Search results for "Furan"
showing 10 items of 667 documents
Multivariate Correlation between Analytical Data for Various Organics Dissolved during Autohydrolysis of Silver Birch (Betula pendula) Chips and Trea…
2014
Autohydrolysis pre-treatments were performed for the production of hemicellulose-rich autohydrolysates from silver birch (Betula pendula) chips prior to chemical pulping. Pre-treatment conditions were varied with respect to time (from 30 to 120 min) and temperature (130 and 150 °C), covering a P-factor range from 10 to 238. Hydrolysates were analyzed in terms of carbohydrates, lignin, volatile organic acids, and furanoic compounds. The analytical data were subjected to various chemometric techniques to establish the relationships between dissolved organic components, hardwood and softwood used in the experiments, and applied pre-treatment conditions. Using this method, differences between t…
The M74 syndrome of baltic salmon (Salmo salar) and organochlorine concentrations in the muscle of female salmon
1997
Abstract Organochlorine concentrations in the muscle of female Baltic salmon (Salmo salar), ascending for spawning in the Simojoki River on the north-eastern coast of the Gulf of Bothnia from 1988 to 1992 are given in this paper in relation to reproduction success, monitored as viability of offspring. In spring 1992 and 1993 all the yolk-sac fry of 52 % and 75 % of the females, sampled in autumns 1991 and 1992 respectively, died due to the M74 syndrome, i.e., heavy mortality of yolk-sac fry (YSM). The TEOs of the most frequently detected polychlorinated dibenzofurans (PCDFs: 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF and 2,3,7,8-TeCDF) and those of coplanar PCBs (CB77, CB126 and CB169) were about twi…
Multivariate Correlation between Analysis Data on Dissolved Organic Material from Scots Pine (Pinus sylvestris) Chips and their Autohydrolysis Pre-Tr…
2013
Various chemometric techniques were used to establish the relationship between the autohydrolysis conditions prior to pulping and the chemical compositions of the soluble organic materials removed from Scots pine (Pinus sylvestris) wood chips. The aqueous chip pre-treatments (autohydrolysis) were administered at 130 °C and 150 °C for 30, 60, 90, and 120 min, and the hydrolysates obtained were characterized in terms of total carbohydrates (various mono-, oligo-, and polysaccharides together with uronic acid side groups), volatile acids (acetic and formic acids), lignin, and furans (furfural and 5-(hydroxymethyl)furfural). Based on the analytical data gathered, a relatively accurate model for…
A combined experimental and theoretical study of the thermal [3+2] cycloaddition of carbonyl ylides with activated alkenes
2018
International audience; 4-Benzoyl-3,5-diaryltetrahydrofuran-2,2-dicarbonitriles were first synthesized from 2,2-dicyano-3-aryloxiranes and chalcones at toluene reflux; the 4,5-cis products proved to be predominantly formed and were isolated. Whereas shortened reaction times were observed by using microwave irradiation or catalytic cuprous chloride, no significant stereoselectivity change was in general noticed. Reacting 2,2-dicyano-3-aryloxiranes with 2-cyclopentenone next afforded 3-aryl-4-oxohexahydro-1H-cyclopenta[c]furan-1,1-dicarbonitriles, and the endo stereoisomers were isolated. That no stereoselectivity change was noticed in the presence of cuprous chloride rather suggests an impac…
Physico-chemical stability of eribulin mesylate containing concentrate and ready-to-administer solutions.
2013
Objectives The aim of this study was to determine the stability of commercially available eribulin mesylate containing injection solution as well as diluted ready-to-administer solutions stored under refrigeration or at room temperature. Methods Stability was studied by a novel developed stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) assay with ultraviolet detection (detection wavelength 200 nm). Triplicate test solutions of eribulin mesylate containing injection concentrate (0.5 mg/mL) and with 0.9% sodium chloride solution diluted ready-to-administer preparations (0.205 mg/mL eribulin mesylate in polypropylene (PP) syringes, 0.020 mg/mL eribulin mesyl…
Eribulin Mesylate for the Treatment of Metastatic Hormone-refractory and Triple-negative Breast Cancer: A Multi-institutional Real-world Report on Ef…
2021
Objective Eribulin mesylate (EM) is a fully synthetic macrocyclic ketone analogue of the marine natural product halichondrin. EM has been reported to be active in metastatic breast cancer. In this paper, we report efficacy and safety of data of EM in a retrospective, real-world series of patients with poor prognosis, hormone-refractory, or triple-negative metastatic breast cancer. Materials and methods The analysis was carried out at 4 interrelated oncology centers. EM was delivered at the dose of 1.4 mg/m2 in 100 mL of normal saline over 2 to 5 minutes on days 1 and 8 every 21 days. EM was continued until disease progression or unacceptable toxicity. Side effects were reported every cycle …
Palladium on pumice: new catalysts for the stereoselective semihydrogenation of alkynes to (Z)-alkenes
2001
Abstract High selectivities (93–99%) and excellent stereoselectivities (>99%) in the semihydrogenation of CC triple bonds were achieved using palladium on pumice with a metal loading of 0.5, 1.5 or 3.0% wt as catalyst. The reactions were carried out in ethanol or tetrahydrofuran with only 2.5% of ethylenediamine allowing a self-terminating semihydrogenation independently on the CC triple bond.
ChemInform Abstract: Palladium on Pumice: New Catalysts for the Stereoselective Semihydrogenation of Alkynes to (Z)-Alkenes.
2010
Abstract High selectivities (93–99%) and excellent stereoselectivities (>99%) in the semihydrogenation of CC triple bonds were achieved using palladium on pumice with a metal loading of 0.5, 1.5 or 3.0% wt as catalyst. The reactions were carried out in ethanol or tetrahydrofuran with only 2.5% of ethylenediamine allowing a self-terminating semihydrogenation independently on the CC triple bond.
Synthesis and antibacterial activities of cadiolides A, B and C and analogues
2015
International audience; The one-pot multicomponent synthesis of natural butenolides named cadiolides A, B, C and analogues has been realized. The antibacterial structure activity relationship shows that the presence of phenolic hydroxyl groups and the number and position of bromine atoms on the different aromatic rings are important features for antibacterial activity, besides it was demonstrated the tolerance of both benzene and furan ring at position 3 of the butenolide nucleus. Furthermore, none of the most relevant antibacterial compounds showed any cytotoxicity in freshly isolated human neutrophils.
Urea as a PCDD/F inhibitor in municipal waste incineration.
2001
Emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from municipal waste incineration have been widely studied because of their extensive toxicity, and many efforts have been made to restrict their emissions. Although a number of chemical compounds have been shown in laboratory-scale tests to inhibit the formation of PCDD/Fs, few have been tested in pilot- or full-scale plants. This work evaluates the effect of urea as a PCDD/F inhibitor in a pilot-scale incinerator that uses refuse-derived fuel (RDF). The decomposition of urea under the test conditions was also studied using detailed kinetic modeling. An aqueous solution of urea was injected into the flue gas stream …