1-Hy-droxy-4-prop-yloxy-9,10-anthra-quinone, C17H14O4, (I), and its acetyl derivative, 4-acet-yloxy-4-prop-yloxy-9,10-anthra-quinone, C19H16O5, (II), were synthesized from the commercially available dye quinizarin. In both compounds, the anthra-quinone frameworks are close to planarity. There is a large difference in the conformation of the prop-yloxy group; the mol-ecule of (I) adopts a gauche...

The title compound, C(12)H(18)N(2)O(4)·H(2)O, was obtained as a product of the reaction of hydro-quinone with n-propanol amine. The compound crystallizes as a monohydrate, integrating water into its hydrogen-bonded network. Each diamino-quinone moiety forms two centrosymmetric 10-membered rings through C=O⋯H-N bonds. The resulting bands along [102] are inter-linked through hy-droxy groups and w...

Nanostructured materials with tunable structures and functionality are of interest in diverse areas. Herein, metal ions coordinated quinones through metal-acetylacetone coordination bonds to generate a class structurally tunable, universally adhesive, hydrophilic, pH-degradable materials. A library metal-quinone networks (MQNs) is produced from five model quinone ligands paired nine ions, leadi...

The transfer of electrons and protons between membrane-bound respiratory complexes is facilitated by lipid-soluble redox-active quinone molecules (Q). This work presents a structural analysis of the quinone-binding site (Q-site) identified in succinate:ubiquinone oxidoreductase (SQR) from Escherichia coli. SQR, often referred to as Complex II or succinate dehydrogenase, is a functional member o...

In this work, we measured the metal-binding sites of natural and synthetic dihydroxyindole (DHI) melanins and their respective interactions with Fe(III) ions. Besides the two acid groups detected for the DHI system: catechol (Cat) and quinone-imine (QI), acetate groups were detected in the natural oligomer by potentiometric titrations. At acidic pH values, Fe(III) complexation with synthetic me...

NAD(P)H quinone oxidoreductase (NQO1), an obligatory two-electron reductase, is a ubiquitous cytosolic enzyme that catalyzes the reduction of quinone substrates. The NQO1- mediated two-electron reduction of quinones can be either chemoprotection/detoxification or a chemotherapeutic response, depending on the target quinones. When toxic quinones are reduced by NQO1, they are conjugated with glut...

Exposure to polycyclic aromatic hydrocarbons (PAHs) in the food chain is the major human health hazard associated with the Deepwater Horizon oil spill. Phenanthrene is a representative PAH present in crude oil, and it undergoes biological transformation, photooxidation, and chemical oxidation to produce its signature oxygenated derivative, phenanthrene-9,10-quinone. We report the downstream met...