What's the difference between isomer and naphthoquinone?
Isomer
Definition:
(n.) A body or compound which is isomeric with another body or compound; a member of an isomeric series.
Example Sentences:
(1) An unsaturated fatty acid auxotroph of Escherichia coli was grown with a series of cis-octadecenoate isomers in which the location of the double bond varied from positions 3 to 17.
(2) Fluorination with [18F]acetylhypofluorite yields 6-[18F]fluoro-L-dopa with 95% radiochemical purity; fluorination of the same substrate with [18F]F2 yields a mixture of all three structural isomers in a ratio of 70:16:14 for 6-, 5-, and 2-fluoro compounds.
(3) The cis isomer was retained longer in liver, particularly in mitochondria, but had low retention in that portion of the endoplasmic reticulum isolated as the rough membrane fraction.
(4) The purity and configuration of each isomer of the free acid and N-chloroacetylated derivative were ascertained by: (a) paper chromatography in five solvent systems, (b) elemental analysis, (c) Van Slyke nitrous acid determination of alpha-carbonyl carbon, and (d) Van Slyke ninhydrin determination of alpha-carbonyl carbon, and (e) optical rotation.
(5) The stronger negative potentials may weaken electrostatic receptor interactions and, thereby, cause the trans(E)-isomers to be less active than cis(Z)-isomers.
(6) The identity of each of the three forms was determined by carboxymethylation of the free cysteines in each isomer with [3H]iodoacetic acid followed by determination of the labelled cysteines by tryptic peptide mapping.
(7) In contrast to the enantiomeric discrimination observed with racemic amine, the individual isomers were metabolized at approximately the same rate.
(8) To further assess different binding behavior of these two isomers, association rate was measured.
(9) None of the 3 beta- or 5 beta-isomers had any effect.
(10) Isomers and epimers of glucose influence insulin and cAMP in a parallel fashion as do sulfonylurea compounds (tolbutamide and glibenclamide).
(11) Bioaccumulation experiments were performed on the hexachlorocyclohexane isomers alpha-HCH, beta-HCH, gamma-HCH and delta-HCH, testing them simultaneously.
(12) Although serum total LDH activity was not altered, the LD5 isoenzyme was proportionately higher in the HCH isomers treated animals.
(13) Racemic verapamil and the L- and D-isomer increased cellular vincristine accumulation to the same extent.
(14) The hypothesis that opiate agonism requires an N substituent in the axial position does not appear to be consistent with the increased potency of beta isomers in which axial N substituents are thermodynamically more unstable.
(15) In the case of adducts with the diol-epoxides of benzo[c]phenanthrene, the energetically most favored structures are isomers with significant biological activity.
(16) Liver regeneration was stimulated in male rats with two-thirds of the liver removed by feeding a basal diet supplemented with acetaminophen (0.35-1.5%; weight basis), 2-acetamidophenol (1.0%) and acetophenetidin (1.0%) over a period of 10 days po, but was in the control range with the m-isomer, 3-acetamidophenol (1.0%), N-butyryl-p-aminophenol (1.0%), o-, m- and p-aminophenols (0.50%) and 4-acetamidothiophenol.
(17) However, exposure of the cells to either of the two isomers of azoxy-procarbazine led to significant DNA damage and cytotoxicity.
(18) 1"-Oxobufuralol (3) was reduced with a complex of (2S)-(-)-2-amino-3-methyl-1,1-diphenylbutan-1-ol and borane, yielding 2, which had a 95:5 ratio of the possible 1"R and 1"S isomers as determined by HPLC.
(19) As the two signals had the same intensities, it was suggested that equivalent amounts of cis and trans isomers of the alkenylmether were formed.
(20) The most important recent work has concerned the different anticoagulant potencies and metabolic pathways of the optical isomers of some of these drugs.
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.