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31.
Rois Benassi Erika Ferrari Sandra Lazzari Francesca Pignedoli Ferdinando Spagnolo Monica Saladini 《Journal of Physical Organic Chemistry》2011,24(4):299-310
In the present study, we investigate the structures of glucosylated curcumin derivatives with DFT at B3LYP/6‐31G* level. A conformational analysis is performed in order to determine the conformational minimum (GS) and rotational transition state (TS) of curcumin derivatives and then their electronic features are evaluated. HOMO and LUMO frontier orbitals and maps of electron density potential (MEPs) are plotted and compared. In order to correlate their predicted spectroscopic properties with IR, UV–vis and NMR experimental data we extended the theoretical study on electronic properties to different solvents (H2O, MeOH, ACN, DMSO). The main finding is that the curcuminic core maintains the same geometrical and electronic structures in all compounds miming the metal coordination capability showed by curcumin. Therefore, we may confirm that the presence of glucose does not affect the electronic properties of the derivatives. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
32.
László Lázár Erika Mező Mihály Herczeg András Lipták Sándor Antus Anikó Borbás 《Tetrahedron》2012,68(36):7386-7399
A glucoronic acid-containing trisaccharide related to the antithrombin-binding DEFGH domain of heparin and its methanesulfonic acid analogues were synthesized. Trisaccharides without sulfonic acid content or possessing a sulfonatomethyl moiety at position 2 or 6 of unit F were prepared in high yields by [DE+F] couplings using the same disaccharide uronate donor, respectively. Synthesis of the trisaccharide with a 3-deoxy-3-sulfonatomethyl function was accomplished in three different pathways, from which a [D+EF] coupling and applying a non-oxidized precursor of the glucuronic acid afforded the trisaccharide in the highest yield. 相似文献
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Volckova E Evanics F Yang WW Bose RN 《Chemical communications (Cambridge, England)》2003,(10):1128-1129
The helix-turn-helix motifs of the DNA binding domains of human polymerase-alpha and polymerase-kappa are dramatically perturbed upon binding to cisplatin with concomitant release of zinc. 相似文献
36.
High-Quality Protein Crystal Growth of Mouse Lipocalin-Type Prostaglandin D Synthase in Microgravity
Inaka K Takahashi S Aritake K Tsurumura T Furubayashi N Yan B Hirota E Sano S Sato M Kobayashi T Yoshimura Y Tanaka H Urade Y 《Crystal growth & design》2011,11(6):2107-2111
Lipocalin-type prostaglandin (PG) D synthase (L-PGDS) catalyzes the isomerization of PGH(2) to PGD(2) and is involved in the regulation of pain and of nonrapid eye movement sleep and the differentiation of male genital organs and adipocytes, etc. L-PGDS is secreted into various body fluids and binds various lipophilic compounds with high affinities, acting also as an extracellular transporter. Mouse L-PGDS with a C65A mutation was previously crystallized with citrate or malonate as a precipitant, and the X-ray crystallographic structure was determined at 2.0 ? resolution. To obtain high-quality crystals, we tried, unsuccessfully, to crystallize the C65A mutant in microgravity under the same conditions used in the previous study. After further purifying the protein and changing the precipitant to polyethylene glycol (PEG) 8000, high-quality crystals were grown in microgravity. The precipitant solution was 40% (w/v) PEG 8000, 100 mM sodium chloride, and 100 mM HEPES-NaOH (pH 7.0). Crystals grew on board the International Space Station for 11 weeks in 2007, yielding single crystals of the wild-type L-PGDS and the C65A mutant, both of which diffracted at around 1.0 ? resolution. The crystal quality was markedly improved through the use of a high-viscosity precipitant solution in microgravity, in combination with the use of a highly purified protein. 相似文献
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As a novel extension, the Kabachnik–Fields reaction was applied to the synthesis of alkyl α‐aminomethyl‐phenylphosphinates, and the double phospha‐Mannich reaction was utilized in the preparation of bis(alkoxyphenylphosphinylmethyl)amines. A total of 27 new aminophosphinate derivatives were synthesized by the microwave‐assisted solvent‐free condensation of alkyl phenyl‐H‐phosphinates, paraformaldehyde, and primary or secondary amines. The starting P‐species were also prepared under microwave conditions. The formation of the N‐methylated aminomethyl‐phenylphosphinate by‐products was also investigated. 相似文献
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Leydi Erika Sarmiento Mildred Rodríguez Lorenzo Echevarria Vito Lubes 《Journal of solution chemistry》2010,39(10):1484-1491
The complex species formed between vanadium(III) and 1,10-phenanthroline (phen), 2,2′-bipyridine (bipy), and 8-hydroxyquinoline
(8hq) were studied in aqueous solution by means of electromotive forces measurements, emf(H), at 25 °C with 3.0 mol⋅dm−3 KCl as the ionic medium. The potentiometric data were analyzed using the least-squares computational program LETAGROP, taking
into account the hydrolytic vanadium(III) species formed in solution. Analysis of the vanadium(III)–phen system data shows
the formation of [VHL]4+, [V(OH)L]2+, [V2OL2]4+ and [V2OL4]4+ complexes. In the vanadium(III)–bipy system the [VHL]4+, [V(OH)L]2+, [V2OL2]4+ and [V2OL4]4+ complexes were observed, and in the vanadium(III)–8hq system the complexes [V(OH)L]+, [V(OH)2L], [VL2]+ and [VL3] were detected. 相似文献