What's the difference between naphthalene and naphthoquinone?
Naphthalene
Definition:
(n.) A white crystalline aromatic hydrocarbon, C10H8, analogous to benzene, and obtained by the distillation of certain bituminous materials, such as the heavy oil of coal tar. It is the type and basis of a large number of derivatives among organic compounds. Formerly called also naphthaline.
Example Sentences:
(1) The formation of 1-naphthol from naphthalene was investigated in rat brain 105,000 g particulate fraction.
(2) Synthesis of hexabromonaphthalenes (HBNs) by direct bromination of naphthalene results in a mixture of two isomers.
(3) Trospectomycin sulphate, a novel analogue of spectinomycin, was compared to spectinomycin, tetracycline, lincosamide, macrolide, quinolone and naphthalenic ansamycin-class antibiotics for in-vitro activity against Mycoplasma pneumoniae, M. hominis and Ureaplasma urealyticum.
(4) After prolonged adaptation of strain BN6 to growth on 6A2NS, this organism readily converted all naphthalene-2-sulfonates with OH- or NH2-substituents in the 5-, 6-, 7-, or 8-position.
(5) In contrast to wild-type F1 adenosine triphosphatase, the beta subunits of soluble ATPase from Escherichia coli mutant strains AN120 (uncA401) and AN939 (uncD412) were not labeled by the fluorescent thiol-specific reagents 5-iodoacetamidofluorescein, 2-(4'-iodoacetamidoanilino)naphthalene-6-sulfonic acid or 4-[N-(iodoacetoxy)ethyl-N-methyl]amino-7-nitrobenzo-2-oxa-1,3-diazole.
(6) In all cases, naphthalene was metabolised to a covalently bound product(s) and to two major methanol-soluble products, which co-chromatographed with 1-naphthol and 1,2-dihydro-1,2-dihydroxynaphthalene.
(7) The degradation of 3- and 4-HBs by these strains is therefore analogous to the metabolism of biphenyl, 2-HB, and naphthalene in the requirement for 2,3-catechol formation.
(8) The gamma-crystallin fractions II, III and IV from calf eye lens were treated with the thiol-specific fluorescent probe 2-(4'-maleimidylanilino)naphthalene-6-sulfonate (MIANS), in order to determine the reactivity of the seven (gamma-II) or six (gamma-III, gamma-IV) cysteine residues.
(9) Pinwheel inclusions (PWs) were found in cells of callus tissue derived from explants of secondary phloem parenchyma of carrot (Daucus carota) storage root and grown on a basal medium containing zeatin and indoleacetic acid or coconut milk, naphthalene acetic acid, or combinations of these.
(10) The organic portion of this structure demonstrates near-C2 symmetry with a pseudo-twofold axis coincident with the central C-C naphthalene ring bond.
(11) The m-xylene-adapted microorganisms in the aquifer column degraded toluene, benzaldehyde, benzoate, m-toluylaldehyde, m-toluate, m-cresol, p-cresol, and p-hydroxybenzoate but were unable to metabolize benzene, naphthalene, methylcyclohexane, and 1,3-dimethylcyclohexane.
(12) The absorbed and in the urine excreted 14C-activities are measured with a scintillation spectrophotometer and scintillator composed of 2,5-diphenyloxazole(POP), 1,4-bis-(4-methyl-5-phenyl-2-oxazolyl)benzene (dimethyl-POPOP), naphthalene, toluene and ethyleneglycol monomethylether.
(13) To examine this question in detail, intracellular glutathione levels were monitored in mouse hepatocytes incubated in the presence of various concentrations of naphthalene.
(14) A proprietary insecticidal mulesing powder containing diazinon and an experimental liquid dressing based on eucalyptus oil, naphthalene, cresylic acid and chlorfenvinphos in a carrier of liquid hydrocarbons and petroleum oil were compared for their ability to promote wound healing and reduce the incidence of fly strike in freshly mulesed lambs.
(15) Rates of mineralization were observed, as follows, for [14C]hexadecane greater than [14C]naphthalene greater than [14C]toluene greater than [14C]cyclohexane.
(16) Salicylic acid which accumulated as a product of naphthalene catabolism in the cultural broth of the wild strain was found to undergo further oxidation by the population of growing cells.
(17) Previous studies have demonstrated the formation of three glutathione conjugates during the hepatic and pulmonary microsomal metabolism of naphthalene in the presence of reduced glutathione and cytosolic enzymes containing the glutathione transferases.
(18) The ability of P. putida, strain NCIB 9816, to grow with naphthalene (Nah+) and salicylate (Sal+) is correlated with the presence of an 83 kilobase (kb) conjugative plasmid (pDTG1).
(19) Adjacent organic anions are separated by the Li+ ions and their coordination polyhedra, with the water molecules occupying positions above and below the naphthalene rings and participating in a three-dimensional hydrogen-bonded network.
(20) The minor isomer is definitively identified as 2,3,4,5,6,7-HBN by high-field nuclear magnetic resonance (NMR) spectroscopic analysis of brominated [1-13C]naphthalene-derived products.
Naphthoquinone
Definition:
(n.) A yellow crystalline substance, C10H6O2, analogous to quinone, obtained by oxidizing naphthalene with chromic acid.
Example Sentences:
(1) A comparison of the antioxidant activities of eight 1,4-naphthoquinones indicated that methyl substitution of C-2, lack of steric hindrance at C-3 or C-5, and (in the case of weak acids) a relatively high pKa are favorable structural features associated with strong antioxidant activity.
(2) 2-Dimethylamino-3-chloro-1,4-naphthoquinone (DCNQ) is bound to microsomal cytochrome P-450 as a type I substrate (lambda max = 391 nm, lambda min = 420 nm).
(3) The positive inotropic effect of 2,3-dimethoxy-1,4-naphthoquinone was completely catecholamine-mediated, that of 2-methyl-1,4-naphthoquinone was approximately 70% adrenergic and 30% direct.
(4) Hepa 1c1c7 murine hepatoma cells are plated in 96-well microtiter plates, grown for 24 h, and exposed to inducing agents for another 24 h. The cells are then lysed and quinone reductase activity is assayed by the addition of a reaction mixture containing an NADPH-generating system, menadione (2-methyl-1,4-naphthoquinone), and MTT [3-(4,-5-dimethylthiazo-2-yl)-2,5-diphenyltetrazolium bromide].
(5) At 10 microM, naphthoquinone caused an increase in specific activity of the enzyme DT-diaphorase.
(6) On the basis of these studies the novel quinone is shown to be 2,5 and 6- or 2,7 and 8-trimethyl-3-farnesylfarnesyl-1,4-naphthoquinone.
(7) Synthetic heterocyclic quinones (107 samples) consisting of o- and p-quinoline quinones, o-isoquinoline quinones and p-quinoxaline quinones as well as o- and p-naphthoquinones (3 samples) were tested for their inhibitory activities against avian myeloblastosis virus reverse transcriptase (AMV-RT) and cytotoxic activities against mouse lymphoblastoma L5178Y cells.
(8) The potential was found to shift to a less noble state when the system of the chlorophyll-naphthoquinone electrode was inserted into NAD solution with illumination.
(9) Unlike guinea pig, 2,3-dimethoxy-1,4-naphthoquinone had no effect in rat tissue.
(10) All six of these recently named Campylobacter species contained menaquinone-6 (MK-6), but only C. hyointestinalis and "C. upsaliensis" contained 2,[5 or 8]-dimethyl-3-farnesyl-farnesyl-1,4-naphthoquinone (*MK-6), a previously described novel menaquinone of the Campylobacter genus.
(11) Previous studies have indicated that the presence of cytotoxic levels of menadione (2-methyl-1,4-naphthoquinone) causes rapid changes in intracellular thiol and Ca2+ homeostasis in isolated rat hepatocytes.
(12) nodulating cowpeas, and R. phaseoli derived from cultures susceptible to tetramethylthiuram disulfide (thiram), 2,3-dichloro-1,4-naphthoquinone (phygon), and 2,3,5,6-tetrachloro-p-benzoquinone (spergon), respectively, grew in the presence of high concentrations of the fungicides and converted them to products not toxic to the sensitive rhizobia.
(13) An FMN-dependent NADH-quinone reductase is induced in Escherichia coli by growing the cells in the presence of menadione (2-methyl-1,4-naphthoquinone).
(14) Oxidation of 9 by activated manganese dioxide gave the naphthoquinone 11.
(15) DT-diaphorase catalysed the reduction of 1,4-naphthoquinones with hydroxy, methyl, methoxy and glutathionyl substituents at the expense of reducing equivalents from NADPH.
(16) Series of (1,4)-Naphthoquinono(3,2-c)-1H-pyrazoles and 2-substituted amino-1,4-naphthoquinones have been synthesised and studied for their possible anticancer activity (animal tumours, Walker 256 carcinosarcoma), Influenza RNA transcriptase activity, antibiotic activity (C. neoformans, T. mentagraphytes, M. canis, A. niger, and C. albicans).
(17) generated by benzo- and naphthoquinones in guinea pig and rat heart and the extent of catecholamine-dependent positive inotropic effect was evident.
(18) In the presence of 2-N-methyl-amino-1,4-naphthoquinone in octane, acting as electron acceptor, the negative charges were transferred from water to octane following the oxidation of NADH, succinate and ascorbate.
(19) In a Triton X-100 solubilized carboxylase system, it was found that the naphthoquinone ring structure is essential for activity, as is the 2-methyl group.
(20) 2-Methoxy-1,4-naphthoquinone was found to be a potent oxidative compound, generating hydrogen peroxide in erythrocytes and causing both methemoglobin formation and glutathione depletion in the absence of glucose.