Dose-specific production of chlorinated quinone and semiquinone adducts in rodent livers following administration of pentachlorophenol. (1/17)
Production of chlorinated quinoid metabolites was investigated in the livers of Sprague-Dawley rats and B6C3F1 mice following single oral administration of pentachlorophenol (PCP) (0-40 mg/kg body weight) and in male Fischer 344 rats, following chronic ingestion of PCP at 1,000 ppm in the diet for 6 months (equivalent to 60 mg PCP/kg body weight/day). Analyses of the rates of adduction in the livers of Sprague-Dawley rats and B6C3F1 mice suggested that the production of tetrachloro-1,2-benzosemiquinone (Cl4-1,2-SQ) adducts was proportionally greater at low doses of PCP (less than 4-10 mg/kg body weight) and was 40-fold greater in rats than in mice. Production of tetrachloro-1,4-benzoquinone (Cl4-1,4-BQ) adducts, on the other hand, was proportionally greater at high doses of PCP [greater than 60-230 mg/kg body weight] and was 2- to 11-fold greater in mice than in rats over the entire range of dosages. A mathematical model employed these data to predict the rates of daily adduct production and steady state levels of PCP-derived quinone and semiquinone adducts in rats and mice. To evaluate predictions of the model, levels of PCP-derived adducts at steady state were investigated in the livers of male Fischer 344 rats chronically ingesting 60 mg PCP/kg body weight/day. Levels of total Cl4-1,4-BQ-derived adducts in liver cytosolic proteins (Cp) (22.0 nmol/g) and in liver nuclear proteins (Np) (3.07 nmol/g) were comparable to those of model predictions (15.0 and 3.02 nmol/g for Cp and Np, respectively). Overall, these results suggest that species differences in the metabolism of PCP to semiquinones and quinones were, in part, responsible for the production of liver tumors in mice but not rats in chronic bioassays. (+info)Oxidative damage and direct adducts in calf thymus DNA induced by the pentachlorophenol metabolites, tetrachlorohydroquinone and tetrachloro-1,4-benzoquinone. (2/17)
DNA damage induced by quinoid metabolites of pentachlorophenol (PCP), i.e. tetrachloro-1,4-benzoquinone (Cl(4)BQ) and tetrachlorohydroquinone (Cl(4)HQ), was investigated in calf thymus DNA. The (32)P-post-labeling assay revealed four major and several minor adducts (3.5 adducts per 10(5) total nucleotides) that were produced in calf thymus DNA treated with Cl(4)BQ (5 mM). These DNA adducts were chemically stable even after conditions that induce thermal depurination and are unlikely to undergo depurination/depyrimidination to form apurinic/apyrimidinic (AP) sites. In addition, increases in 8-hydroxy-deoxyguanosine (8-HO-dG) (5 8-HO-dG per 10(5) nucleotides) and AP sites (0.5 AP sites per 10(5) nucleotides) were observed in Cl(4)BQ-modified calf thymus DNA. Further investigation indicated that in the presence of Cu(II) and NADPH, low concentrations of Cl(4)BQ (1 microM) induced a doubling of 8-HO-dG (10 8-HO-dG per 10(5) nucleotides) and dramatic increases in AP sites (20 AP sites per 10(5) nucleotides) and DNA single-strand breaks. The types of DNA damage induced by Cl(4)HQ plus Cu(II) were similar to those by Cl(4)BQ plus Cu(II) and NADPH, whereas catalase inhibited the formation of DNA damage. These data suggest that oxidative damage is causally involved in the formation of AP sites. Concentration-dependent increases in 8-HO-dG induced by Cl(4)HQ plus Cu(II) and Cl(4)BQ plus Cu(II) and NADPH were correlated with the formation of AP sites (r(2) = 0.977) with a ratio of 8-HO-dG to AP sites at 1:1.6. The AP site-cleavage assay confirmed that approximately 85% of the AP sites induced by Cl(4)HQ and Cu(II) were detected as 5'-cleaved AP sites. Since hydrogen peroxide alone causes similar DNA damage, these results suggest the involvement of Cu(II) and hydrogen peroxide in the induction of oxidative DNA damage by Cl(4)HQ/Cl(4)BQ. The data demonstrate that PCP quinone and hydroquinone induce direct and oxidative base modifications as well as the formation of 5'-cleaved AP sites in genomic DNA. These lesions may have important implications for PCP clastogenicity and carcinogenicity. (+info)Association of quinone-induced platelet anti-aggregation with cytotoxicity. (3/17)
Various anti-platelet drugs, including quinones, are being investigated as potential treatments for cardiovascular disease because of their ability to prevent excessive platelet aggregation. In the present investigation 3 naphthoquinones (2,3-dimethoxy-1,4-naphthoquinone [DMNQ], menadione, and 1,4-naphthoquinone [4-NQ]) were compared for their abilities to inhibit platelet aggregation, deplete glutathione (GSH) and protein thiols, and cause cytotoxicity. Platelet-rich plasma, isolated from Sprague-Dawley rats, was used for all experiments. The relative potency of the 3 quinones to inhibit platelet aggregation, deplete intracellular GSH and protein thiols, and cause cytotoxicity was 1,4-NQ > menadione >> DMNQ. Experiments using 2 thiol-modifying agents, dithiothreitol (DTT) and 1-chloro-2,4-dintrobenzene (CDNB), confirmed the key roles for GSH in quinone-induced platelet anti-aggregation and for protein thiols in quinone-induced cytotoxicity. Furthermore, the anti-aggregative effects of a group of 12 additional quinone derivatives were positively correlated with their ability to cause platelet cytotoxicity. Quinones that had a weak anti-aggregative effect did not induce cytotoxicity (measured as LDH leakage), whereas quinones that had a potent anti-aggregative effect resulted in significant LDH leakage (84-96%). In one instance, however, p-chloranil demonstrated a potent anti-aggregative effect, but did not induce significant LDH leakage. This can be explained by the inability of p-chloranil to deplete protein thiols, even though intracellular GSH levels decreased rapidly. These results suggest that quinones that deplete GSH in platelets demonstrate a marked anti-aggregative effect. If this anti-aggregative effect is subsequently followed by depletion of protein thiols, cytotoxicity results. (+info)Mechanistic appraisal of the charge-transfer complexes of promethazine with chloranil: a modelling approach. (4/17)
Various mechanisms are often used to explain the interaction between electron donors and acceptors. Commonly proposed mechanisms are those in which the acceptor interacts with the aromatic pi-systems in the donor molecule or the acceptor forms a weak interaction of the Lewis acid with Lewis base type. In this study, the above mechanisms were examined as well as other possible mechanisms. Promethazine was chosen as the model drug containing aromatic systems capable of pi-pi interaction as well as N-methyl group capable of forming a complex with the weak Lewis acid, p-chloranil. Our modelling studies revealed that the situation where the p-chloranil interacts with a protonated N-methyl group is the most significant mechanism of interaction, based on the calculated energies for the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), the Tripos force field energy terms and also the stability of the complexes during molecular dynamics simulations. (+info)A previously unrecognized step in pentachlorophenol degradation in Sphingobium chlorophenolicum is catalyzed by tetrachlorobenzoquinone reductase (PcpD). (5/17)
The first step in the pentachlorophenol (PCP) degradation pathway in Sphingobium chlorophenolicum has been believed for more than a decade to be conversion of PCP to tetrachlorohydroquinone. We show here that PCP is actually converted to tetrachlorobenzoquinone, which is subsequently reduced to tetrachlorohydroquinone by PcpD, a protein that had previously been suggested to be a PCP hydroxylase reductase. pcpD is immediately downstream of pcpB, the gene encoding PCP hydroxylase (PCP monooxygenase). Expression of PcpD is induced in the presence of PCP. A mutant strain lacking functional PcpD has an impaired ability to remove PCP from the medium. In contrast, the mutant strain removes tetrachlorophenol from the medium at the same rate as does the wild-type strain. These data suggest that PcpD catalyzes a step necessary for degradation of PCP, but not for degradation of tetrachlorophenol. Based upon the known mechanisms of flavin monooxygenases such as PCP hydroxylase, hydroxylation of PCP should produce tetrachlorobenzoquinone, while hydroxylation of tetrachlorophenol should produce tetrachlorohydroquinone. Thus, we proposed and verified experimentally that PcpD is a tetrachlorobenzoquinone reductase that catalyzes the NADPH-dependent reduction of tetrachlorobenzoquinone to tetrachlorohydroquinone. (+info)Simultaneous spectrophotometric determination of p-benzoquinone and chloranil after microcrystalline naphthalene extraction by using genetic algorithm-based wavelength selection-partial least squares regression. (6/17)
Microcrystalline naphthalene extraction has been used for the preconcentration of p-benzoquinone and tetrachloro-p-benzoquinone (chloranil), after their reaction by aniline, and later simultaneous spectrophotometric analysis by genetic algorithm-partial least squares (GA-PLS) calibration. The chemical variables affecting the analytical performance of the methodology were studied and optimized. Under the optimum conditions i.e., [aniline] = 0.05 M and [naphthalene] = 2.2% (w/v), preconcentration of 25 ml of sample solution permitted the detection of 0.32 and 0.23 microg ml(-1) for p-benzoquinone and chloranil, respectively. The predictive abilities of partial least squares regression (PLS) and genetic algorithm-partial least squares regression (GA-PLS) were examined for simultaneous determination of two quinones. The GA-PLS shows superiority over other PLS methods due to the wavelength selection in PLS calibration using a genetic algorithm without loss of prediction capacity, provides useful information about the chemical system. (+info)Oxidative dimer produced from a 2,3,4-trihydroxybenzoic ester. (7/17)
The DPPH radical-scavenging abilities of the naturally occurring phenolic acid, 2,3,4-trihydroxybenzoic acid, and its methyl ester were evaluated. Both compounds in acetonitrile scavenged as many as four radicals compared to three or fewer radical consumption in acetone or ethanol. Only the ester showed relatively high ability in methanol. Oxidation with o-chloranil in acetonitrile resulted in methyl 2,3,4-trihydroxybenzoate giving a novel benzocoumarin-type dimer, its chemical structure being confirmed by spectroscopic evidence. The formation of this dimer might partly account for the higher radical-scavenging efficiency of the ester in acetonitrile or methanol. (+info)Flow-injection spectrophotometric determination of azithromycin in pharmaceutical formulations using p-chloranil in the presence of hydrogen peroxide. (8/17)
A flow-injection (FI) spectrophotometric procedure exploiting merging zones is proposed for the determination of azithromycin in pharmaceutical formulations. The method is based on the reaction of azithromycin with tetrachloro-p-benzoquinone (p-chloranil) accelerated by hydrogen peroxide and conducted in a methanol medium, producing a purple-red color compound (lambda(max) = 540 nm). The FI system and the experimental conditions were optimized using a multivariate method. Beer's law is obeyed in a concentration range of 50 - 1600 microg mL(-1) with an excellent correlation coefficient (r = 0.9998). The detection limit and the quantification limit were 6.6 and 22.1 microg mL(-1), respectively. No interference was observed from the common excipients, and the recoveries were within 98.6 to 100.4%. The procedure was applied to the determination of azithromycin in pharmaceuticals with a high sampling rate (65 samples h(-1)). The results obtained by the proposed method were in good agreement with those obtained by the comparative method at 95% confidence level. (+info)
Chloranil
Like the parent benzoquinone, chloranil is a planar molecule that functions as a mild oxidant. Chloranil is produced by ... Chloranil is used to test for free secondary amines. This test is useful for checking for the presence of proline derivatives. ... Chloranil is a quinone with the molecular formula C6Cl4O2. Also known as tetrachloro-1,4-benzoquinone, it is a yellow solid. ... Chloranilic acid 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) Chloranil at Sigma-Aldrich J.-M. Lü, S. V. Rosokha, I. S. ...
Chloranilic acid
Chloranil "Chloranilic acid". Sigma-Aldrich. Andersen, E. K. (1967). "The Crystal and Molecular Structure of Hydroxyquinones ... The compound is obtained by hydrolysis of chloranil: C6Cl4O2 + 2 H2O → C6Cl2O2(OH)2 + 2 HCl It is centrosymmetric, planar ...
Hexachlorocyclohexa-2,5-dien-1-one
The hydrolysis of HCP gives chloranil. "SAFETY DATA SHEET". ThermoFisher Scientific. 18 December 2020. S. Gali, C. Miravitlles ...
2,3-Dichloro-5,6-dicyano-1,4-benzoquinone
Synthesis of DDQ involves cyanation of chloranil. J. Thiele and F. Günther first reported a 6-step preparation in 1906. The ...
Aniline
Hydrochloric acid and potassium chlorate give chloranil. Potassium permanganate in neutral solution oxidizes it to nitrobenzene ...
Mesitylene)molybdenum tricarbonyl
The Molybdenum complex is activated with an oxidant such as chloranil. The result of the charge transfer facilitates ring ...
1,4-Benzoquinone
Chloranil 1,4-C6Cl4O2 is another potent oxidant and dehydrogenation agent. Monochloro-p-benzoquinone is yet another but milder ...
Pigment violet 23
It is prepared by condensation of chloranil and 3-amino-N-ethylcarbazole. It has a centrosymmetric angular structure. For many ... Pigment violet 23 is prepared by condensation of an aniline with chloranil. Chamberlain, Terence "Dioxazine violet pigments" ...
Hidden states of matter
"Photoinduced valence instability in the organic molecular compound tetrathiafulvalene-p-chloranil (TTF-CA)". Physical Review B ... "Photoinduced phase transition in tetrathiafulvalene-p-chloranil observed in femtosecond reflection spectroscopy". Physical ...
James B. Conant
I. The Use of the Chloranil Electrode in Glacial Acetic Acid and the Strength of Certain Weak Bases". Journal of the American ...
2,2'-Dipyrromethene
The dipyrromethane core is then oxidized to dipyrromethene using a quinone oxidant such as DDQ or p-chloranil. Alternatively, ...
Mibolerone
In the case at hand, heating acetate (1) with chloranil gives the conjugated dienone (2), and reaction of that compound with ... Chloranil (tetrachloroquinone) is the forerunner of dichlorodicyanoquinone (DDQ), a reagent used extensively for introducing ...
Corrole
The open-ring product, a bilane (or tetrapyrrane), is cyclized by oxidation, typically with p-chloranil: Corrole and porphyrins ...
Quinone
Chloranil, a reagent in organic chemistry Lawsone, a dye present in the leaves of the henna plant Alizarin, a common red dye ... Relative to benzoquinone, more strongly oxidizing quinones include chloranil and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone ( ...
Melengestrol
6-diene with chloranil (11). Acetylation under forcing conditions completes the synthesis of melengesterol acetate. ...
Medrogestone
... as well as chloranil in a single reaction; the 4,6-diene, (medrogesterone), is obtained directly from this step. Medrogestone ...
Heptacene
... organic oxidation with P-chloranil in toluene 2 hours reflux and 81% yield c] Bishydroxylation with N-Methylmorpholine N-oxide ...
List of MeSH codes (D02)
... chloranil MeSH D02.806.250.280 - dibromothymoquinone MeSH D02.806.250.700 - plastoquinone MeSH D02.806.250.900 - ubiquinone ...
Cyproterone acetate
The following is one such synthesis: The dehydrogenation of 17α-hydroxyprogesterone acetate [302-23-8] (1) with chloranil ( ...
BODIPY
... which is oxidized to dipyrromethene using a quinone oxidant such as DDQ or p-chloranil. Alternatively, dipyrromethenes are ...
Organovanadium chemistry
... chloranil → VO(mes)3 VOCl3 + ZnPh2 → VOPhCl2 + "ZnPh(Cl)" Well-defined vanadium compounds do not appear as catalysts in any ...
Ponceau S
... charge-transfer complexes of Ponceau S with p-chloranil, chloranilic and picric acids". Research on Chemical Intermediates. 41 ...
List of fungicides
... fungicides carbendazim carboxin carpropamid carvone Cheshunt mixture chinomethionat chlobenthiazone chloraniformethan chloranil ...
Azulene
DMF Luche reduction to alcohol with sodium borohydride elimination reaction with Burgess reagent oxidation with p-chloranil ...
CHLORANIL | C6Cl4O2 | ChemSpider
Determination of individual proton affinities of reserpine from its UV-vis and charge-transfer spectra - PubMed
Publication Detail
BAT BEP Guidelines Article 5
TEXTILE AND LEATHER DYEING (WITH CHLORANIL) AND FINISHING (WITH ALKALINE EXTRACTION). VI.K. SHREDDER PLANTS FOR THE TREATMENT ... TEXTILE AND LEATHER DYEING (WITH CHLORANIL) AND FINISHING (WITH ALKALINE EXTRACTION). VI.K. SHREDDER PLANTS FOR THE TREATMENT ... TEXTILE AND LEATHER DYEING (WITH CHLORANIL) AND FINISHING (WITH ALKALINE EXTRACTION). VI.K. SHREDDER PLANTS FOR THE TREATMENT ...
Graduate Thesis Or Dissertation | The chemistry of certain tetrahydropyrimidines | ID: 5h73pz74c | ScholarsArchive@OSU
MeSH Browser
Chloranil Preferred Term Term UI T007832. Date01/01/1999. LexicalTag NON. ThesaurusID ... Chloranil Preferred Concept UI. M0004130. Registry Number. 01W5X7N5XV. Related Numbers. 118-75-2. Scope Note. A quinone ... Chloranil. Tree Number(s). D02.806.250.210. Unique ID. D002703. RDF Unique Identifier. http://id.nlm.nih.gov/mesh/D002703 Scope ...
Identification of Activators of Human Fumarate Hydratase by Quantitative High-Throughput Screening - PubMed
Biomarkers Search
HeteroCycles
CAS 58794-09-5 7-Bromoisoquinoline products price,suppliers
MeSH Browser
Chloranil Preferred Term Term UI T007832. Date01/01/1999. LexicalTag NON. ThesaurusID ... Chloranil Preferred Concept UI. M0004130. Registry Number. 01W5X7N5XV. Related Numbers. 118-75-2. Scope Note. A quinone ... Chloranil. Tree Number(s). D02.806.250.210. Unique ID. D002703. RDF Unique Identifier. http://id.nlm.nih.gov/mesh/D002703 Scope ...
noun|ic$|adj|2013|ORG RULE|SELF
Dijana Žilić - Institut Ruđer Bošković
DeCS
Quinoxalinas
E0000163|Adriamycin|doxorubicin
Glutathione. Medical search. Definitions
Dyes Intermediates Manufacturer, Dyes Intermediates Supplier, Exporter In Mumbai
NDF-RT Code NDF-RT Name
High Quality 99% Loliolide Manufacturer - Dideu
2012
Mesitylene)molybdenum tricarbonyl - Alchetron, the free social encyclopedia
BROMLY - First Name BROMLY and rhyming word and other names with BROMLY
Pigment fjólublátt 23-Corimax Violet RLS - Zeya Chemicals
Pigment violet 23 is prepared by condensation of an aniline with chloranil.[From Wiki]. Tæknilegar breytur Pigment violet 23. ... It is prepared by condensation of chloranil and 3-amino-N-ethylcarbazole. It has a centrosymmetric angular structure. For many ... Chloranil) er látin þéttast og loka efnahvörfum, síað, þvegið með vatni og þurrkað til að fá hráan karbazól fjólublátt; að ...
DeCS 2017 - December 21, 2017 version
ON THE ELECTRON-DONATING PROPERTIES OF INDOLES
Acervo Digital: Desenvolvimento de métodos para determinação de sulfonamidas, dipirona e citrato de sildenafil em matrizes...
ABORTIFACIENT AGENTS ABORTIFACIENT AGENTS
AND PE CHLORANIL ENVIRONMENTAL POLLUTANTS, NOXAE, AND PE CHLORDAN ENVIRONMENTAL POLLUTANTS, NOXAE, AND PE CHLORDECONE ... INDUSTRIAL CHLORANIL FUNGICIDES, INDUSTRIAL DINITROPHENOLS FUNGICIDES, INDUSTRIAL ETHYLMERCURIC CHLORIDE FUNGICIDES, INDUSTRIAL ... PESTICIDES CHLORANIL PESTICIDES CHLORDAN PESTICIDES CHLORDECONE PESTICIDES CHLORFENVINPHOS PESTICIDES CHLORPHENAMIDINE ...
BENZOQUINONE2
- 16. The acute exposure of tetrachloro-p-benzoquinone (a.k.a. chloranil) triggers inflammation and neurological dysfunction via Toll-like receptor 4 signaling: The protective role of melatonin preconditioning. (nih.gov)
- That this is the case was shown experimentally by E. Fujimori,t who measured the charge transfer spectrum of indole with various classical acceptors, capable of a-x interaction, like tri- nitrobenzene, benzoquinone, chloranil, and bromanil. (nih.gov)
Reaction2
- Each product was dissolved in benzene (5 mL), o-chloranil (1.0 eq.) was added, and each reaction mixture was refluxed for 5 h. (guidechem.com)
- The method involved the reaction between sildenafil citrate and tetrachlorobenzoquinone (p-chloranil), accelerated by the addition of H2O2 producing a stable colored complex (λ = 535 nm). (unesp.br)
Addition1
- The results obtained were further checked by noting the variation of fluorescence intensity of reserpine upon addition of o-chloranil, acid, and base, and almost complete agreement with the absorption spectrometric result was observed. (nih.gov)
Studies1
- The possibility that proteins can be so converted from insulators into conductors has been demonstrated by Eley and coworkers (5, 6) in conduction studies on complexes of bovine plasma albumin with chloranil or chlorophyll, and our own studies (7-9) indicate the possibility that aldehydes such as methylglyoxal can act as electron acceptors in charge-transfer interactions with proteins. (nih.gov)