) were synthesized and characterized by infrared spectroscopy, ¹H and ¹³C NMR, and melting point. NFQ crystallized in the orthorhombic Pbca space group while BFQ appears in the monoclinic P2₁/n space group. X-ray diffraction was used to evaluate their crystallographic structures, and Hirshfeld surface evaluates the intermolecular interactions, supramolecular arrangement and packaging. Theoretical vibrational assignments and calculated electronic properties also demonstrate acceptable agreement between experimental and theoretical results.

Synthesis and structure-activity relationships of quinolinone and quinoline-based P2X7 receptor antagonists and their anti-sphere formation activities in glioblastoma cells

Screening a compound library of quinolinone derivatives identified compound 11a as a new P2X7 receptor antagonist. To optimize its activity, we assessed structure-activity relationships (SAR) at three different positions, R₁, R₂ and R₃, of the quinolinone scaffold. SAR analysis suggested that a carboxylic acid ethyl ester group at the R₁ position, an adamantyl carboxamide group at R₂ and a 4-methoxy substitution at the R₃ position are the best substituents for the antagonism of P2X7R activity. However, because most of the quinolinone derivatives showed low inhibitory effects in an IL-1β ELISA assay, the core structure was further modified to a quinoline skeleton with chloride or substituted phenyl groups. The optimized antagonists with the quinoline scaffold included 2-chloro-5-adamantyl-quinoline derivative (16c) and 2-(4-hydroxymethylphenyl)-5-adamantyl-quinoline derivative (17k), with IC₅₀ values of 4 and 3 nM, respectively. In contrast to the quinolinone derivatives, the antagonistic effects of the quinoline compounds (16c and 17k) were paralleled by their ability to inhibit the release of the pro-inflammatory cytokine, IL-1β, from LPS/IFN-γ/BzATP-stimulated THP-1 cells (IC₅₀ of 7 and 12 nM, respectively). In addition, potent P2X7R antagonists significantly inhibited the sphere size of TS15-88 glioblastoma cells.