10.1016/j.neuropharm.2013.04.020
The research primarily investigates the binding affinity of various flavonoids to the μ-opioid receptor and evaluates the antinociceptive effects of a synthetic flavonoid, 3,3-dibromo?avanone, in mice. The study employs in vitro binding assays using [3H]DAMGO to assess the interaction of different flavonoids with μ-opioid receptors in rat forebrain membranes. The most potent compound, 3,3-dibromo?avanone, is further synthesized and tested in vivo using several pain models, including the acetic acid-induced writhing test, hot plate test, and formalin test, to evaluate its antinociceptive properties. Additional experiments assess potential side effects such as sedation, motor coordination, and gastrointestinal transit inhibition. The synthetic procedure for 3,3-dibromo?avanone is described, and its chemical structure is analyzed using techniques like NMR and EIMS. A series of natural and synthetic flavonoids were tested for their binding affinity to μ-opioid receptors. These included hesperidin, neohesperidin, naringin, rutin, hesperetin, naringenin, flavone, diosmetin, quercetin, apigenin, chrysin, among others. These compounds were obtained from Sigma-Aldrich, Extrasynthese, or were synthesized in the laboratory. The study concludes that 3,3-dibromo?avanone exhibits μ-opioid receptor activation-related antinociceptive effects without significant motor or gastrointestinal side effects, suggesting its potential as an alternative pain treatment.
10.1246/bcsj.36.1272
The study investigates the condensation reactions of isopropylpyrido[3,2-d]tropolones. The researchers explored various reactions involving these compounds. For instance, 8-isopropyl-2-methylpyrido[3,2-d]tropolone and 9-isopropyl-2-methylpyrido[3,2-d]tropolone reacted with benzaldehyde to produce 8-isopropyl-2-styrylpyrido[3,2-d]tropolone (VIa) and 9-isopropyl-2-styrylpyrido[3,2-d]tropolone (VIb) respectively. The compounds Va, Vb, and Vc, which are derivatives of isopropylpyrido[3,2-d]tropolones, reacted with o-phenylenediamine in acetic acid to yield quinoxaline derivatives such as the quinoxalo derivative of 8-isopropylpyrido[3,2-d]tropolone (VIIla) and the quinoxalo derivative of 8-isopropyl-2-methylpyrido[3,2-d]tropolone (VIIIb). Additionally, the reaction of 8-isopropyl-2-methylpyrido[3,2-d]tropolone (XIb) with phenylhydrazine in acetic acid resulted in the formation of yellow crystals (XIIb) with a pyrido[3,2-d]indolo[2,3-b]tropone structure. The study also attempted to prepare quaternary salts of 8-isopropylpyrido[3,2-d]tropolones by reaction with methyl iodide, ethyl iodide, and ethyl p-toluenesulfonate, but these attempts were unsuccessful. The researchers concluded that the condensation products have specific structures based on their observations and spectral data analysis.
10.1016/j.bmc.2014.04.016
The research focuses on the design and discovery of flavonoid-based HIV-1 integrase inhibitors that target both the active site of the enzyme and its interaction with LEDGF/p75. The purpose of this study is to develop novel inhibitors that can combat HIV-1 by inhibiting the viral replication process, specifically the integration of viral DNA into the host genome, which is catalyzed by HIV integrase (IN). The researchers synthesized a series of flavonoid derivatives with the aim of improving the inhibitory activity against IN and disrupting the IN-LEDGF/p75 interaction, which is crucial for viral integration. The study concluded that certain flavonoids, particularly those containing a catechol or β-ketoenol structure, showed potent inhibitory activity against both the catalytic function of IN and the IN-LEDGF/p75 interaction. Notably, the introduction of a hydrophilic morpholine group at the phenolic hydroxyl position resulted in sub- to low-micromolar IN-LEDGF/p75 inhibitory activity. The chemicals used in this process included various flavonoid derivatives, such as quercetin, baicalein, genistein, luteolin, chrysin, apigenin, and naringenin, along with synthetic reagents like acetic anhydride, benzyl bromide, potassium carbonate, and palladium catalysts for the synthesis and modification of these flavonoids.
Xn,
Xi
