Two mononuclear iron(II) p-semiquinonate (pSQ) complexes have been generated via one-electron reduction of precursor complexes containing a substituted 1,4-naphthoquinone ligand. Detailed spectroscopic and computational analysis confirmed the presence of a coordinated pSQ radical ferromagnetically coupled to the high-spin Fe(II) center. The complexes are intended to model electronic interaction...

A micellar assembly of molecules constituted of poly(ethylene glycol) as the hydrophilic component and 2-diazo-1,2-naphthoquinone as the hydrophobic component was shown to be destroyed in a two-photon photoreaction triggered by infrared light with release of an encapsulated fluorescent probe molecule.

Electron mediation between NAD-dependent enzymes using quinone moieties typically requires the use of a diaphorase as an intermediary enzyme. The ability for a naphthoquinone redox polymer to independently oxidize enzymatically-generated NADH is demonstrated for application to glucose/O2 enzymatic fuel cells.

A study of the antimicrobial compounds from Moneses uniflora resulted in the isolation of a novel compound, 8-chloro-2,7-dimethyl-1,4-naphthoquinone (8-chlorochimaphilin) (1), together with chimaphilin (2) and 3-hydroxychimaphilin (3) as the antimicrobial components. 2,7-Dimethyl-1,3-dihydroxynaphthyl 4-O-alpha-L-rhamnopyranoside (4) and 2,7-dimethoxy-1,4,8-trihydroxynaphthalene (6) were also i...

two simple visible spectrophotometric methods are developed and validated for the quantification of modafinil using 1,2-naphthoquinone-4-sulphonic acid (nqs method) and 2,4-dinitrophenol (dnp method) as analytical reagents. the nqs method involves the reaction of modafinil with 1,2-naphthoquinone-4-sulphonate in alkaline medium at room conditions to form a yellow colored product exhibiting maxi...

A highly efficient and straightforward three-component cascade reaction was developed to synthesize benzo[g]imidazo[1,2-a]quinolinedione derivatives from heterocyclic ketene aminals (HKAs), aldehydes, and 2-hydroxy-1,4-naphthoquinone (HNQ) via Et(3)N-catalyzed tandem [3 + 2 + 1] annulation under solvent-free conditions. The reactions were very mild, convenient and highly regioselective to form ...

Three photochemical reactions were investigated under solar irradiation conditions with moderately concentrated sunlight: the photoacylation of naphthoquinone with butyraldehyde and the dye-sensitized photooxygenations of citronellol and 1,5-dihydroxynaphthalene, respectively. All reactions were easily performed on multigram-to-kilogram scales using cheap and commercially available starting mat...

In a new propolis type, red Brazilian propolis, 14 compounds were identified (six of them new for propolis), among them simple phenolics, triterepenoids, isoflavonoids, prenylated benzophenones and a naphthoquinone epoxide (isolated for the first time from a natural source). Three of the major components demonstrated significant antimicrobial activity, and two (obtained as inseparable mixture) ...

erosclerotic lesions. VSMC proliferation induced by growth factors, such as platelet-derived growth factor (PDGF), is known to be a prerequisite of the intimal thickening that is observed after angioplasty, and mitogen-activated protein kinases (MAPKs) are considered to be a critical step in the proliferation of VSMCs. Pyles et al. reported that MAPKs are activated in response to balloon stretc...

Levels of glutathione (GSH) in tumour tissue may be important in determining the clinical response to certain anticancer agents. Recent reports have suggested that D,L-buthionine-S,R-sulphoximine (BSO), a specific inhibitor of GSH synthesis, may be used to deplete tumour cell GSH and thus increase the therapeutic ratio of these agents. We have previously shown that 1-naphthol is a potential ant...