(n.) The radical (CO)'', occuring, always combined, in many compounds, as the aldehydes, the ketones, urea, carbonyl chloride, etc.
Example Sentences:
(1) The rhodamine 123-induced growth inhibition was partially reversed by treating the dye-pre-exposed infected erythrocytes with the proton ionophore carbonyl-cyanide m-chlorophenylhydrazone, which dissipates transmembrane proton gradients.
(2) 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.
(3) The enzyme was inhibited by thiol and carbonyl reagents.
(4) We studied the localization of carbonyl reductase (E.C.
(5) Both adiphenine.HCl and proadifen.HCl form more stable complexes, suggesting that hydrogen bonding to the carbonyl oxygen by the hydroxyl-group on the rim of the CD ring could be an important contributor to the complexation.
(6) This structure is further characterized by approaches of both the carbonyl and the furan O atoms to ring H atoms with separations which are slightly less than the sum of the relevant van der Waals radii.
(7) Cimaterol at 10-100 nM concentrations reduced cathepsin B benzyloxy-carbonyl-Arg-Arg-4-methyl-7-coumarylamide hydrolyzing activity, as well as benzyloxycarbonyl-Phe-Arg-4-methyl-7-coumarylamide hydrolysis, which is a substrate for both cathepsin B and cathepsin L. Maximum effect was observed after 6-16 h treatment.
(8) An additional synthetic analog of RA, which lacks a carbonyl group at the diketopiperazine ring, exhibited the same uptake rates as ferric RA.
(9) This series of compounds includes [R-(R*,R*)]-4-[[2-[[3-(1H-indol-3-yl)-2-methyl-1-oxo-2- [[(tricyclo[3.3.1.1] dec-2-yloxy)carbonyl]amino]propyl]amino]-1-phenylethyl]amino]- 4-oxobutanoic acid (CI-988, 1, Figure 1), the first rationally designed non-peptide antagonist of a neuropeptide receptor.
(10) Highly resolved signals are observed in the carbonyl stretching frequency region of the light-induced FTIR spectra.
(11) In compounds with other substituents that promote activity, C-6 alpha substitution with -CH3, -Cl, or -Br strongly enhances activity; -F, -OCH3, carbonyl, or the unsubstituted compound promotes weak binding; and -OC2H5, -OAc, -OCOOCH3, or -OH eliminates binding activity.
(12) Since the activity of canrenone is 38% that of spironolactone, introduction of the carbonyl group at the 15 position of canrenone resulted in a reduction in activity.
(13) Treatment with carbonyl iron reduced monocyte concentration to less than 1.2% in all donors, as measured by morphologic criteria, esterase staining and ingestion of latex particles.
(14) Our data do not support the possibility of hydrogen bonding between the 16 beta-hydroxyl of gitoxigenin and the lactone ring, previously suggested to account for the decreased activity of gitoxigenin vis à vis digitoxigenin, but, rather, suggest that the decreased activity may be due to an intramolecular hydrogen bond between the hydroxyls on C-14 and C-16 and an unusual D-ring conformation which combine to alter the carbonyl oxygen of the lactone ring away from the putative active position.
(15) Accordingly, the concept that intravascular adenosine may exert some of its action on the capillary lumen was tested by coupling the agonists: N6-([aminoethylamino]carbonyl)methylphenyladenosine (ADAC) and N6-octylamine adenosine (NOA) to carboxylated latex microspheres (0.07 microns diameter); thus, insuring their intravascular confinement.
(16) Solubilities of [carbonyl-13C]triolein in phospholipid bilayer vesicles containing between 0 and 50 mol % free cholesterol, prepared by cosonication, were measured by 13C NMR.
(17) This paper reports the evaluation of five tetrahydro-beta-carboline carboxylic acids, formed from the interaction of woodsmoke carbonyls and tryptophan, for mutagenicity in the Ames test.
(18) Depletion of cells adhering to carbonyl iron led to higher ADCC activity.
(19) Similar was the cyclization which accompanied the basic hydrolysis of N-benzyl-oxycarbonyl-L-threonyl-L-phenylalanine methyl ester and of N-benzyloxy-carbonyl-L-seryl-DL-valine ethyl ester, and which resulted in the formation of L - O = C Thr-L-Phe and L - O = C Ser-DL-Val, respectively.
(20) In the binary complex with enzyme, the positions of the resonances of oxaloacetate are shifted relative to those of the free ligand as follows: C-1 (carboxylate), -2.5 ppm; C-2 (carbonyl), +4.3 ppm; C-3 (methylene), -0.6 ppm; C-4 (carboxylate), +1.3 ppm.
Quinone
Definition:
(n.) A crystalline substance, C6H4O2 (called also benzoketone), first obtained by the oxidation of quinic acid and regarded as a double ketone; also, by extension, any one of the series of which quinone proper is the type.
Example Sentences:
(1) The thiol-conjugating capacity of quinones may, however, be applied to reduce the tissue-damaging effects of stimulated neutrophils.
(2) The effect of dicoumarol on glucuronidation of 3-OH-benzo(a)pyrene (BP) appears to be due to inhibition of UDPglucuronosyltransferase (UDPGT) and not to an inhibited DT-diaphorase (NAD(P)H:quinone oxidoreductase); to date the only enzyme known to be inhibited by dicoumarol.
(3) The coupled dienone-phenol re-arrangement and keto-enol tautomerism of this quinone methide produce the observed 3,4-dihydroxybenzaldehyde.
(4) Moreover, it seems unlikely that quinones are involved directly (e.g.
(5) The second-order rate constants appear to be at least 3 orders of magnitude lower than the second-order constants for quenching of the fluorescent probes; this is taken as a clear indication that ubiquinone diffusion is not the rate-determining step in the quinone-enzyme interaction.
(6) 15 human tumour cell lines (lung, breast and colon) have been evaluated for their sensitivity to the quinone based anti-cancer drugs Mitomycin C, Porfiromycin, and EO9 (3-hydroxymethyl-5-aziridinyl-1-methyl-2-(IH-indole-4,7-dione)prop-beta- en-alpha-ol).
(7) These studies provide evidence that GHB exerts cytotoxicity specifically for cells that by their content of tyrosinase convert the phenol to the quinone.
(8) Comparison of these two activities for both the quinone and hydroquinone showed that the hydroquinone form had superior activities.
(9) Bis(alkylthio)quinones 4a-d and 5a-d, and corresponding hydroquinones 9b-d exhibited high activities both in vitro and in vivo.
(10) It seems that quinone pigments, especially 2-oxyjuglone, react with complex I faster than it follows from their approximate values of one-electron reduction potential calculated from their reactivities with flavocychrome b2 and adrenodoxin.
(11) Formation of catechol from quinone by cyst extracts was observed spectrophotometrically and chromatographically.
(12) The present studies were conducted to evaluate the relative effect of the parent chemical BHT and two of its major oxidative metabolites, 2,6-di-tert-butyl-4-hydroxymethylphenol (BHT-BzOH) and 2,6-di-tert-butyl-1,4-benzoquinone (BHT-quinone), on DMBA-induced rat mammary tumorigenesis and on the formation of rat mammary DMBA-DNA adducts in vivo.
(13) Quinones play a major role in allergic contact dermatitis caused by plants.
(14) The urushiol analogs 5-pentadecylresorcinol (PDR) and 3-heptadecylveratrole (HDV) which cannot form o-quinones were found to be ineffective sensitizers as well.
(15) Toxicity of quinone(di)imines to hepatocytes and CHO cells was not related to superoxide anion radical formation, and toxicity to CHO cells was not affected by exclusion of oxygen during exposure of the cells to the compounds.
(16) The activity of cytochrome P-450 reductase, which reduces quinones to hydroquinones in the estrogen redox cycle, was 6-fold higher in liver than in kidney of both control and estrogen-treated animals.
(17) The interaction of pyrroloquinoline quinone (PQQ) with amino groups was followed by measuring the capacity of adducts to reduce nitroblue tetrazolium (NBT).
(18) The menadione-induced quinone reductase was isolated from the cytoplasmic fraction of induced cells.
(19) 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].
(20) quinone complex (X) was chemically reduced (state [PIX-]; P is the reaction center bacteriochlorophyll dimer, I is the long wavelength bacteriopheophytin), and compares these with the fluorescence observed when all the traps are open (state [PIX]) and with the fluorescence observed when all the traps are closed (state [P+IX]).