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dicarboxylic acid

Cai-Ping Ye, Gan Xu, Zheng Wang, Jie Han, Lian Xue, Fu-Yu Cao, Qi Zhang, Lin-Feng Yang, Li-Zhou Lin, Xu-Dong Chen
The functionalized ligand 9,10-anthraquinone-1,4-dicarboxylate acid (H2AQDC) was designed and synthesized in order to develop metal-organic coordination polymers as heterogeneous catalysts with a photosensitizing feature. Two major considerations of the ligand design are anthraquinone moieties for photosensitizing to harvest light and carboxylate groups for polymeric coordination toward less solubility. A series of transition metal complexes based on this ligand were synthesized subsequently, namely {Co(AQDC)(H2O)3·2H2O}n (Co-AQDC), {Ni(AQDC)(H2O)3·2H2O}n (Ni-AQDC), {[Cu(AQDC)(H2O)3][Cu(AQDC)(H2O)2(DMF)]·(H2O)4}n (Cu-AQDC), {Zn1...
April 25, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Yaxin Zi, Mingjin Zhu, Xinying Li, Yongbin Xu, Hao Wei, Defu Li, Changdao Mu
Dialdehyde-amyloses, dicarboxyl-amyloses and dialdehyde-carboxyl-amyloses with different oxidation levels were prepared and used to study the effects of aldehyde and carboxyl groups on the antibacterial activity of oxidized amyloses. The results showed that dicarboxyl-amyloses presented antibacterial activity through acidic pH effect produced by carboxyl groups, which was easily reduced or eliminated by adjusting pH. Dialdehyde-amyloses possessed a broad-spectrum antibacterial activity owing to the reactivity of aldehyde groups rather than acidic pH effect...
July 15, 2018: Carbohydrate Polymers
Abdel-Rahim S Ibrahim, Khaled M Elokely, Daneel Ferreira, Amany E Ragab
Biotransformation of fusidic acid ( 1 ) was accomplished using a battery of microorganisms including Cunninghamella echinulata NRRL 1382, which converted fusidic acid ( 1 ) into three new metabolites 2 ⁻ 4 and the known metabolite 5 . These metabolites were identified using 1D and 2D NMR and HRESI-FTMS data. Structural assignment of the compounds was supported via computation of ¹H- and 13 C-NMR chemical shifts. Compounds 2 and 3 were assigned as the 27-hydroxy and 26-hydroxy derivatives of fusidic acid, respectively...
April 21, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Zhiwei Chen, Xiuna Mi, Jing Lu, Suna Wang, Yunwu Li, Jianmin Dou, Dacheng Li
Three new luminescent transition coordination polymers, namely, {[Cd(L)(4,4-bpy)]·DMF·H2O}n (1), {[Cd2(L)2(bpe)2]·3DMF·2.5H2O}n (2), and {[Cd(L)(bibp)]·2DMF}n (3), (H2L = 4,4'-[benzene-1,3-diylbis(methanediylsulfanediyl)]dibenzoic acid, 4,4-bpy = 4,4-bipyridine, bpe = 1,2-bis(4-pyridyl)ethylene, and bibp = 4,4'-bis(benzoimidazo-1-ly)biphenyl), were solvothermally synthesized using Cd2+ ions and S-containing dicarboxylate acid in the presence of different N coligands. These complexes were fully characterized via elemental analysis, infrared spectroscopy (IR), single crystal X-ray diffraction analysis, and thermal gravimetric analysis (TGA)...
April 24, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Ana C D Pfluck, Dragana P C de Barros, Luís P Fonseca, Eduardo P Melo
The exploitation of an efficient enzymatic system to perform biopolymers synthesis, namely polyesters from dicarboxylic acids and dialcohols, requires the evaluation of the enzyme operational stability. This becomes particularly relevant when non-conventional media, such as miniemulsions, are used due to the inhomogeneity of the reaction media and presence of surfactants and high concentrations of organic compounds which might be deleterious to the structure-function of the enzyme. The stability of three lipases, Candida sp...
July 2018: Enzyme and Microbial Technology
Vsevolod A Bolotov, Konstantin A Kovalenko, Denis G Samsonenko, Xue Han, Xinran Zhang, Gemma L Smith, Laura McCormick, Simon J Teat, Sihai Yang, Matthew J Lennox, Alice Henley, Elena Besley, Vladimir P Fedin, Danil N Dybtsev, Martin Schröder
The complex [Zn2 (tdc)2 dabco] (H2 tdc = thiophene-2,5-dicarboxylic acid; dabco = 1,4-diazabicyclooctane) shows a remarkable increase in carbon dioxide (CO2 ) uptake and CO2 /dinitrogen (N2 ) selectivity compared to the nonthiophene analogue [Zn2 (bdc)2 dabco] (H2 bdc = benzene-1,4-dicarboxylic acid; terephthalic acid). CO2 adsorption at 1 bar for [Zn2 (tdc)2 dabco] is 67.4 cm3 ·g-1 (13.2 wt %) at 298 K and 153 cm3 ·g-1 (30.0 wt %) at 273 K. For [Zn2 (bdc)2 dabco], the equivalent values are 46 cm3 ·g-1 (9...
April 23, 2018: Inorganic Chemistry
Mohammed Jaoui, Michael Lewandowski, John H Offenberg, Kenneth S Docherty, Tadeusz E Kleindienst
Atmospheric oxidation of sesquiterpenes has been of considerable interest recently because of their likely contribution to ambient organic aerosol, but farnesene oxidation has been reported in only a few studies and with limited data. In the present study, a detailed chemical analysis of the organic fraction of gas and particle phases originating from the ozonolysis of a mixture of α-farnesene and β-farnesene was carried out in a 14.5 m3 smog chamber. More than 80 organic compounds bearing OH functionality were detected for the first time in this system in the gas and particle phases...
November 2017: Atmospheric Environment
Piotr Cysewski
The solubility advantage (SA) of meloxicam cocrystalized with mono- and dicarboxylic acids was expressed in terms of equilibrium constants involving active pharmaceutical ingredient and coformer in aqueous solutions. It is argued that SA can be quantified by concentration of pairs formed in water. The pH and concentration of dissolved components is included explicitly in the model. The alternative behavior of mono- and dicarboxylic acids was emphasized and addressed to different structural motifs. The structural and energetic properties of meloxicam and its complexes with carboxylic acids were characterized, including tautmerism and dissociation in aqueous media...
April 21, 2018: Journal of Molecular Modeling
Miriam Zacchia, Xuefei Tian, Enrica Zona, Robert J Alpern, Patricia A Preisig
Background Urine citrate is reabsorbed exclusively along the renal proximal tubule via the apical Na+ -dicarboxylate cotransporter NaDC-1. We previously showed that an acid load in vivo and media acidification in vitro increase NaDC-1 activity through endothelin-1 (ET-1)/endothelin B (ETB ) signaling. Here, we further examined the signaling pathway mediating acid-induced NaDC-1 activity. Methods We transiently transfected cultured opossum kidney cells, a model of the proximal tubule, with NaDC-1 and ETB and measured [14 C]-citrate uptake after media acidification under various experimental conditions, including inactivation of Pyk2 and c-Src, which were previously shown to be activated by media acidification...
April 20, 2018: Journal of the American Society of Nephrology: JASN
Kosuke Mori, Naofumi Kamimura, Eiji Masai
Sphingobium sp. strain SYK-6 expresses the best characterized catabolic systems for lignin-derived aromatic compounds. However, the uptake systems for these aromatics remain unknown. In this study, we identified and characterized the protocatechuate (PCA) transporter gene SLG_12880 (pcaK) in SYK-6. Sequence comparisons revealed that PcaK belongs to the aromatic acid/H+ symporter family of major facilitator superfamily transporters. Further, pcaK was highly conserved among Sphingomonadales possessing catabolic genes for vanillate and PCA...
April 19, 2018: Applied Microbiology and Biotechnology
Mei-Yan Gao, Xi Fan, Lei Zhang, Jian Zhang
A series of dicarboxylates bridged titanium-oxo clusters with {Ti3 (μ3 -O)} building units have been synthesized through facile one-step solvothermal reactions. It is interesting to find that the geometric characteristics of the obtained supramolecular structures highly depend on the configuration of the applied dicarboxylate ligands. A linear dimeric [Ti3 O]2 L2 complex can be constructed using flexible cyclohexanedicarboxylic acid, while the introduction of rigid 2-nitro-1,4-benzenedicarboxylic acid gives rise to a triangular [Ti3 O]3 L3 structure...
April 17, 2018: Inorganic Chemistry
Levi Kramer, Erome Hankore, Yilan Liu, Kun Liu, Esteban Jimenez, Jiantao Guo, Wei Niu
Carboxylic acid reductases (CARs) catalyze the reduction of a broad range of carboxylic acids into aldehydes, which can serve as common biosynthetic precursors to many industrial chemicals. This work presents a systematic biochemical characterization of five carboxylic acid reductases from different microorganisms, including two known and three new ones, using a panel of short-chain dicarboxylic acids and hydroxyacids, which are common cellular metabolites. All enzymes displayed broad substrate specificities...
April 16, 2018: Chembiochem: a European Journal of Chemical Biology
Tessily N Hogancamp, Frank M Raushel
Sphingobium sp. SYK-6 is a Gram-negative soil bacterium that contributes to the degradation of lignin. Lignin provides structural support and protection to plants as a complex aromatic heteropolymer. The lignin degradation pathway of guaiacyl moieties leads to the intermediate, protocatechuate (PCA), which is further degraded via the 4,5-cleavage pathway where PCA is ultimately metabolized to pyruvate and oxaloacetate. In this pathway, LigI has been shown to catalyze the hydrolysis of 2-pyrone-4,6-dicarboxylate (PDC) to (4E)-oxalomesaconate (OMA)...
April 16, 2018: Biochemistry
Chunhua Gong, Haiyang Guo, Xianghua Zeng, Hao Xu, Qingdao Zeng, Junyong Zhang, Jingli Xie
Two novel 3D Co(ii) metal-organic frameworks induced by flexible and rigid dicarboxylic acids [Co3(μ3-OH)(1,4-ttb)3(sa)]·3H2O (1) and Co2(μ3-OH)(1,4-ttb)(4,4'-bpdc) (2) (1,4-ttb = 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene, sa = succinic acid and 4,4'-bpdc = biphenyl-4,4'-dicarboxylic acid) have been successfully synthesized and characterized via X-ray single-crystal diffraction, powder X-ray diffraction (PXRD), FT-IR spectroscopy and TG analyses. In the structures of the compounds 1 and 2, the main ligand 1,4-ttb coordinates with Co(ii) ions to form 3D host frameworks with different cavities, and the auxiliary ligands sa and 4,4'-bpdc fill the 3D cavities...
April 9, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Brian N DiMarco, Ludovic Troian-Gautier, Renato N Sampaio, Gerald J Meyer
Two sensitizers, [Ru(bpy)2 (dcb)]2+ ( RuC ) and [Ru(bpy)2 (dpb)]2+ ( RuP ), where bpy is 2,2'-bipyridine, dcb is 4,4'-dicarboxylic acid-2,2'-bipyridine and dpb is 4,4'-diphosphonic acid-2,2'-bipyridine, were anchored to mesoporous TiO2 thin films and utilized to sensitize the reaction of TiO2 electrons with oxidized triphenylamines, TiO2 (e- ) + TPA+ → TiO2 + TPA, to visible light in CH3 CN electrolytes. A family of four symmetrically substituted triphenylamines (TPAs) with formal Eo (TPA+/0 ) reduction potentials that spanned a 0...
January 28, 2018: Chemical Science
Josy Augustine, Sofia Pavlou, Michael O'Hare, Kevin Harkin, Alan Stitt, Tim Curtis, Heping Xu, Mei Chen
Purpose: Müller glia are critical for the survival of retinal neurons and the integrity of retinal blood vessels. Müller glial cultures are important tools for investigating Müller glial pathophysiology. Here, we report a spontaneously immortalized Müller glial cell line originally cultured and subsequently cloned from mouse pups. The cell line, Queen's University Murine Müller glia Clone-1 (QMMuC-1), has been cultured for over 60 passages, has morphologic features like primary Müller cell (PMC) cultures and remains stable...
March 1, 2018: Investigative Ophthalmology & Visual Science
Mei Zhao, Dixuan Huang, Xiaojuan Zhang, Mattheos A G Koffas, Jingwen Zhou, Yu Deng
Adipic acid is an important dicarboxylic acid mainly used for the production of nylon 6-6 fibers and resins. Previous studies focused on the biological production of adipic acid directly from different substrates, resulting in low yields and titers. In this study, a five-step reverse adipate-degradation pathway (RADP) identified in Thermobifida fusca has been reconstructed in Escherichia coli BL21 (DE3). The resulting strain (Mad136) produced 0.3gL-1 adipic acid with a 11.1% theoretical yield in shaken flasks, and we confirmed that the step catalyzed by 5-carboxy-2-pentenoyl-CoA reductase (Tfu_1647) as the rate-limiting step of the RADP...
April 3, 2018: Metabolic Engineering
Rui Lu, Fang Lu, Xiaoqin Si, Huifang Jiang, Qianqian Huang, Weiqiang Yu, Xiangtao Kong, Jie Xu
Direct transformation of bio-based platform chemicals into aromatic dicarboxylic acids and their derivatives, which are widely used for the manufacture of polymers, is of significant importance for the sustainable development of plastic industry. However, limited successful chemical processes have been achieved. Here, we report a sustainable route for the production of phthalate and its hydrogenated derivative from bio-based malic acid and erythritol. The key Diels-Alder reaction is applied to build a substituted cyclohexene structure...
April 6, 2018: ChemSusChem
Yong-Liang Wei, Yue Li, Yun-Qi Chen, Ying Dong, Jia-Jia Yao, Xin-Yue Han, Yu-Bin Dong
A novel palladium N-heterocyclic bis-carbene dicarboxylate ligand (Pd-NHDC-H2 L) was successfully synthesized. In addition, an Pd-NHDC-containing UiO-67 type MOF (UiO-67-Pd-NHDC) was prepared on the basis of a size-matched ligand mixture of biphenyl-4,4'-dicarboxylic acid/Pd-NHDC-H2 L (9/1) and ZrCl4 under solvothermal conditions. The obtained UiO-67-Pd-NHC MOF can be a highly heterogeneous catalyst to promote Heck cross-coupling and intermolecular benzyne-benzyne-alkene insertion reactions.
April 4, 2018: Inorganic Chemistry
Wei-Ni Ma, Ming-Mei Zhou, Xiao-Jun Gou, Le Zhao, Fang Cen, Ying Xu, Hong-Yi Shen
The urinary metabolomic study based on gas chromatography-mass spectrometry (GC-MS) had been developed to investigate the possible antidepressant mechanism of chlorogenic acid (CGA) in a rat model of sleep deprivation (SD). According to pattern recognition analysis, there was a clear separation among big platform group (BP), sleep deprivation group (SD), and the CGA (model + CGA), and CGA group was much closer to the BP group by showing a tendency of recovering towards BP group. Thirty-six significantly changed metabolites related to antidepressant by CGA were identified and used to explore the potential mechanism...
2018: International Journal of Genomics
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