- Liquid-liquid equilibrium phase diagrams of polyethyleneglycol + sodium tartrate + water two-phase systems
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The phase diagrams of aqueous two-phase systems formed by water, sodium tartrate, and polyethyleneglycol of different molecular weights (600, 1000, 2000, 4000, 6000, and 8000) were determined at 298 K. The effect of NaCl on the liquid-liquid equilibrium was also analyzed. The binodal curves were satisfactorily described using a four-parameter sigmoidal equation. The tie lines were determined by combining a colorimetric method and density measurements. The reliability of the measured tie line compositions was ascertained by the Othmer-Tobias and Bancroft correlation equations.
- Malpiedi, Luciana Pellegrini,Fernandez, Cintia,Pico, Guillermo,Nerli, Bibiana
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- Collaborative effect of Mn-porphyrin and mesoporous SBA-15 in the enantioselective epoxidation of olefins with oxygen
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The rational design of heterogeneous, low cost transition metal complexes that can catalyze olefin with high enantioselectivity and activity has been a challenging goal for the synthetic chemist. In this study a chiral ion pair strategy was used for the synthesis of a biomimetic efficient manganese-tetrapyridylporphyrin (H2TPyP) catalyst for the asymmetric epoxidation of olefins with O2. Complex Mn-TPyP was covalently linked to mesoporous SBA-15 in heme-type environments and its counter ion was replaced by L-tartrate anion (SBA15-[Mn(TPyP)TA]). Chiral and achiral homogeneous analogous of Mn-TPyP were also prepared. The Mn-porphyrin confined in nanoreactors of SBA-15 exhibited enhanced activity (TOF = 652 h?1) and enantiomeric excess (ee 93%) compared with the value obtained when the same chiral catalyst functioned in homogeneous solution (TOF 97 h?1 and ee 83%) in the oxidation of 1-decene with O2/isobutyraldehyde. The high specific surface area, uniformly sized pore channels and site isolated active centers of the catalyst may contribute to the high activity and enantioselectivity. SBA15-[Mn(TPyP)TA] was structurally stable and could be recycled for repeated use. Total turnover number in the oxidation of styrene after five cycles was 47,400 with 86% epoxide selectivity and ee 86%.
- Berijani, Kayhaneh,Hosseini-Monfared, Hassan
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p. 113 - 120
(2017/11/10)
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- Non-caking salt composition, preparation process and use thereof
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The present invention relates to a sodium chloride composition comprising an iron complex of tartaric acid wherein between 55 and 90% by weight of the tartaric acid is meso-tartaric acid. The present invention furthermore relates to a process to prepare such a sodium chloride composition and to the use of such a sodium chloride composition.
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Page/Page column 11-12
(2015/01/06)
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- Production of tartrates by cyanide-mediated dimerization of glyoxylate: A potential abiotic pathway to the citric acid cycle
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An abiotic formation of meso- and dl-tartrates in 80% yield via the cyanide-catalyzed dimerization of glyoxylate under alkaline conditions is demonstrated. A detailed mechanism for this conversion is proposed, supported by NMR evidence and 13C-labeled reactions. Simple dehydration of tartrates to oxaloacetate and an ensuing decarboxylation to form pyruvate are known processes that provide a ready feedstock for entry into the citric acid cycle. While glyoxylate and high hydroxide concentration are atypical in the prebiotic literature, there is evidence for natural, abiotic availability of each. It is proposed that this availability, coupled with the remarkable efficiency of tartrate production from glyoxylate, merits consideration of an alternative prebiotic pathway for providing constituents of the citric acid cycle.
- Butch, Christopher,Cope, Elizabeth D.,Pollet, Pamela,Gelbaum, Leslie,Krishnamurthy, Ramanarayanan,Liotta, Charles L.
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supporting information
p. 13440 - 13445
(2013/09/24)
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- Platinum complexes containing chemically modified bile acids, having antitumor activity
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The present invention relates to platinum complexes containing bile acid derivatives having antitumor activity
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Page/Page column 2-3; 6
(2010/02/11)
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- Process for synthesis of D1 receptor antagonists
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In one embodiment, the present invention describes the synthesis of a compound of formula and intermediates therefor.
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Page/Page column 8
(2010/01/31)
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- Facile nitroxide-mediated oxidations of D-glucose to D-glucaric acid
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The oxidation of D-(+)-glucose to D-glucaric acid using the TEMPO-like nitroxide oxidation catalyst, 4-acetamido-2,2,6,6-tetramethyl-1-piperidinyloxy (4-acetamido-TEMPO) was carried out using several oxidizing agents and co-catalyst. The pH and temperature of the reactions were closely monitored to decrease degradations during the oxidation, and several isolation methods were explored.
- Merbouh, Nabyl,Francois Thaburet, Jean,Ibert, Mathias,Marsais, Francis,Bobbitt, James M
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- TEMPO-mediated oxidation of maltodextrins and D-glucose: Effect of pH on the selectivity and sequestering ability of the resulting polycarboxylates
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Maltodextrins were oxidized to polyglucuronic acids with the ternary oxidation system: NaOCl-NaBr-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO). The chemoselective oxidation at the primary alcohol groups was shown to be strongly pH dependent. Oxidation of
- Thaburet, Jean-Francois,Merbouh, Nabyl,Ibert, Mathias,Marsais, Francis,Queguiner, Guy
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- Enteric coating liquid
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An aqueous enteric coating liquid having a good dispersion stability and a good resistance to gastric juice comprising an alkali metal salt of an acid having a acid dissociation constant of at least 3 at 25° C. and a water-insoluble oxycarboxylic acid type cellulose derivative dispersed in water or a mixture of water and at most 20% by weight of a lower alcohol.
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