- Synthesis of ethylene bis [(2-hydroxy-5,1,3-phenylene) bis methylene] tetraphosphonic acid and their anticorrosive effect on carbon steel in 3%NaCl solution
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The inhibition performance of the newly synthesized Ethylene bis [(2-hydroxy-5,1,3-phenylene) bis methylene] tetraphosphonic acid (ETPA) toward carbon steel in 3% NaCl was investigated at different concentrations using potentiodynamic polarization (PDP) and impedance spectroscopy (EIS) methods. It was found that the inhibition capability was increased with increasing inhibitor dose and reach 92% at 10?3 mol/L. Also, Polarization curves showed that ETPA acts as a mixed type inhibitor with predominantly control of anodic reaction. The new inhibitor was investigated by different spectroscopic methods such as 1H, 13C and 31PNMR. The quantum parameters such as absolute electronegativity (χ), energy gap ΔE (EHOMO-ELUMO), global softness (σ), global hardness (η), electrophilicity index (ω) and the number of transfer electrons (ΔN) are calculated by density functional theory (DFT). The experimental also correlated with density functional theory results. The calculations show that ETPA has high density of negative charge located on the oxygen atoms of the phosphonate group facilitating the adsorption of ETPA on the surface of carbon steel. The inhibition efficiency of ETPA was discussed in terms of blocking of electrode surface by adsorption of ETPA molecules through active centers. The adsorption of ETPA on the surface of carbon steel obeyed the Langmuir isotherm paradigm.
- Sait,Aliouane,Toukal,Hammache,Al-Noaimi,Helesbeux,Duval
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- COMPOUNDS, COJUGATES AND COMPOSITIONS FOR USE IN THE METHODS FOR TRANS-MEMBRANE DELIVERY OF MOLECULES
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The invention provides a system for the delivery of dmgs across biological membranes, including conjugates thereof, processes for their preparation and methods for their use.
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Paragraph 00130
(2020/03/23)
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- Method for preparation of bibenzyl compounds by photocatalytic one-step process
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The invention relates to a brand new low-cost method for synthesis of bibenzyl compounds. The method adopts green and clean light energy as the reaction energy, and takes toluene or a toluene derivative as the raw material to prepare bibenzyl compounds under the catalysis of a solid photocatalyst. The method is carried out at room temperature, and can prepare bibenzyl compounds directly by illumination. The reaction process includes: mixing a toluene derivative, a catalyst and a solvent, then putting the mixture into a pressure-resistant quartz container (larger than 1MPa), and performing replacement with inert gas, conducting illumination stirring at room temperature, and carrying out reaction for 1 or more hour. At the end of the reaction, the catalyst can be easily separated from the reaction system and can be recycled repeatedly, the reaction product can be separated by crystallization, and the yield of bibenzyl compounds can reach 3.21g (g catalyst)h. The method can be used for direct preparation of 1, 2-diphenylethane and natural bibenzyl drugs.
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Paragraph 0051-0054
(2019/07/04)
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- Synthesis and fungicidal activity of bioactive 4,4′-bis[4″-(N-benzylidinylamine)-3″-mercapto-1″,2″,4″-triazole-5″-yl methoxy]dibenzyl
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The reaction of 4,4′-diamino dibenzyl (I) with sodium nitrite and HCl at 0-5°C followed by hydrolysis gave 4,4′-dihydroxy dibenzyl (II), which on reaction with chloroacetic acid in presence of sodium carbonate yielded 4,4′-ethylenebisphenoxyacetic acid (I
- Dwivedi, Smriti,Singh, Pravin K.
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- Synthesis and structure–activity relationships of 1-benzylindane derivatives as selective agonists for estrogen receptor beta
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The estrogen receptor beta (ERβ) selective agonist is considered a promising candidate for the treatment of estrogen deficiency symptoms in ERβ-expressing tissues, without the risk of breast cancer, and multiple classes of compounds have been reported as
- Yonekubo, Shigeru,Fushimi, Nobuhiko,Miyagi, Takashi,Nakanishi, Osamu,Katsuno, Kenji,Ozawa, Motoyasu,Handa, Chiaki,Furuya, Noritaka,Muranaka, Hideyuki
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supporting information
p. 5895 - 5910
(2016/10/30)
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- Synthesis of 4,4'-Bis (Pyrimidinedione Acetamidoxy) bibenzyls as antifungal agents
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4,4'-Diaminobibenzyl (I) with sodium nitrite and HCl at 0-5° followed by hydrolysis gave 4,4'-dihydroxybibenzyl (II), which on reaction with chloroacetic acid in presence of sodium carbonate yielded 4,4'-ethylenebisphenoxyacetic acid (III). Nucleophilic s
- Dwivedi, Smriti,Siddiqui
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p. 433 - 436
(2019/01/21)
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- Understanding the reactivity of enol ether radical cations: Investigation of anodic four-membered carbon ring formation
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The reactivity of enol ether radical cations was investigated in anodic four-membered carbon ring formations, advancing the mechanistic understanding of these reactions. The mono-ring-containing aromatic cations were reduced through inter- or intramolecular electron transfer to give mono- or bis-ring-containing compounds, respectively. Small structural changes in the hydrocarbon linkers tethering two aromatic rings exerted a powerful effect on the efficiency of such electron transfer events.
- Yamaguchi, Yusuke,Okada, Yohei,Chiba, Kazuhiro
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p. 2626 - 2638
(2013/04/23)
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- Bibenzyl- and stilbene-core compounds with non-polar linker atom substituents as selective ligands for estrogen receptor beta
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A series of structurally simple bibenzyl-diol and stilbene-diol core molecules, structural analogs of the well-known hexestrol and diethylstilbestrol non-steroidal estrogens, were prepared and evaluated as estrogen receptor (ER) subtype-selective ligands. Analysis of their ERα and ERβ binding showed that certain substitution patterns engendered binding affinities that were >100-fold selective for ERβ. When further investigated in cell-based gene transcription assays, some molecules showed similarly high relative transcriptional potency selectivity in favor of ERβ. Interestingly, the most ERβ-selective molecules were those bearing non-polar substituents on one of the internal carbon atoms. These compounds should be useful probes for determining the physiological roles of ERβ, and they might lead to the development of more selective and thus safer pharmaceuticals.
- Waibel, Michael,De Angelis, Meri,Stossi, Fabio,Kieser, Karen J.,Carlson, Kathryn E.,Katzenellenbogen, Benita S.,Katzenellenbogen, John A.
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experimental part
p. 3412 - 3424
(2009/10/23)
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- STILBENES AND CHALCONES FOR THE PREVENTION AND TREATMENT OF CARDIOVASCULAR DISEASES
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The present disclosure provides non-naturally occurring polyphenol compounds that upregulate the expression of Apolipoprotein A-I (ApoA-I). The disclosed compositions and methods can be used for treatment and prevention of cardiovascular disease and related disease states, including cholesterol or lipid related disorders, such as, e.g., atherosclerosis.
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Page/Page column 172
(2015/06/03)
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- Low-valent titanium mediated synthesis of hydroxystilbenoids: Some new observations
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A series of phenolic stilbenoids possessing different numbers and positions of hydroxylation, partial methoxyl substituents and nature of olefinic moieties has been synthesized by McMurry coupling. It is found that the McMurry coupling of the phenolic aldehydes furnishes the dihydrostilbenes via an in situ hydrogenation, while the phenolic ketones give the stilbenes. Interestingly, the study also reveals that the low-valent titanium reagent (TiCl 3-Zn-THF) could selectively depyranylate phenolic -OTHP function without affecting alcoholic -OTHP group.
- Shadakshari,Rele,Nayak,Chattopadhyay
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p. 1934 - 1938
(2007/10/03)
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- Exciton and charge-transfer interactions in nonconjugated merocyanine dye dimers: Novel solvatochromic behavior for tethered bichromophores and excimers
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A series of merocyanine dye dimers tethered at different sites with spacers ranging from 0 to 5 methylene groups and the corresponding monomer have been synthesized. The formation, structure, and excited-state properties of the consequent merocyanine dye "aggregates" in solutions and in rigid glass have been studied by UV/visible absorption spectra, steady-state fluorescence, and fluorescence lifetime measurements. The dimers with 0 and 1 methylene spacers must exist in more-or-less extended conformations; consequently, they show a very weak and distance-dependent "J"-type exciton coupling, evident in both absorption and fluorescence spectra. For the dimers with 2, 3, and 5 methylene spacers, absorption spectra in nonpolar solvents are consistent with a largely extended configuration and little or no evident exciton coupling. However, for more polar solvents, a blue-shifted absorption spectrum is observed, suggesting a folded configuration resulting in an "H" dimer. For the latter dimers, fluorescence spectra in a variety of solvents show a pronounced red-shift, which is attributed to a folded "excimer". As anticipated from its structure, the merocyanine monomer shows a weak positive solvatochromic effect that may be correlated using the Taft-Kamlet π* parameter. Remarkably, both the "J" coupled dimer (n = 0) and the dimers having 2-5 methylene groups show a much stronger solvatochromic behavior than the monomer. The strong solvatochromic effects in these tethered dimers may be attributed to interchromophoric charge-transfer interactions in both ground and excited states.
- Lu, Liangde,Lachicotte, Rene J.,Penner, Thomas L.,Perlstein, Jerry,Whitten, David G.
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p. 8146 - 8156
(2007/10/03)
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- Processes for producing aromatic polycarbonate oligomer and aromatic polycarbonate
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A process for producing continuously an aromatic polycarbonate oligomer by reacting an aromatic dihydroxy compound and an alkali metal base or an alkaline earth metal base with a carbonyl halide compound comprises: (1) feeding continuously to a tank reactor an aromatic dihydroxy compound, water, a molecular weight controlling agent, a polymerization catalyst, a carbonyl halide compound, and an organic solvent, and an alkali metal base or an alkaline earth metal base in an amount of 1.15-1.6 equivalents based on the aromatic dihydroxy compound, (2) carrying out the reaction with a residence time as defined by the following formula, where X is an amount of the polymerization catalyst in terms of mole % based on the amount of mole of the aromatic dihydroxy compound fed per unit time, and Y is a residence time (min.), and (3) continuously withdrawing the reaction mixture from the tank reactor to obtain an aromatic polycarbonate oligomer having a number average molecular weight of 1,000-10,000. An aromatic polycarbonate is produced by polycondensation of the aromatic polycarbonate oligomer.
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- Method for preparing aromatic bischloroformate compositions
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Bischloroformate oligomer compositions are prepared by passing phosgene into a heterogeneous aqueous-organic mixture containing at least one dihydroxyaromatic compound, with simultaneous introduction of a base at a rate to maintain a specific pH range and to produce a specific volume ratio of aqueous to organic phase. By this method, it is possible to employ a minimum amount of phosgene. The reaction may be conducted batchwise or continuously. The bischloroformate composition may be employed for the preparation of cyclic polycarbonate oligomers or linear polycarbonate, and linear polycarbonate formation may be integrated with bischloroformate composition formation in a batch or continuous process.
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- Bischoloroformate preparation method with phosgene removal and monochloroformate conversion
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Aqueous bischloroformates are prepared by the reaction of a dihydroxyaromatic compound (e.g., bisphenol A) with phosgene in a substantially inert organic liquid (e.g., methylene chloride) and in the presence of an aqueous alkali metal or alkaline earth metal base, at a pH below about 8. After all solid dihydroxyaromatic compound has been consumed, the pH is raised to a higher value in the range of about 7-12, preferably 9-11, and maintained in said range until a major proportion of the unreacted phosgene has been hydrolyzed. At the same time, any monochloroformate in the product may be converted to bischloroformate.
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- Cyclic monocarbonate bishaloformates
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Cyclic monocarbonate bischloroformates are prepared by the reaction of a carbonyl halide such as phosgene with a bridged substituted resorcinol or hydroquinone such as bis(2,4-dihydroxy-3-methylphenyl)methane or bis(2,5-dihydroxy-3,4,6-trimethylphenyl)methane in the presence of aqueous alkali metal hydroxide. The cyclic monocarbonate bischloroformates may be used for the preparation of linear or cyclic polycarbonates containing cyclic carbonate structural units, which may in turn be converted to crosslinked polycarbonates.
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- Catalyst composition and method for selective dehydrogenation
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A method for selective dehydrogenation of a compound, comprising contacting a compound of the formula STR1 wherein each R1, R2, R3 and R4 is independently selected from the group consisting of H, (C1 -C20) alkyl, (C3 -C20) cycloalkyl, (C6 -C20) aryl, (C7 -C20) alkylaryl, (C7 -C20) aralkyl groups, as well as substituted (C1 -C20) alkyl, (C3 -C20) cycloalkyl, (C6 -C20) aryl, (C7 -C20) aralkyl and (C7 -C20) arylalkyl moieties, optionally further substituted with --OR, wherein R is R1, R2, R3 or R4 ; and wherein R1 and R2 or R3 and R4 may be joined as part of a ring structure, at a dehydrogenation temperature in the presence of a catalyst comprising about 0.01 wt %-19.9 wt % Pd and about 0.01 wt %-19.9 wt % Cu on a carbon support, wherein the total amount of (Pd+Cu) on the support is about 0.02 wt % to 20 wt %, the weight ratio of Pd:Cu is about 1:1 to 10:1, and the carbon support has a surface area of at least about 100 m2 /g and is essentially free of reactive sulfur. A selective dehydrogenation catalyst having the composition described supra is disclosed as is a method of preparing the same. This catalyst is highly selective for dehydrogenating a variety of substrates while minimizing the formation of unwanted hydrogenolysis by-products.
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- Polyetherimide bisphenol compositions
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Polyetherimide bisphenols and bischloroformates are prepared by the reaction of dianhydrides or certain bisimides with aminophenols or mixtures thereof with diamines. They are useful as intermediates for the preparation of cyclic heterocarbonates, which may in turn be converted to linear copolycarbonates. The bisphenols can also be converted to salts which react with cyclic polycarbonate oligomers to form block copolyetherimidecarbonates.
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- Preparation and Reactions of Dianions from the Cresols
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With n-BuLi/KO-t-Bu, protons are removed from the hydroxyl and methyl groups of cresols 5 to give dianions 6 in yields of 85percent (ortho), 95percent (meta), and 42percent (para).These dianions react with alkyl halides, Me3SiCl, Bu3SnCl, CO2, and oxidizing agents at carbon only and with dialkyl sulfates at both carbon and oxygen.Thus phenol derivatives bearing primary alkyl groups can be prepared from the corresponding methylphenols via dianions 6.
- Bates, Robert B.,Siahaan, Teruna J.
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p. 1432 - 1434
(2007/10/02)
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- Bisbenzoxazines and pharmaceutical use
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Compounds of the formula: STR1 wherein, R is H, alkyl, cycloalkyl, aryl, or heteroaryl; R1 is H, alkyl, cycloalkyl, aryl, heteroaryl, substituted heteroaryl, aralkyl, substituted aryl, halo, OR2, SR2, NR2, CF3, NO2, CN, COOR2, CHO, SO3 H or SO2 NH2, wherein R2 is H, methyl, ethyl or propyl; Y is STR2 Z is O, S, NH or CH2 ; X is --CH2 --, STR3 or --(CH2)n CHOH(CH2)n --; wherein R2 is H, methyl, ethyl or propyl; n is 1-10, and pharmaceutically acceptable salts thereof have antiallergy and antiinflammatory activity.
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- Hydrogenolysis of hydrobenzoins
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Hydrogenolysis of hydrobenzoins [1,2-bis(aryl)ethane-1,2-diols] in the presence of a catalyst comprising cobalt carbonyl yields 1,2-bis(aryl)ethanes. The process is particularly directed to the production of 1,2-bis(4-hydroxyphenyl)ethane from 4,4-dihydro
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- Electrolytic oxidative methyl-methyl coupling of cresol salts
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Electrolytic oxidation of cresol salts substituted with non-interfering, blocking substituents at least at the 2,4,6-positions relative to the phenolic oxyanion where at least one of the substituents is the cresolic methyl leads to methyl-methyl coupled dehydrodimeric cresols.
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