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Xiaolin Lu, Yin Ding, Qiannan Niu, Shijie Xuan, Yan Yang, Yulong Jin, Huan Wang
INTRODUCTION: Different concentrations of parathyroid hormone [1-34] (PTH [1-34]) can have totally opposite effects on osteoblasts. Intermittent stimulation with PTH can significantly increase bone mineral density in vitro, mainly through the protein kinase A (PKA) signaling pathway, which phosphorylates runt-related transcription factor 2 (Runx2). The ClC-3 chloride channel, an important anion channel, can also promote osteogenesis via the Runx2 pathway based on recent studies. The purpose of our study, therefore, is to research whether the ClC-3 chloride channel has an effect on PTH osteodifferentiation in MC3T3-E1 cells...
2017: PloS One
Bo Qiao, Brandon E Hirsch, Semin Lee, Maren Pink, Chun-Hsing Chen, Bo W Laursen, Amar H Flood
The hierarchical assembly of colored cationic molecules with receptor-modified counteranions can be used to control optical properties in materials. However, our knowledge of when the optical properties emerge in the hierarchical organization and the variety of cation-anion salts that are available to create these materials is limited. In this work, we extend the salts from small halides to large inorganic anions and determine how the structure coevolves with the emission properties using solution assemblies...
April 24, 2017: Journal of the American Chemical Society
Guangfeng Liu, Jie Liu, Lina Nie, Rui Ban, Gerasimos S Armatas, Xutang Tao, Qichun Zhang
A zero-dimensional N,N'-dibutyl-4,4'-dipyridinium bromoplumbate, [BV]6[Pb9Br30], with unusual discrete [Pb9Br30](12-) anionic clusters was prepared via a facile surfactant-mediated solvothermal process. This bromoplumbate exhibits a narrower optical band gap relative to the congeneric one-dimensional viologen bromoplumbates.
April 24, 2017: Inorganic Chemistry
Guo-Yu Yang, Qi Wei, Shi-Jia Sun, Jie Zhang
Two novel alkali/alkaline-earth borates, Ba6[B6O9 (OH)6]2(H3BO3) (1) and Li7MAlB12O24 (M = Ba, Sr, Ca) (2a-c), with 1- and 3-D structures have been hydrothermally made and characterized. 1 features a rarely 1-D anionic chain built by hexaborate clusters of B6O11(OH)6 made of six BO4/ BO2(OH)2 tetrahedra. The anionic chains are embedded in the channels of Ba6-based wheel cluster open-framework. On the basis of the structural analyses of 1, by incorporating the rational Al atoms as the linkers and tuning the reaction conditions, the anhydrous borates 2a-c have been success-fully obtained, showing novel 3-D aluminoborates (ABOs) constructed from B6O14-based cluster chains and AlO6 octa-hedra...
April 24, 2017: Chemistry: a European Journal
Hao Zhang, Minmin Yang, Qian Luan, Hu Tang, Fenghong Huang, Xia Xiang, Chen Yang, Yuping Bao
Cellulose anionic hydrogels were successfully prepared from dissolving Tempo-oxidized cellulose nanofibers in NaOH/urea aqueous solution and then crosslinked with epichlorohydrin. The hydrogels exhibit microporous structure and high hydrophilicity, contribute to the excellent water absorption property. The growth indexes including the germination rate, root length, shoot length, fresh weight and dry weight of seedlings were investigated and the cellulose anionic hydrogel showed no significant difference compared with soil medium...
April 24, 2017: Journal of Agricultural and Food Chemistry
Yuekun Liu, Xuegang Liu, Gang Ye, Yang Song, Fei Liu, Xiaomei Huo, Jing Chen
Mesoporous silica/polymer hybrids with well-preserved mesoporosity were prepared by integrating the initiators for continuous activator regeneration (ICAR) atom transfer radical polymerization (ATRP) technique with the bio-inspired polydopamine (PDA) chemistry. By manipulating the auto-oxidative polymerization of dopamine, uniform PDA layers were deposited on the surfaces and pore walls of ordered mesoporous silicas (OMSs), thereby promoting the immobilization of ATRP initiators. Poly(glycidyl methacrylate) (PGMA) brushes were then grown from the OMSs by using the ICAR ATRP technique...
April 24, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Rongxin Nie, Steven Stark, Jindrich Symersky, Ronald S Kaplan, Min Lu
Integral membrane proteins of the divalent anion/Na(+) symporter (DASS) family translocate dicarboxylate, tricarboxylate or sulphate across cell membranes, typically by utilizing the preexisting Na(+) gradient. The molecular determinants for substrate recognition by DASS remain obscure, largely owing to the absence of any substrate-bound DASS structure. Here we present 2.8-Å resolution X-ray structures of VcINDY, a DASS from Vibrio cholerae that catalyses the co-transport of Na(+) and succinate. These structures portray the Na(+)-bound VcINDY in complexes with succinate and citrate, elucidating the binding sites for substrate and two Na(+) ions...
April 24, 2017: Nature Communications
Takeshi Uchida, Noriyuki Kobayashi, Souichiro Muneta, Koichiro Ishimori
CyaY is an iron transport protein for Fe-S cluster biosynthetic systems and a ferrochelatase that catalyzes insertion of Fe(2+) into protoporphyrin IX. Here, we found that CyaY has the ability to bind heme as well as iron, exhibiting a dissociation constant for heme of 21 ± 6 nM. Absorption and resonance Raman spectra revealed that both ferric and ferrous forms of heme were bound to an anionic ligand (e.g., tyrosine and/or cysteine). Consistent with this, mutagenesis studies showed that Tyr67 and Cys78 are possible heme ligands of CyaY...
April 24, 2017: Biochemistry
Hua Wu, Qian Wang, Jieping Zhu
We report an unprecedented organocatalytic enantioselective acyloin rearrangement of α,α-disubstituted α-hydroxy acetals. In the presence of a catalytic amount of chiral binol-derived N-triflyl phosphoramide, α-hydroxy acetals rearranged to α-alkoxy ketones in good to high yields with high enantioselectivities. Formation of an ion pair between the in situ generated oxocarbenium ion and the chiral phosphoramide anion was proposed to be responsible for the highly efficient transfer of chirality. Conditions for removal of cyclohexyl and cyclopentyl groups from the corresponding α-alkoxy ketones were uncovered underpinning their potential general utility as hydroxy protecting groups...
April 24, 2017: Angewandte Chemie
Ivelina Georgieva, Adelia J A Aquino, Natasha Trendafilova, Hans Lischka
Semi-classical ab initio simulations of the absorption spectra of neutral and anionic p-hydroxybenzylidene-2,3-dimethylimidazolinone (p-HBDI), a model chromophore of Green Fluorescent Protein (GFP) and of a positively charged neutral (N+)-HBDI chromophore model were performed in gas phase with the resolution-of-identity algebraic diagrammatic construction through second-order (RI-ADC(2)) method. The calculated absorption spectra in gas phase are composed of one band centered at 3.51 eV (HBDI), 2.50 eV (HBDI(-) ) and 3...
April 24, 2017: Photochemistry and Photobiology
Marco Campetella, Maria Montagna, Lorenzo Gontrani, Eleonora Scarpellini, Enrico Bodo
We have explored by means of ab initio molecular dynamics two ionic liquids based on the combination of a choline cation with deprotonated cysteine and aspartic acid anions. While the combination of the strong base choline with various other amino-acids leads to the formation of a highly ionized medium where proton transfer is negligible, the presence of additional protic functions on the SH and COOH groups leads to an unexpected and interesting behavior and to a sizable migration of their acidic protons onto the NH2 basic terminals...
April 24, 2017: Physical Chemistry Chemical Physics: PCCP
Kamil Paduszyński
This paper reports a comprehensive evaluation of the conductor-like screening model for real solvents (COSMO-RS) in predicting infinite dilution activity coefficients (γ(∞)) of molecular solutes in ionic liquids (ILs). In particular, comparative analysis of two quantum chemical levels of calculations used in the COSMO part of COSMO-RS, namely, TZVP-COSMO and TZVPD-FINE, is presented and discussed. The final assessment of the model performance is established based on a comparison of its predictions with the experimental data pool consisting of 41 868 data points extracted form 182 references, covering 233 ILs (including salts belonging to 12 different cationic families) and 150 molecular solutes (including a great variety of non-polar, polar and self-associating organic compounds and water) combined with 8554 distinct binary systems...
April 24, 2017: Physical Chemistry Chemical Physics: PCCP
Stefan Suckert, Julia Werner, Inke Jess, Christian Näther
The crystal structure of the title compound, [Co(NCS)2(C12H9NO)2(CH3OH)2], consists of cobalt(II) cations that are octa-hedrally coordinated by two N-terminal bonding thio-cyanato anions, two methanol mol-ecules and two 4-benzoyl-pyridine ligands into discrete complexes that are located on centres of inversion. These complexes are further linked by O-H⋯O hydrogen bonding between the hy-droxy H atom of the methanol ligand and the carbonyl O atom of the 4-benzoyl-pyridine ligand of a neighboring complex into layers parallel to (101)...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Keisuke Kai, Tomohiko Hamaguchi, Isao Ando
The title salt, [Ni(C3H2NS2)(C12H8N2)2]PF6·1.5C4H8O2, was the unexpected product on making an attempt to prepare an [Ni(2-mercapto-thia-zol-ate)(1,10-phenanthroline)](+) complex by reaction of [NiCl2(1,10-phen-an-throline)] with 2-mercapto-thia-zolate. In the resulting complex, the 2-mercapto-thia-zolate anion acts as a chelating ligand, which coordinates to the Ni(II) ion with the thia-zolyl N and thiol-ate S atoms. In the crystal, π-π stacking inter-actions between the coordinating 1,10-phenanthroline mol-ecules of adjacent complexes result in a zigzag chain running parallel to the c axis...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Nina Salamzadeh, Zeynep Demircioglu, Ufuk Korkmaz, Orhan Büyükgüngör
The asymmetric unit of the title compound, C6H10N2(2+)·2C4HO4(-), comprises two hydrogen squarate (Hsq(-); systematic name: 2-hy-droxy-3,4-dioxo-cyclo-butano-late) anions and a 2-(aza-niumylmeth-yl)pyridinium dication. The squaric acid mol-ecules each donate an H atom to the N atoms of the pyridine ring and the amino-methyl units of a 2-(amino-meth-yl)pyridine mol-ecule, forming the 1:2 salt. The Hsq(-) anions are linked by strong O-H⋯O hydrogen bonds and an N-H⋯O hydrogen bond links the 2-(aza-niumylmeth-yl)pyridinium cation to one of the squaric acid anions...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
James L Wardell, Mukesh M Jotani, Edward R T Tiekink
In the anion of the title salt hydrate, H5N2(+)·C7H5N2O4(-)·2H2O, the carboxyl-ate and nitro groups lie out of the plane of the benzene ring to which they are bound [dihedral angles = 18.80 (10) and 8.04 (9)°, respectively], and as these groups are conrotatory, the dihedral angle between them is 26.73 (15)°. An intra-molecular amino-N-H⋯O(carboxyl-ate) hydrogen bond is noted. The main feature of the crystal packing is the formation of a supra-molecular chain along the b axis, with a zigzag topology, sustained by charge-assisted water-O-H⋯O(carboxyl-ate) hydrogen bonds and comprising alternating twelve-membered {⋯OCO⋯HOH}2 and eight-membered {⋯O⋯HOH}2 synthons...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Andrey A Petrov, Eugene A Goodilin, Alexey B Tarasov, Vladimir A Lazarenko, Pavel V Dorovatovskii, Victor N Khrustalev
At a temperature of 100 K, CH5N2(+)·I(-) (I), crystallizes in the monoclinic space group P21/c. The formamidinium cation adopts a planar symmetrical structure [the r.m.s. deviation is 0.002 Å, and the C-N bond lengths are 1.301 (7) and 1.309 (8) Å]. The iodide anion does not lie within the cation plane, but deviates from it by 0.643 (10) Å. The cation and anion of I form a tight ionic pair by a strong N-H⋯I hydrogen bond. In the crystal of I, the tight ionic pairs form hydrogen-bonded zigzag-like chains propagating toward [20-1] via strong N-H⋯I hydrogen bonds...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Varsha Rani, Harkesh B Singh, Ray J Butcher
In the title salt, (C34H44N4)[HgCl4], the [C34H44N4](2+) cations and [HgCl4](2-) anions are linked by N-H⋯Cl hydrogen bonds. One of the two n-pentyl side chains was refined as disordered over two sets of sites, with occupancies of 0.733 (18) and 0.267 (18). The geometry around the Hg(II) atom in the [HgCl4](2-) anion is distorted tetra-hedral, with bond angles ranging from 98.16 (3) to 120.68 (3)°. In the [HgCl4](2-) anion, there are two short Hg-Cl bonds [2.4120 (9) and 2.4171 (11) Å], one inter-mediate Hg-Cl bond [2...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Rajendhraprasad Tatikonda, Matti Haukka
Two ruthenium carbonyl complexes with the 4'-chloro-2,2':6',2''-terpyridine ligand (tpy-Cl, C15H10ClN3), i.e. [RuCl(tpy-Cl)(CO)2][RuCl3(CO)3] (I) [systematic name: cis-di-carbonyl-chlorido(4'-chloro-2,2':6',2''-terpyridine-κ(3)N)ruthenium(II) fac-tricarbonyltri-chlorido-ruthenate(II)], and [RuCl2(tpy-Cl)(CO)2] (II) [cis-dicarbonyl-trans-di-chlorido(4'-chloro-2,2':6',2''-terpyridine-κ(2)N(1),N(1'))ruthenium(II)], were synthesized and characterized by single-crystal X-ray diffraction. The Ru(II) atoms in both centrosymmetric structures (I) and (II) display similar, slightly distorted octa-hedral coordination spheres...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Dilovan S Cati, Helen Stoeckli-Evans
The reaction of silver(I) nitrate with the mono-substituted pyrazine carboxamide ligand, N-(pyridin-2-ylmeth-yl)pyrazine-2-carboxamide (L), led to the formation of the title compound with a metal-organic framework (MOF) structure, [Ag(C11H10N4O)(NO3)] n , poly[μ-nitrato-[μ-N-(pyridin-2-ylmethyl-κN)pyrazine-2-carboxamide-κN(4)]silver(I)]. The silver(I) atom is coordinated by a pyrazine N atom, a pyridine N atom, and two O atoms of two symmetry-related nitrate anions. It has a fourfold N2O2 coordination sphere, which can be described as distorted trigonal-pyramidal...
April 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
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