Chloranil: A quinone fungicide used for treatment of seeds and foliage.HydroquinonesChlorine: A greenish-yellow, diatomic gas that is a member of the halogen family of elements. It has the atomic symbol Cl, atomic number 17, and atomic weight 70.906. It is a powerful irritant that can cause fatal pulmonary edema. Chlorine is used in manufacturing, as a reagent in synthetic chemistry, for water purification, and in the production of chlorinated lime, which is used in fabric bleaching.Hydrochloric Acid: A strong corrosive acid that is commonly used as a laboratory reagent. It is formed by dissolving hydrogen chloride in water. GASTRIC ACID is the hydrochloric acid component of GASTRIC JUICE.Chlorine Compounds: Inorganic compounds that contain chlorine as an integral part of the molecule.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Space-Time Clustering: A statistically significant excess of cases of a disease, occurring within a limited space-time continuum.Gases: The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Silicates: The generic term for salts derived from silica or the silicic acids. They contain silicon, oxygen, and one or more metals, and may contain hydrogen. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th Ed)Lewis Acids: Any chemical species which accepts an electron-pair from a LEWIS BASE in a chemical bonding reaction.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Silicon: A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].Organosilicon Compounds: Organic compounds that contain silicon as an integral part of the molecule.Silicon Compounds: Inorganic compounds that contain silicon as an integral part of the molecule.Magnesium Silicates: A generic term for a variety of compounds that contain silicon, oxygen, and magnesium, and may contain hydrogen. Examples include TALC and some kinds of ASBESTOS.Porphyrins: A group of compounds containing the porphin structure, four pyrrole rings connected by methine bridges in a cyclic configuration to which a variety of side chains are attached. The nature of the side chain is indicated by a prefix, as uroporphyrin, hematoporphyrin, etc. The porphyrins, in combination with iron, form the heme component in biologically significant compounds such as hemoglobin and myoglobin.PorphobilinogenMacrocyclic Compounds: Cyclic compounds with a ring size of approximately 1-4 dozen atoms.Solvents: Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)Hydroxymethylbilane Synthase: An enzyme that catalyzes the tetrapolymerization of the monopyrrole PORPHOBILINOGEN into the hydroxymethylbilane preuroporphyrinogen (UROPORPHYRINOGENS) in several discrete steps. It is the third enzyme in the 8-enzyme biosynthetic pathway of HEME. In humans, deficiency in this enzyme encoded by HMBS (or PBGD) gene results in a form of neurological porphyria (PORPHYRIA, ACUTE INTERMITTENT). This enzyme was formerly listed as EC 4.3.1.8Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Pressure: A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Adhesives: Substances that cause the adherence of two surfaces. They include glues (properly collagen-derived adhesives), mucilages, sticky pastes, gums, resins, or latex.Transducers, Pressure: Transducers that are activated by pressure changes, e.g., blood pressure.Hydrostatic Pressure: The pressure due to the weight of fluid.PaintAdministration, Cutaneous: The application of suitable drug dosage forms to the skin for either local or systemic effects.Aniline CompoundsAniline Hydroxylase: A drug-metabolizing, cytochrome P-450 enzyme which catalyzes the hydroxylation of aniline to hydroxyaniline in the presence of reduced flavoprotein and molecular oxygen. EC 1.14.14.-.Terminology as Topic: The terms, expressions, designations, or symbols used in a particular science, discipline, or specialized subject area.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.Chemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.Streptomyces: A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.Fermentation: Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.Fungicides, Industrial: Chemicals that kill or inhibit the growth of fungi in agricultural applications, on wood, plastics, or other materials, in swimming pools, etc.Insecticides: Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.SemicarbazonesPyridines: Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.Halogens: A family of nonmetallic, generally electronegative, elements that form group 17 (formerly group VIIa) of the periodic table.Alkynes: Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.Plant Growth Regulators: Any of the hormones produced naturally in plants and active in controlling growth and other functions. There are three primary classes: auxins, cytokinins, and gibberellins.Polarography: An electrochemical technique for measuring the current that flows in solution as a function of an applied voltage. The observed polarographic wave, resulting from the electrochemical response, depends on the way voltage is applied (linear sweep or differential pulse) and the type of electrode used. Usually a mercury drop electrode is used.Quaternary Ammonium Compounds: Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)NitrobenzenesElectrolytes: Substances that dissociate into two or more ions, to some extent, in water. Solutions of electrolytes thus conduct an electric current and can be decomposed by it (ELECTROLYSIS). (Grant & Hackh's Chemical Dictionary, 5th ed)Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Solutions: The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Staphylococcus aureus: Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Access to Information: Individual's rights to obtain and use information collected or generated by others.Journal Impact Factor: A quantitative measure of the frequency on average with which articles in a journal have been cited in a given period of time.Bibliometrics: The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Peer Review, Research: The evaluation by experts of the quality and pertinence of research or research proposals of other experts in the same field. Peer review is used by editors in deciding which submissions warrant publication, by granting agencies to determine which proposals should be funded, and by academic institutions in tenure decisions.

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)

Looking for chloranil? Find out information about chloranil. C6Cl4O2 Yellow leaflets melting at 290°C; soluble in organic solvents; made from phenol by treatment with potassium chloride and hydrochloric acid; used as... Explanation of chloranil
Pentachlorophenol (PCP), a xenobiocide used to preserve lumbers, is a major environmental pollutant in North America. In spite of an expected high resistance to biodegradation, a number of aquatic and soil bacteria can degrade PCP. In this study, we cloned, expressed and purified tetrachlorobenzoquinone reductase (PcpD), the second enzyme in the PCP biodegradation pathway in Sphingobium chlorophenolicum. PcpD, present mainly as a homo-trimer, exhibited low but statistically significant activity in the reduction of tetrachlorobenzoquinone to tetrachlorohydroquinone. The optimal pH for PcpD activity was 7.0. PcpD was stimulated by tetrachlorohydroquinone at low concentrations but inhibited at high concentrations. Because of the constitutive expression and relatively high catalytic efficiency of downstream enzyme tetrachlorohydroquinone reductive dehalogenase, tetrachlorohydroquinone was unlikely to accumulate in high concentrations, suggesting that PcpD would only be stimulated by tetrachlorohydroquinone
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A sensor electrode to detect one or more components in a liquid mixture comprises an electrically conductive material having at least an an external surface, the combination of an enzyme catalytic for a reaction of the desired component, and a mediator compound which transfers electrons from the enzyme to the electrode when such catalytic activity takes place. It can be used as an in vivo glucose sensor either with a silver electrode coated with e.g. glucose oxidase and a polyviologen as the mediators, or with a particulate carbon electrode, glucose oxidase and chloranil or fluoranil as mediator. Another system is to use bacterial glucose dehydrogenase or glucose oxidase as the enzyme and/or ferrocene or a ferrocene derivative as the mediators compound to give electrodes with improved linearity, speed of response and insensitivity to oxygen.
BENZOYL CHLORIDE, CHLOROSOLPHONIC ACID PURE, CALCIUM HYPOPHOSPHITE, CHLORAL [TRICHLOROACETALDEHYDE], CHLORANIL, ETHER ANHYDROUS, GUM ACACIA, GUM ARABIC, GUM GUAR POWDER, HYPOPHOSPHORUS ACID, ISATOIC ANHYDRIDE, ISOBUTYLENE, LEAD SUB - ACETATE, MERCURY NITRATE, MERCURY CHLORIDE, METHYL TERTBUTYL ETHER, MAGNESIUM HYPOPHOSPHITE, p - NITROBENZOIC ACID METHYL ESTER, p - NITROMETHYLBENZOATE, POLY ALUMINIUM CHLORIDE, POTASH ALUM, POTASSIUM BICARBONATE, POTASSIUM HYDROXIDE PELLETS, PYROPHOSPHORYL CHLORIDE, SODIUM HYDROXIDE PELLETS, STANNOUS CHLORIDE, STANNIC CHLORIDE, TETRAPOTASSIUM PYROPHOSPHATE, TRICHLOROACETIC ACID, TRICLOSAN, TRIMETHYL CHLOROSILANE
The major glutathione S-transferase isoenzyme from bovine brain was isolated and purified approx. 500-fold. The enzyme has a pI of 7.39 +/- 0.02 and consists of two non-identical subunits having apparent Mr values of 22,000 and 24,000. The enzyme is uniformly distributed in brain, and kinetic data at pH 6.5 with 1-chloro-2,4-dinitrobenzene (CDNB) as substrate suggest a random rapid-equilibrium mechanism. The kinetics of inhibition by product, by GSH analogues and by NADH are consistent with the suggested mechanism and require inhibitor binding to several different enzyme forms. Long-chain fatty acids are excellent inhibitors of the enzyme, and values of 1nKi for hexanoic acid, octanoic acid, decanoic acid and lauric acid form a linear series when plotted as a function of alkyl chain length. A free-energy change of -1900 J/mol (-455 cal/mol) per CH2 unit is calculated for the contribution of hydrophobic binding energy to the inhibition constants. The turnover number of the purified enzyme dimer ...
16669-42-4 - OJTHLNYBRBMCBW-UHFFFAOYSA-N - Phenol, 4,4-(1-methylethylidene)bis(2,3,5,6-tetrachloro- - Similar structures search, synonyms, formulas, resource links, and other chemical information.
56815-78-2 - UMOZFNODOJXMKD-UHFFFAOYSA-J - Platinum (IV), bis(cyclopentylammine)tetrachloro-, cis- - Similar structures search, synonyms, formulas, resource links, and other chemical information.
2,3,5,6-Tetrachloro-4-nitroanisole, an agricultural fungicide and acaricide, was selected for bioassay by the National Cancer Institute because of its structural similarity to pentachloronitrobenzene, a pesticide classified as tumorigenic by the Secretarys Commission on Pesticides and their Relationship to Environmental Health.. A bioassay for possible carcinogenicity of 2,4,5,6-tetrachloro-4-nitroanisole was conducted using Fischer 344 rats and B6C3F1 mice. 2,3,5,6-Tetrachloro-4-nitroanisole was administered in the feed, at either of two concentrations, to groups of male and female animals of each species. The high and low dietary concentrations used in the chronic bioassay were 0.012 and 0.006 percent, respectively, for both species. After a 104-week period of chemical administration, observation of rats continued for up to 3 weeks and observation of mice continued for up to 1 week. For rats 50 animals of each sex were placed on test as controls, while for mice 55 animals of each sex were ...
Vibrational spectra of CT complexes of acridine orange. Sagar Agravat, Vishal Jain & A T Oza*. Received 4 May 2007; revised 31 January 2008. Infrared spectra of acridine orange and its charge transfer complexes with acceptors such as chloranil, 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), 7,7,8,8-tetracyano-p-quinodimethane (TCNQ) and tetracyano-p-ethylene (TCNE) are reported here. Their photo conducting nature is explained with two absorption edges in infrared range associated with non-equivalent sites of chloride ion or formation of bonding, non-bonding and antibonding orbitals. The mid-IR transition is usually direct and the low-energy transition is indirect. Whether the transition is allowed or forbidden depends on average intermolecular distance. This differs from ordinary ternary complexes in which two acceptors give rise to two conduction bands. Also, there is absence of any screening found in two donor based ternary systems. There is some band tailing of phonon bands in absorption ...
2,4,6-Trihydroxybenzoic acid Extract 83-30-7 Suppliers,provide 2,4,6-Trihydroxybenzoic acid Extract 83-30-7 product and the products related with China (Mainland) 2,4,6-Trihydroxybenzoic acid Extract 83-30-7 Baoji Guokang Healthchem co.,ltd China (Mainland)
Although previous studies have addressed the consequences of treating cells (5) or nucleosides (7) with TCBQ, the rates of physiologically relevant reactions between TCBQ and nucleophiles have not been examined. TCBQ reacts with thiols with rate constants ,1.4 × 106-1.3 × 107 M−1⋅s−1 at pH 7. The apparent decrease in reactivity going from cysteine to glutathione to β-ME correlates with their pKas (8.2, 9.2, and 9.6, respectively) (Fig. S1) and is consistent with the reactive moiety being the thiolate. Given these pKa values, 6%, 0.6%, and 0.3% of the thiols will be deprotonated at pH 7 for cysteine, glutathione, and β-ME, respectively. Thus, the rate constant for reaction between TCBQ and thiolates is ,108 M−1⋅s−1 , essentially the diffusion-controlled limit. It is important to note that each molecule of TCBQ can react with multiple thiols, leading to depletion of up to four molecules of glutathione per TCBQ (23). Further, reaction of TCBQ with multiple thiols can lead to ...
Product Details of P-Benzoquinone CAS 106-51-4 Benzoquinone p-Benzoquinone P-quinone PBQ Quinone, P-Benzoquinone CAS 106-51-4 Benzoquinone p-Benzoquinone P-quinone PBQ Quinone from China manufacturer on Hisupplier.com.
TY - JOUR. T1 - Poly-vinylidene-fluoride/p-benzoquinone gel polymer electrolyte with good performance by redox mediator effect for Li-Air battery. AU - Kim, Young Bok. AU - Kim, Il To. AU - Song, Myeong Jun. AU - Shin, Moo Whan. PY - 2016/8/20. Y1 - 2016/8/20. N2 - In this study, the poly-vinylidene fluoride (PVDF)/p-benzoquinone (pBQ) gel polymer electrolyte (GPE) is synthesized well with LiTFSI/TEGDME for Li-Air battery (LAB) applications. The PVDF/pBQ GPEs are characterized by electrochemical analysis and compared to the PVDF GPE. We confirm that pBQ molecule in PVDF GPE shows redox mediate behavior during charge-discharge process. Employing PVDF/pBQ GPE for LAB leads to an improved cycleability from 2 to over 30. In addition it results in a charge voltage decrease from around 4.2 V to around 3.3 V. The energy cycle efficiency (ECE) is improved about 15%. The pBQ accelerates to the formation of an amorphous phase on synthesized PVDF GPE matrix by acting inhibitor for polymerization. It leads ...
Free radical-triggered tissue damage is believed to play an essential role in a variety of human diseases. Pentachlorophenol (PCP) is applied as a pesticide worldwide in both industries and homes. It is used extensively as a biocide and wood preservative. Tetrachlorohydroquinone (TCHQ) was proved as a major toxic metabolite of PCP, contributing the release of free radicals during PCP metabolism. PCP has been proposed as a tumor promoter; however, only limited knowledge is available regarding the mechanisms of tumor promotion induced by PCP and its metabolite, TCHQ. A growing amount of literature suggests that a link between reactive oxygen species (ROS) and tumor promotion could exist. Herein, we summarize the findings regarding the ROS-triggered signaling pathways involved in the cytotoxicity and tumor promotion effects of PCP and TCHQ. Some of the notable findings demonstrated that TCHQ can induce DNA lesions and glutathione depletion in mammalian cells; meanwhile, oxidative stress and apoptosis
Machine fault prognosis techniques have been considered profoundly in the recent time due to their profit for reducing unexpected faults or unscheduled maintenance. With those techniques, the working conditions of components, the trending of fault propagation, and the time-to-failure are forecasted precisely before they reach the failure thresholds. In this work, we propose an approach of Least Square Regression Tree (LSRT), which is an extension of the Classification and Regression Tree (CART), in association with one-step-ahead prediction of time-series forecasting technique to predict the future conditions of machines. In this technique, the number of available observations is firstly determined by using Caos method and LSRT is employed as prognosis system in the next step. The proposed approach is evaluated by real data of low methane compressor. Furthermore, the comparison between the predicted results ...
1,4-Benzoquinone 常見於的活性的結構分子中,亦被廣泛地運用在藥物結構修飾。 在化學反應上,1,4-benzoquinone 較常進行的是親核基取代反應,藉由這一類的反應能 導入不同的基團,經常能提升化合物的生物活性。然而,此類的親核基取代反應對於 取代在 C2或 C3位置,並無太大的選擇性。為了提高化學選擇性、清楚了解取代基位 置對於生物活性的影響,本計畫將以兩類具 1,4-benzoquinone結構的 quinoline-5,8-dione 及天然物 denbinobin 作為探討對象,利用離去基導向、溫度控制及路易士酸輔助等方 法,提高親核基取代反應的位向選擇性,合成一系列的 2-aroyl-quinoline-5,8-dione 及 denbinobin 衍生物,初步的實驗數據顯示 2-aroyl-quinoline-5,8-dione 及 denbinobin 衍生 物接具有良好的癌細胞生長抑制效果,因此本計畫將持續探討不同取代基對於活性的 影響,同時計畫合成各式 ...
View Notes - 10.2 from STAT 131 at Berkeley. Inferenceforregression Analysisofvarianceforregression Bivariatenormaldistribution Simplelinearregressionmodel Simplelinearregressionmodel Least squares
For a set of data, the total variation or sum of squares for y is SST - 143.0 and the error sum of squares is SSE = 24.0. What proportion of the variation in y is explained by the regression equation? 2. A. Determine the.
Creative-Proteomics offer cas 106-51-4 1,4-BENZOQUINONE (D4, 98%). We are specialized in manufacturing Stabel Isotope Labeled Analytical Standard products.
4. students should know that the pictures were faked: This goes without saying. Since biologists have known since the 1980s that peppered moths do not normally rest on tree trunks, not to tell students that the pictures were staged (in many cases by gluing or pinning dead moths to desired backgrounds) constitutes as clear a case of scientific fraud as any on record. Yet Im aware of no sincere efforts by Darwinists to inform students of this -- despite their pious declarations of good intentions. Almost all recent (1998-2000) biology textbooks use such photos without any indication that they were staged. As a scientist, I find this absolutely inexcusable. If dogmatic Darwinists were as smart as they pretend to be, they would be actively campaigning -- for their own good! -- to rid textbooks of this fraud. Acquiescence in scientific misconduct will not look good on their resumes ...
Pentachlorophenol (PCP) is a widely used and highly toxic wood preservative. It was first introduced as a pesticide in 1936 (7) and is not known to be a natural product. Despite its recent introduction into the environment and its high toxicity, several strains of Sphingobium chlorophenolicum (previously Sphingomonas chlorophenolica) (24) that can mineralize PCP have been identified. The best studied of these are strains ATCC 39723 (19), RA-2 (23), and UG30 (6). It appears that S. chlorophenolicum has assembled a new metabolic pathway capable of converting this anthropogenic compound into a recognizable metabolite. Our previous studies suggest that this pathway has been assembled by patching together enzymes from at least two different metabolic pathways (8). PCP hydroxylase (PCP monooxygenase; EC 1.14.13.50) and 2,6-dichlorohydroquinone dioxygenase may have originated from enzymes that hydroxylated a naturally occurring chlorinated phenol and then cleaved the resulting hydroquinone. ...
Using cyclic voltammetry, the electrochemistry of aqueous solutions of 4-methoxy-1,2-benzoquinone was investigated over the pH range 0-8. From the variation of half-wave potential with pH, it was inferred that the quinone was reduced to the hydroquinone; no acid-base reactions involving either the quinone or hydroquinone were observed. At low pH ( , 3), the cyclic voltammogram of the benzoquinone changed rapidly to a second pair of peaks at lower potentials. These were shown to be due to 2-hydroxy-1,4-benzoquinone, formed by hydrolysis of the original compound. The other hydrolysis product, methanol, was detected chromatographically. The hydrolysis reaction was shown to be first order both with respect to the 1,2-benzoquinone and protons. At pH 6 and above, 4-methoxy-1,2-benzoquinone showed a second type of decomposition whose rate was approximately first order in hydroxide ion. Using electrochemical and spectroscopic measurements, it was also demonstrated that 4-methoxy-1,2-benzoquinone was ...
Looking for online definition of 1,4-benzoquinone in the Medical Dictionary? 1,4-benzoquinone explanation free. What is 1,4-benzoquinone? Meaning of 1,4-benzoquinone medical term. What does 1,4-benzoquinone mean?
I found nothing on any possible reaction between acetone and p-benzoquinone with SciFinder. If there would be a reaction under basic conditions, I would guess that 5-hydroxy-2-methylbenzofurane would be the expected product. I would guess the reason why this apparently does not happen is because benzoquinone is unlikely to be stable toward the strong bases required for the enolization of acetone (such as hydroxides which can react with quinones themselves ...
Robert P. Hayes, Abigail R. Green, Mark S. Nissen, Kevin M. Lewis, Luying Xun and ChulHee Kang Structural characterization of 2,6-dichloro-p-hydroquinone 1,2-dioxygenase (PcpA) from Sphingobium chlorophenolicum, a new type of aromatic ring-cleavage enzyme Molecular Microbiology 88. Version of Record online: 26 MAR 2013 , DOI: 10.1111/mmi.12204. Complete the form below and we will send an e-mail message containing a link to the selected article on your behalf. Required = Required Field. ...
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Provides (weighted) Partial least squares Regression for generalized linear models and repeated k-fold cross-validation of such models using various criteria. It allows for missing data in the explanatory variables. Bootstrap confidence intervals constructions are also available.
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Pentachlorophenol (PCP) is a group of polychlorinated compounds used as preservatives for wood, leather and textiles to shield against the attack of moulds, fungus and bacteria.
Pentachlorophenol is a chlorinated hydrocarbon fungicide and insecticide. It is primarily used to protect timber from wood boring insects and fungal rot.
BackgroundThe objective of the present study was to test the ability of the partial least squares regression technique to impute genotypes from low density single nucleotide polymorphisms (SNP) panels i.e. 3K or 7K to a high density panel with 50K SNP. No pedigree information was used.MethodsData consisted of 2093 Holstein, 749 Brown Swiss and 479 Simmental bulls genotyped with the Illumina 50K Beadchip. First, a single-breed approach was applied by using only data from Holstein animals. Then, to enlarge the training population, data from the three breeds were combined and a multi-breed analysis was performed. Accuracies of genotypes imputed using the partial least squares regression method were compared with those obtained by using the Beagle software. The impact of genotype imputation on breeding value prediction was evaluated for milk yield, fat content and protein content.ResultsIn the single-breed approach, the accuracy of imputation using partial least squares regression was around 90 and 94% for
TY - JOUR. T1 - Synthesis and antiviral evaluation of polyhalogenated imidazole nucleosides. T2 - Dimensional analogues of 2,5,6-trichloro-1-(β-D-ribofuranosyl) benzimidazole. AU - Chien, Tun Cheng. AU - Saluja, Sunita S.. AU - Drach, John C.. AU - Townsend, Leroy B.. PY - 2004/11/4. Y1 - 2004/11/4. N2 - A series of polyhalogenated imidazole nucleosides were designed and synthesized as ring-contracted analogues of 2,5,6-trichloro-1-(β-D- ribofuranosyl)benzimidazole (TCRB) and its 2-bromo analogue (BDCRB) in an effort to explore the spatial limitation of the active pocket(s) in the target protein(s). 2,4,5-Trichloro-, 2-bromo-4,5-dichloro-, and 2,4,5-tribromoimidazole nucleosides were prepared by a condensation of the preformed heterocycles with the appropriate sugar precursors. The ribofuranosyl and xylofuranosyl analogues were prepared by a direct glycosylation using the Vorbruggens silylation method and provided exclusively the β-anomers. The arabinofuranosyl analogues were prepared by the ...
Pentachlorophenol (PCP) is present in most environmental compartments, including those which result in direct human exposure. This paper assesses the contribution made by different exposure routes and illustrates that the average non-occupationally exposed UK individual absorbs 0.05, 0.32 and 4.16 μg PCP per day from air inhalation, water and diet ingestion, giving a total absorption of 4.53 μg (total intake being 5.7 μg). Using data from other sources it appears that most human PCP body burdens are in the region of 550 μg. Using the body burden and calculated daily intakes it is concluded that either the half-life of PCP in the human body has been underestimated or that the UK body burden is below that found in other countries.. ...
It is usually more convenient to base programs for nonlinear regression on matrix algebra. This is the approach taken in higher level mathematical programming software such as that provided by Matlab and Mathcad (sources for the Matlab and Mathcad software are listed at the end of this chapter). The principles are exactly the same as in the algebraic approach discussed above, but matrix methods facilitate organization and manipulation of the data.. In matrix notation, the straight-line model can be expressed as [3, 5]. where Y is a vector containing the n values of y; (meas), X is an n X 2 sample matrix, e is a vector containing the observed residuals, and b is the vector containing values of the slope and intercept. For an example with n = 3, eq. (2.17) can be represented as in Box 2.1.. ...
2,2,2-Trichloro-1-(1-methyl-1H-pyrrol-2-yl)-1-ethanone chemical properties, What are the chemical properties of 2,2,2-Trichloro-1-(1-methyl-1H-pyrrol-2-yl)-1-ethanone 21898-65-7, What are the physical properties of 2,2,2-Trichloro-1-(1-methyl-1H-pyrrol-2-yl)-1-ethanone ect.
Poster (2011, May). Myeloperoxidase (MPO) plays a key role in inflammatory response and constitutes a target for new drug development. The effects of some benzoic acid analogs were studied on the specific activity of human ... [more ▼]. Myeloperoxidase (MPO) plays a key role in inflammatory response and constitutes a target for new drug development. The effects of some benzoic acid analogs were studied on the specific activity of human MPO measured by SIEFED ("Specific Immunologic Extraction Followed by Enzymatic Detection"), an original method that consists of incubation of the compound with MPO, followed by capture of the enzyme by specific antibodies, washing (elimination of the compounds) and enzymatic detection of the immunocaptured enzyme. The compounds tested at 10-4, 10-5 and 10-6 M were studied in terms of structure activity relationship. Gallic acid (3,4,5-trihydroxybenzoic acid) with 3 hydroxyl groups had an important dose dependent inhibitory effect on MPO activity. Other molecules ...
NTP STATISTICAL ANALYSIS OF SURVIVAL DATA REPORT: PEIRPT11 LAB: Battelle Columbus DATE: 09/09/94 EXP: 05073 TECHNICAL GRADE PENTACHLOROPHENOL TIME: 05:37:17 TEST: 01 CAGES FROM 0000 TO LAST CAGE PAGE: 1 TEST TYPE: CHRONIC ROUTE: DOSED FEED NTP C#: 55378 CONT: N01-ES-38068 CAS: 87-86-5 PATHOLOGIST: R. PERSING S. EUSTIS -------------------------------------------------------------------------------- REASONS FOR REMOVAL: ALL REMOVAL DATE RANGE: ALL TREATMENT GROUPS: INCLUDE ALL NTP STATISTICAL ANALYSIS OF SURVIVAL DATA REPORT: PEIRPT11 LAB: Battelle Columbus DATE: 09/09/94 EXP: 05073 TECHNICAL GRADE PENTACHLOROPHENOL TIME: 05:37:17 TEST: 01 CAGES FROM 0000 TO LAST CAGE TEST TYPE: CHRONIC ROUTE: DOSED FEED NTP C#: 55378 CONT: N01-ES-38068 CAS: 87-86-5 PATHOLOGIST: R. PERSING S. EUSTIS TECHNICAL GRADE PENTACHLOROPHENOL STATISTICAL ANALYSIS OF SURVIVAL DATA MALE MICE FIRST TERMINAL SACRIFICE AT 729 DAYS INDIVIDUAL SURVIVAL TIMES (DAYS) ...
Often, nonparametric analysis only includes continuous regressors; however, our data also includes an unordered categorical variable, the type of specialty. Although it is possible to split the data into different categories, and estimate the functions for each specialty, the limited number of observations in the data would raise serious efficiency concerns. Instead, the analysis follows Racine and Li (2004), who propose a natural extension of Aitchison and Aitken (1976) to develop a discrete kernel.3 For continuous data, on the other hand, a number of different univariate kernels are available, such as the Gaussian and Epanechnikov kernels. In this analysis, the second-order Gaussian kernel is applied; other kernels were also considered, but did not influence the reported results. The discrete and continuous kernels are combined into a product kernel, simply the multiple of each of the kernels.. Nonparametric estimation follows an approach that is similar to weighted least squares regression, ...
All experimentally characterized proteins in this family are 1,4-benzoquinone reductases. These are intracellular enzymes involved in the biodegradation of aromatic compounds and in the protection of fungal cells from reactive quinone compounds ...
Abstract. A highly sensitive, simple and accurate spectrophotometric method has been developed for quantitative determination of sulfamethoxazole(SMX) in both pure form and pharmaceutical preparations. In this method SMX is diazotized with equimolar of sodium nitrite(NaNO2) in acid medium of hydrochloric acid to form diazonium ion , which is reacted with 2,4,6-trihydroxybenzoic acid in alkaline medium of NaOH to form a yellow water soluble azo dye that has absorption maximum at 416 nm versus reagent blank. Beers law is obeyed over the concentration range 0.2-16 µg. ml-1 with an excellent determination coefficient (r2= 0.9996) and molar absorptivity 1.84×104 l.mol-1.cm-1. The recoveries are obtained in the range of 97.8 - 99.8% and the relative standard deviation is better than ±0.23% . The stoichiometry of the resulting azo dye has been also worked out and it is found to be 1:1 SMX: 2,4,6-trihydroxybenzoic acid. This method has been applied successfully for the determination of SMX in ...
The invention relates to benzoquinone ansamycin analogs useful for the treatment of cancer and other diseases or conditions characterized by undesired cellular proliferation or hyperproliferation. Therapies involving the administration of such benzoquinone ansamycin analogs, optionally in combination with an inhibitor of an HSP90 client protein, are useful to treat cancer and non-cancerous disease conditions.
Mono- and Stereopictres of 5.0 Angstrom coordination sphere of Bromine atom in PDB 1o2y: Elaborate Manifold Of Short Hydrogen Bond Arrays Mediating Binding of Active Site-Directed Serine Protease Inhibitors
Mono- and Stereopictres of 5.0 Angstrom coordination sphere of Bromine atom in PDB 1o2w: Elaborate Manifold Of Short Hydrogen Bond Arrays Mediating Binding of Active Site-Directed Serine Protease Inhibitors
The invention relates to a new type of highly polar, at least double-negatively charged redox-active benzoquinones, notably derived from Coenzyme Q0, Q1 and dimethoxy benzoquinones, its production and use. The production of these benzoquinones comprises the reaction of dimethoxy benzoquinones with highly alkaline aqueous solutions. The benzoquinones of the invention have various potential applications in pharmaceutical and cosmetic industry (namely as antioxidants, anti-ageing agents and the like), in organic synthesis, metal complexations, metal separations, potentiometric titrations, interfacial catalysis, and ion-transfer reactions across biological membranes.. ...
1-fluoro-4-(2,3,3-trichloro-1-cyclopropen-1-yl)benzene - chemical structural formula, chemical names, chemical properties, synthesis references
Simple and Rapid Spectrophotometric Determination of Titanium on Etched Aluminum Foils. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
If the variance-covariance matrix is singular, the corresponding distribution has no density. An example of this case is the distribution of the vector of residual-errors in the ordinary least squares regression. Note also that the Xi are in general not independent; they can be seen as the result of applying the matrix A to a collection of independent Gaussian variables Z. ...
AFMAN 24-204(I)/TM 38-250/NAVSUP PUB 505/MCO P4030.19H/ DLAI 4145.3 189 11 DECEMBER 2001 Reportable Reportable Hazardous Substance Quantity (RQ) Hazardous Substance Quantity (RQ) Pounds Pounds (Kilograms) (Kilograms) Osmium tetroxide 1000 (454) Phenol, 2,4-dinitro- 10 (4.54) 7-Oxabicyclo[2.2.1]heptane-2,3- dicarboxylic acid 1000 (454) Phenol, methyl- 100 (45.4) 1,2-Oxathiolane, 2,2-dioxide 10 (4.54) Phenol, 2-methyl-4,6-dinitro- 10 (4.54) 2H-1,3,2-Oxazaphosphorin-2-amine, N,N-bis(2-chloroethyl) tetrahydro-2- oxide 10 (4.54) Phenol, 2,2 -methylenebis [3,4,6-trichloro- 100 (45.4) Oxirane 10 (4.54) Phenol, 2-(1-methylpropyl)-4,6- dinitro 1000 (454) Oxiranecarboxyaldehyde 10 (4.54) Phenol, 4-nitro- 100 (45.4) Oxirane, (chloromethyl)- 100 (45.4) Phenol, pentachloro- 10 (4.54) Paraformaldehyde 1000 (454) Phenol, 2,3,4,6-tetrachloro- 10 (4.54) Paraldehyde 1000 (454) Phenol, 2,4,5-trichloro- 10 (4.54) Parathion 10 (4.54) Phenol, 2,4,6-trichloro- 10 (4.54) Pentachlorobenzene 10 (4.54) Phenol, ...
Article Transcriptional profiling of the soil invertebrate (Folsomia candida) in pentachlorophenol contaminated soil. Pentachlorophenol (PCP) as a widely used pesticide is also considered to be an endocrine disruptor. Molecular effects of chemicals w...
Studies with four benzoquinones, viz. juglone, embelin, maesaquinone and maesanin, on rat liver mitochondria oxidative phosphorylation have been carried out. Three of the benzoquinones are uncouplers in the order juglone , maesoquinone , embelin, while maesanin is an inhibitor of electron transport and oxidative phosphorylation ...
J. O. Midiwo, A. Yenesew, B. F. Juma, S. Dereses, J. A. Ayoo, A. Aluoch and S. Guchu There are several described medicinal plants in Kenya from a flora of approximately 10,000 members. Strong cross-medical information from the 42 ethnic groups points to the high potential of some of these species. The Myrsinaceae are well established ethno-anthelmintics and anti-bacterials. They are harbingers of long alkyl side chain benzoquinones which clearly have a protective function from their histochemical disposition. The main benzoquinone in the sub-family Myrsinodae is embelin while for the Maesodae it is maesaquinone together with its 5-acetyl derivative; the distribution of these benzoquinones by their alkyl side chain length or the presence/absence of a 6-methyl group is in accord with morphological sub-family de-limitation. The benzoquinones showed anti-feedant, anti-microbial, phytotoxic, acaricidal, insecticidal and nematicidal activity. Many other benzoquinones of medium and minor concentration ...
Current models of evaluation and accountability utilize varying unadjusted measures of student achievement to reward or sanction schools. These unadjusted accountability indicators do not account for differences in student or school characteristics that contribute to variations in assessment results. Since the Coleman Report (1966), a guiding principle in accountability design has been that educational outcomes data should be used only after the effects of institutional characteristics have been statistically removed. Such indices are called adjusted indicators, where an adjustment is either statistical or through aggregation. ❧ The purpose of this study is to analyze the reliability (internal consistency and test-retest) and validity (discriminant, convergent, and concurrent) of six available accountability indicator systems: (a) API improvement scores, (b) APISED scores (SED = socioeconomically disadvantaged), (c) similar schools scores, (d) LA Times value-added scores, (e) academic growth ...
Acetic acid, trichloro-, pentafluorophenyl ester | C8Cl3F5O2 | CID 71389174 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more.
1,2,3-trichloro-5-nitrobenzene 20098-48-0 NMR spectrum, 1,2,3-trichloro-5-nitrobenzene H-NMR spectral analysis, 1,2,3-trichloro-5-nitrobenzene C-NMR spectral analysis ect.
In this reaction, the hydrogen atom that belongs to cellulose hydroxyl is replaced by an acetic group from acetic anhydride, yielding a carboxylic acid and an ester group in the wood, which is less polar to strong hydroxyl. This strategy renders wood more compatible with apolar polymers such as polyolefins.. Hence, the objectives of this study were to verify the effects of the proportion of acetic acid/anhydride on the acetylation of wood flour at varying times and temperatures and to examine hydroxyl and carbonyl groups by FTIR. The influence of these parameters was verified by experiments with a factorial design and partial least squares regression, both useful techniques for obtaining information concerning the effect of parameters in a given process.25-28 EXPERIMENTAL. Materials. Wood flour (100 mesh) from Pinus sp. trees, with a density of 0.25 g/cm³, was supplied by Pinhopó Ltda. Acetic acid and acetic anhydride (both from Biotec) were used in different ratios in the acetylation ...
Oxidation of quercetin by air oxygen takes place in water and aqueous ethanol solutions under mild conditions, namely in moderately-basic media (pH ∼ 8-10) at ambient temperature and in the absence of any radical initiators, without enzymatic catalysis or irradiation of the reaction media by light. The principal reaction products are typical of other oxidative degradation processes of quercetin, namely 3,4-dihydroxy-benzoic (proto-catechuic) and 2,4,6-trihydroxybenzoic (phloroglucinic) acids, as well as the decarboxylation product of the latter - 1,3,5-trihydroxybenzene (phloroglucinol). In accordance with the literature data, this process involves the cleavage of the γ-pyrone fragment (ring C) of the quercetin molecule by oxygen, with primary formation of 4,6-dihydroxy-2-(3,4-dihydroxybenzoyloxy)benzoic acid (depside). However under such mild conditions the accepted mechanism of this reaction (oxidative decarbonylation with formation of carbon monoxide, CO) should be reconsidered as preferably an
Methods for the determination of pentachlorophenol (PCP) in water and aquifer sediments are presented. Reverse-phase high-performance liquid chromotography employing ion suppression and gradient elution is used. PCP can be determined directly in water at a lower limit of detection Of 0.2 micrograms per liter. For extracts of sediment, PCP can be determined to a lower limit of 1.0 micrograms per kilogram....
Currently, many studies have focused on the magnitude of coherence with less emphasis on the time delay, or have mostly used only one method to establish the temporal relationship between the sensorimotor cortex and the peripheral muscles. Here, the time delays using inverse Fast Fourier transformation (IFFT), least squares regression analysis (LSR), weighted least squares regression analysis (WLSR), maximum coherence (MAX-COH) and mean of significant coherences (MEAN-COH) methods in the same subjects are compared to clarify the best method(s) for electroencephalography (EEG)- electromyography (EMG) temporal analysis. EEG activity and surface EMG activity from the first dorsal interosseous (FDI) muscle of the right hand were recorded in eight normal subjects during a weak contraction task. The current source density (CSD) reference method was estimated and used in the phase and temporal analysis. For the EEG and EMG time delay in the same subjects, MAX-COH, MEAN-COH and LSR methods are found to ...
Four naturally occurring dimeric phenylethyl benzoquinones, parvistemins A-D, were isolated from the aerial parts of Stemona parviflora Wright. Their constitutions were established by spectroscopic methods. Due to restricted rotation about the central biaryl axis, the compounds are chiral, although racemic. Their two respective atropo-enantiomers were resolved by HPLC on a chiral phase and were stereochemically characterized online, in hyphenation with circular dichroism (CD) spectroscopy (LC-CD coupling), combined with quantum chemical CD calculations ...
Phenol, 2,3,4-trichloro-, acetate | C8H5Cl3O2 | CID 522000 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more.
The main objective of this paper is to apply genetic programming (GP) with an orthogonal least squares (OLS) algorithm to derive a predictive model for the compressive strength of carbon fiber-reinforced plastic (CFRP) confined concrete cylinders. The GP/OLS model was developed based on experimental results obtained from the literature. Traditional GP-based and least squares regression analyses were performed using the same variables and data sets to benchmark the GP/OLS model. A subsequent parametric analysis was carried out and the trends of the results were confirmed via previous laboratory studies. The results indicate that the proposed formula can predict the ultimate compressive strength of concrete cylinders with an acceptable level of accuracy. The GP/OLS results are more accurate than those obtained using GP, regression, or several CFRP confinement models found in the literature. The GP/OLS-based formula is simple and straightforward, and provides a valuable tool for analysis. ...
The fragile gene, encompassing the chromosomal fragile site FRA3B, can be an early target of DNA damage in precancerous cells. can occur in regular lead and cells to regions of metaplasia with minimal FHIT expression. Loss of the next allele can result in complete lack of FHIT manifestation, which can be seen in many dysplastic Read More. ...
Cold-soak wood preservation by Ernest Wohletz; 3 editions; First published in 1848; Subjects: Pentachlorophenol, Preservation, Wood
April 2017: Congratulations to Rakesh and Samya on their publication in ACS Chem. Biol. concerning irreversible inhibition of DNA polymerase beta and synergistic effects in HeLa cells ...
Bergenin alias Cuscutin is trihydroxybenzoic acid glycoside. It is the C-glycoside of 4-O-methyl gallic acid. It possesses an O-demethylated derivative called norbergenin. These are chemical compounds and drugs of Ayurveda, commonly known as Paashaanbhed. It shows a potent immunomodulatory effect. Bergenin can be isolated from Bergenia species like Bergenia ciliata and Bergenia ligulata, from rhizomes of Bergenia stracheyi. It is also found in the stem bark of Dryobalanops aromatica, in Ardisia elliptica and in Mallotus japonicus.
Phytoconstituents like many polyphenols are poorly absorbed either due to their multiple-ring large size molecules which cannot be absorbed by simple diffusion, or due to their poor miscibility with oils and other lipids, severely limiting their ability to pass across the lipid-rich outer membranes of the enterocytes of the small intestine. Water-soluble phytoconstituent molecules (mainly polyphenols) can be converted into lipid-compatible molecular complexes, which are called Phytosomes. Gallic acid (GA, 3,4,5-trihydroxybenzoic acid), a naturally occurring plant phenol. So the following study was undertaken to evaluate the protective effects of gallic acid and gallic acid Phytosomes (GAP) at different doses against CCl4 induced hepatic and renal damage in albino rats. Liver damage was induced in Wister albino rats by administering CCl4 (1.5 ml/kg, i.p) once only. Simultaneously, GAP (40, 60 mg/kg, p.o.), GA (100 and 200 mg/kg, p.o.), and the reference drug silymarin (50 mg/kg b.w.).were administered
Angewandte Chemie Bioorganic Chemistry Irreversible Inhibition of Metallo-b-lactamase (IMP-1) by 3-(3-Mercaptopropionylsulfanyl)propionic Acid Pentafluorophenyl Ester** Hiromasa Kurosaki,* Yoshihiro Yamaguchi, Toshihiro Higashi, Kimitaka Soga, Satoshi Matsueda, Haruka Yumoto, Shogo Misumi, Yuriko Yamagata, Yoshichika Arakawa, and Masafumi Goto Pathogenic bacteria that produce metallo-b-lactamases (MBLs) are emerging as a new challenge to the medical community. These enzymes catalyze the hydrolysis of a wide spectrum of b-lactams, including carbapenems such as imipenem, some of which are coded in transferable plasmids.[1, 2] Among the currently known MBLs, IMP-1, a member of subclass B1, which is encoded by the blaIMP gene included in the integron structure,[2, 3] rapidly spreads by facile horizontal gene transfer to other bacteria.[4] Moreover, many of the currently used serine b-lactamase inhibitors such as clavulanic acid, sulbactam, and tazobactam are ineffective against MBLs. Thus, the ...
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Sigma-Aldrich offers a diverse array of hard and soft Lewis acids from the traditional titanium tetrachloride and boron trifluoride to Montmorillonite powders.
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Chloranil "Chloranilic acid". Sigma-Aldrich. Mostafa, S. I. (1999). "Complexes of 2,5-Dihydroxy-1,4-Benzoquinone and ...
The hydrolysis of HCP gives chloranil. S. Gali, C. Miravitlles and M. Font-Altaba "Hexachlorocyclohexa-2,5-dienone" Acta ...
Synthesis of DDQ involves cyanation of chloranil. Thiele and Günther first reported a 6-step preparation in 1906. The substance ...
Hydrochloric acid and potassium chlorate give chloranil. Potassium permanganate in neutral solution oxidizes it to nitrobenzene ...
The Molybdenum complex is activated with an oxidant such as chloranil. The result of the charge transfer facilitates ring ...
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 amino with chloranil. Chamberlain, Terence "Dioxazine violet pigments" from ...
I. The Use of the Chloranil Electrode in Glacial Acetic Acid and the Strength of Certain Weak Bases". Journal of the American ...
Chloranil Lawsone alizarin DDQ A large scale industrial application of quinones is for the production of hydrogen peroxide. 2- ... Strongly oxidizing quinones include chloranil and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (also known as DDQ). 9,10- ...
In the case at hand, heating acetate (1) with chloranil gives the conjugated dieneone (2), and reaction of that compound with ... Chloranil (tetrachloroquinone) is the forerunner of dichlorodicyanoquinone (DDQ), a reagent used extensively for introducing ...
695-99-8]) Chloranil, 1,4-C6Cl4O2, a stronger oxidant and dehydrogenation agent than 1,4-benzoquinone. Ambazone can be obtained ...
6-diene with chloranil (11). Acetylation under forcing conditions completes the synthesis of melengesterol acetate. ...
... as well as chloranil in a single reaction; the 4,6-diene, (medrogesterone), is obtained directly from this step. Medrogestone ...
... organic oxidation with P-chloranil in toluene 2 hours reflux and 81% yield c] Bishydroxylation with N-Methylmorpholine N-oxide ...
... followed by oxidation and ring closure with p-chloranil: Corrole has several important differences from porphyrin. The first is ...
... chloranil MeSH D02.806.250.280 --- dibromothymoquinone MeSH D02.806.250.700 --- plastoquinone MeSH D02.806.250.900 --- ...
... which is oxidized to dipyrromethene using a quinone oxidant such as DDQ or p-chloranil. Alternatively, dipyrromethenes are ...
... chloranil → VO(mes)3 VOCl3 + ZnPh2 → VOPhCl2 Vanadium compounds appear as catalysts and reagents in several specific reactions ...
... charge-transfer complexes of Ponceau S with p-chloranil, chloranilic and picric acids". Research on Chemical Intermediates. doi ...
... fungicides carbendazim carboxin carpropamid carvone Cheshunt mixture chinomethionat chlobenthiazone chloraniformethan 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. ...
Find out information about chloranil. C6Cl4O2 Yellow leaflets melting at 290°C; soluble in organic solvents; made from phenol ... by treatment with potassium chloride and hydrochloric acid; used as... Explanation of chloranil ... chloranil. Also found in: Dictionary, Wikipedia.. Related to chloranil: chloranilic acid, DDQ chloranil. [klȯr′an·əl] (organic ... Chloranil , Article about chloranil by The Free Dictionary https://encyclopedia2.thefreedictionary.com/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. ...
Chloranil. Dont know what are you goung to use it for, but DDQ is a substitute in many processes. ... What exactl is ortho-chloranil?. I can already see the posts instructing me to google it so dont bother, I already have, and ... What Im hoping for here is a general discription of ortho-chloranil, and if possible, any information relating to its purchase ... This patent gives a continuous lab-scale process for making o-chloranil from tetrachlorocatechol via chlorination of catechol ...
The ground state geometries of electron donor-acceptor (EDA) complexes between o-chloranil and a series of phenols have been ... Charge-transfer transition energies of EDA complexes between o-chloranil and a series of phenols: A correction with AMI results ... chloranil from the phenol moiety; the theoretical transition energies, after correction for salvation, have been found to agree ...
We are Professional Manufacturer of Chloranil Application company, Factory & Exporters specialize in Chloranil Application wiht ... Chloranil Application - manufacturer, factory, supplier from China. (Total 1 Products for Chloranil Application) ... This Chloranil Application is incredible. And I really appreciated the fast response of the service. ... I really like the Chloranil Application . When I received this product, it was completely packaged and included with detailed ...
Chloranil suppliers, Chloranil exporters, Chloranil importers. Get contact address of Chloranil manufacturing and supplying ... Manufacturer of Chloranil (2,3,5,6-Tetra Chloro-1,4-Benzo Quinone) (99%), BDSA (4,4-Diamino Diphenyl-2,2-Disulphonic Acid ... Exporter of Dyes Intermediates : Alpha Naphthol, Anthranilic Acid, Beta Naphthol Intermediates, Benzyl Chloride, Chloranil, H ... Dealing in Acrylamide, Aniline Oil, Carbazole, Chloranil, Diethyl Malonate. Epichlorohydrin, Ethyl Cyano Acetate, Ethyl 2- ...
toxic effects; Germany; chloranil; carbon disulfide; ecotoxicology; o-chloronitrobenzene; p-chloronitrobenzene; nonylphenol; m- ... carbon disulfide and chloranil) evaluated in earlier BUA reports. The new data relate mainly to ecotoxicological aspects and ...
Poly(epoxy-polyisocyanate) silicate foamed products are produced by mixing and reactng an epoxide compound, an oxidated silicon compound and a polyisocyanate in the presence of a Lewis acid. The foam produced by this process may be utilized for thermal and sound insulation.
The crystal structure of the chloranil-hexa-methylbenzene complex. T. T. Harding and S. C. Wallwork ...
4-Chloranil. 250 mg. DRE-C11130000. Add to basket 4-Chloro-2-methylaniline. 250 mg. DRE-C11430000. Add to basket ...
4-Chloranil. 250 mg. DRE-C11130000. Add to basket 4-Chloro-2-methylaniline. 250 mg. DRE-C11430000. Add to basket ...
Chloranil - Similar structures search, synonyms, formulas, resource links, and other chemical information. ... Substance Name: Chloranil. RN: 118-75-2. UNII: 01W5X7N5XV. InChIKey: UGNWTBMOAKPKBL-UHFFFAOYSA-N. Note. *. A quinone fungicide ...
with p-chloranil to Engl., 33:12, 1246- give a benzene- 47 at 1246. containing macrocycle called "benziporphin."1994 Performed ... Following this, 100 mg of p-chloranil (4.0 10-4) was added, and the reaction mixture was refluxed for 20 minutes. The solution ... Examples of such useful oxidizing agents include dichloro-dicyanobenzoquinone ("DDQ"), o- and p-chloranil, O2 gas, iodine (I2) ... are selected from the group consisting of DDQ or p-chloranil in dichloromethane or toluene, or O2 gas bubbled through an ...
Chloranil * p-chloroanile * Tetrachlor-p-benzochinon * Tetrachloro-1,4-benzoquinone * Tetrachloro-p-benzoquinone ...
Health and environmental effects profile for chloranil.. CORP Author. Environmental Protection Agency, Cincinnati, OH. ... Chloranil ; Toxic substances ; Biological accumulation ; CAS 118-75-2 ; Pharmacokinetics ; Environmental fate ; Environmental ...
p-Chloranil, 97%. * A15297. 3-Pentanone, 99%. * A15656. Sodium pentacyanonitrosylferrate(III) dihydrate, 98+% ...
p-Chloranil, 97%. * A14716. 4-Benzyloxy-3-methoxybenzaldehyde, 98%. * A15555. Methyl cyanoacetate, 99% ...
Chloranil "Chloranilic acid". Sigma-Aldrich. Mostafa, S. I. (1999). "Complexes of 2,5-Dihydroxy-1,4-Benzoquinone and ...
Recently chloranil was employed as cyclising agent for the synthesis of dissymmetric TPDOs, however, the product was obtained ... An Efficient Microwave Assisted Synthesis of Triphenodioxazines Using Chloranil as Oxidizing Agent ...
Conditions: (i) BF3·OEt2, chloranil, Δ. See Ref. [41] for details. ...
2g of chloranil was stirred into a solution of 5g of sodium nitrite in 200ml of water. Gradually all the chloranil went into ... Chloranil can also be used to prepare nitranilic acid.. Chloranil according to ber, 20, 2027-2031 (1887) when treated with an ... chloranil is very frequently formed ; and as chloranil itself breaks up into chloropicrin by the action of aqua regia, this is ... Chloranil : A slurry of 5.0 grams of salicylic acid and 100 ml of concentrated hydrochloric acid was heated to 80ºC and 5.0 ...
A solution obtained by dissolving 5 g of p-chloranil in 100 mL of tetrahydrofuran was added, and the reaction solution was ... The solution was concentrated, and the p-chloranil was filtered out. Dichloromethane/hexane=1:1 was used as the eluant, the ...
Nutrition · GSTCBQ target residues · Mapping site-specific mutagenesis · Binding Sites · Chloranil · Enzyme Inhibitors · ... Chemicals/CAS: 2-gluthionyl-3,5,6-trichloro-1,4-benzoquinone, 117383-28-5; Chloranil, 118-75-2; Enzyme Inhibitors; Glutathione ...
Hydrochloric acid and potassium chlorate give chloranil. Potassium permanganate in neutral solution oxidizes it to nitrobenzene ...
A chloranil color test for monitoring coupling completeness in solid phase peptide synthesis. E. Gross, and J. Meierhofer, eds ... The occurrence of coupling was confirmed by the Chloranil test (19). Modified agarose was then dissolved in 50 ml of DMSO again ...
  • Because of its great resistance to further oxidation, chloranil is formed as the final product of the chlorate-HCl oxidation of many aromatic compds. (sciencemadness.org)
  • In December 1974, I was called by the plant supervisor to come out to where the day shift was running another 2000-gal oxidation of tetrachlorocatechol using a process I'd developed for the production of high-purity o-chloranil. (blogspot.com)
  • When the oxidation was complete, we centrifuged pure o-chloranil and washed the cakes with hexane. (blogspot.com)
  • Chloranil is a quinone with the molecular formula C6Cl4O2. (wikipedia.org)
  • Al-Hamidi, A. A. A., Shehu, R. A. and Duhaiman, A. S. Inhibition of camel lens z -crystallin/NADPH: quinone oxidoreductase activity by chloranil. (edu.sa)
  • Chloranilic acid 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) Chloranil at Sigma-Aldrich J.-M. Lü, S. V. Rosokha, I. S. Neretin and J. K. Kochi, "Quinones as Electron Acceptors. (wikipedia.org)
  • When reacted with chlorine, aqua regia or potassium chlorate in the presence of hydrochloric acid, picric acid yields chloranil along with chloropicrin. (sciencemadness.org)
  • If not p-DCB then nitration to activate one of the chlorines then remove with NaOH giving mainly 4-chloro-2,6-dinitrophenol, its known that picric acid and p-chlorophenol can be oxidised/chlorinated to chloranil so that probably has merit if p-DCB itself is unreactive. (sciencemadness.org)
  • The ground state geometries of electron donor-acceptor (EDA) complexes between o -chloranil and a series of phenols have been optimised by AMI method, adopting a 'super molecule' model for each DA adduct. (niscair.res.in)
  • Infrared spectra of acridine orange and its charge transfer complexes with acceptors such as chloranil, 2,3-dichloro-5,6-dicyano- p -benzoquinone, 7,7,8,8-tetracyano- p -quinodimethane and tetracyano- p -ethylene are reported. (niscair.res.in)
  • The method is based on the reaction, on the filter paper surface, between the drug and p-chloranil producing a colored compound. (unesp.br)
  • The best reaction conditions were obtained with 20 μL of atenolol solution and 20 μL of p-chloranil. (unesp.br)
  • T. Christensen, "Qualitative test for monitoring coupling completeness in solid phase peptide synthesis using chloranil," Acta Chemica Scandinavica , vol. 33, pp. 763-776, 1979. (hindawi.com)
  • we have Chloranil tech grade and pharma grade CAS No 118-75-2 Molecular Formula C6Cl4O2 Molecular Weight 245.88 Appearance Yellow powder or cr. (kitairu.net)
  • Five source profiles were extracted from the PMF model applied to the sediment samples including chloranil, combustion, polychlorinated biphenyl impurities, mixed urban sources and. (environmental-expert.com)
  • Recently chloranil was employed as cyclising agent for the synthesis of dissymmetric TPDOs, however, the product was obtained indirectly through bisphenoxy or phenoxazine tricyclic intermediate [14, instead of dianilide intermediate. (thefreedictionary.com)