bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, Crystal Structures and Properties of Three New Tetrathiomolybdates with Organic Ammonium Cations
Authors: Srinivasan Bikshandarkoil R. , Dhuri Sunder N. , Poisot Martha , Näther Christian , Bensch Wolfgang 
Published: August 2018

Abstract
Three new tetrathiomolybdates (pipH2)[MoS4] (1), (trenH2)[MoS4]·H2O (2) and [(prop)4N]2- [MoS4] (3) (pip = piperazine, tren = tris(2-aminoethyl)amine and prop = n-propyl) were synthesized and characterized by elemental analysis, infrared spectroscopy, single crystal X-ray crystallography, and thermoanalysis. All compounds were prepared by the base promoted cation exchange method, i.e. by the reaction of the ammonium salt of [MoS4]2− with the corresponding organic amine or organic ammonium hydroxide. In the compounds 1 and 2 the organic amines pip and tren are diprotonated and they are linked to the tetrahedral [MoS4]2− dianions through weak hydrogen bonding interactions. The strength and number of these hydrogen bonds affect the Mo-S bond lengths and a relatively long Mo-S bond of 2.2114(8) Å is observed in 1 while the longest Mo-S bond in 2 is 2.1951(5) Å . In compound 3 no S···H-N interactions are possible and the Mo-S bond lengths scatter in a more narrow range compared to those in compounds 1 and 2. The thermal behavior was investigated using differential thermal analysis and thermogravimetry. On heating compound 1 decomposes in two closely related steps while 2 loses first the crystal water followed by the decomposition of the tetrathiomolybdate. The final products are amorphous molybdenum sulfides. The decomposition of compound 3 yields a very porous material with sponge-like morphology.
Secondary Interactions in Gold(I) Complexes with Thione Ligands, 3. Three Ionic Dimesylamides [1, 2]
Authors: Friedrichsa Friedrichsa , Jones Peter G. 
Published: August 2018

Abstract
Three structures of the form bis(thione)gold(I) di(methanesulfonyl)amide [thione = imidazolidine- 2-thione, 1; 1-methyl-imidazolidine-2-thione, 2; thiazolidine-2-thione, 3] were determined; all crystallize with one formula unit in the asymmetric unit. Each N-H hydrogen bond donor forms one classical two-centre hydrogen bond with an anion acceptor. Compound 1 thereby forms a complex layer structure with a layer thickness of 10.17 Å ; the packing may be analysed in terms of thinner subunit layers consisting of interlinked, hydrogen-bonded chains and rings. Compound 2 forms a chain structure consisting of a series of “hairpin bends”, a common feature in the gold complexes of 1-alkyl-imidazolidine-2-thiones. Compound 3 forms a corrugated ribbon structure in which the central region consists of parallel S-Au-S axes linked by aurophilic interactions; the anions exercise a “clamping” function by forming hydrogen bonds at the periphery of the ribbons. Further short contacts can be classed as weak hydrogen bonds C-H ··· X, with X = N, O, S or Au.
Synthesis and Structure of the Helicate (M)-(–)-[Pt2 {(R,R)-tetraphos}2](CF3SO3)4 · 4.5 H2O
Authors: Kitto Heather J. , Rae A. David , Willis Anthony C. , Zank Johann , Wild S. Bruce 
Published: August 2018

Abstract
The complex (M)-(-)-[Pt2{(R,R)-tetraphos}2](CF3SO3)4 · 4.5 H2O, where tetraphos = 1,1,4,7, 10,10-hexaphenyl-1,4,7,10-tetraphosphadecane, has been isolated and structurally characterized. The compound crystallizes in the space group C2 with two crystallographically different, but very similar, cations in the structure, each of which contains a 2-fold axis coincident with the crystallographic 2-fold axis. Each independent cation of the salt consists of a double-stranded, diplatinum(II) helicate that completes a ca. one-eighth turn of a double α-helix in the M direction, as evidenced by the angle between the two, non-orthogonal PtP4 square planes in each of the independent molecules. A feature of the structures is the 10-membered ring containing the two platinum atoms and the four chiral phosphorus stereocentres of R configuration; this ring has a distorted twist-boat-chair-boat conformation of λ helicity, which is responsible for the M twist of the helicate.
Trioxorhenium(VII) Complexes with Imidazolin-2-iminato Ligands
Authors: Tamm Matthias , Beer Stephan , Herdtweck Eberhardt 
Published: August 2018

Abstract
The Staudinger reaction of the N-heterocyclic carbenes 1,3-di-tert-butylimidazolin-2-ylidene (1a), 1,3-dimesitylimidazolin-2-ylidene (1b) and 1,3-diisopropyl-4,5-dimethylimidazolin-2- ylidene (1c) with trimethylsilyl azide in boiling toluene furnishes the corresponding 2- (trimethylsilylimino)imidazolines 2a - c. Treatment of Re2O7 with a twofold excess of these N-silylated imines results in the formation of the imidazolin-2-iminato trioxorhenium(VII) complexes 3a - c and hexamethyldisiloxane, Me3SiOSiMe3. The molecular structures of 2a, 3a and 3b are reported. In addition, the X-ray crystal structure determination of complex 3c · H2O is presented, which has formed by hydrolysis and cleavage of the metal-nitrogen bond in 3c. 3c · H2O consists of 2-aminoimidazolium cations and tetraoxorhenate(VII) anions, which are linked by N-H-O hydrogen bonds.
Pd(II) Complexes of N-Allyl Substituted N-Heterocyclic Carbenes
Authors: Hahn F. Ekkehardt , Heidrich Beate , Lügger Thomas , Pape Tania 
Published: August 2018

Abstract
The unsymmetrically substituted imidazolium salt 1-ethyl-3-allyl-imidazolium bromide 1 was synthesized by treatment of imidazole with one equivalent each of n-butyl lithium and ethyl bromide followed by treatment with one equivalent of allyl bromide. The symmetrically substituted derivatives 1,3-diallyl-imidazolium bromide 2 and 1,3-bis(3-methyl-2-butenyl)-imidazolium bromide 3 were obtained from imidazole and two equivalents of allyl bromide or 4-bromo-2-methyl-2-butenyl bromide, respectively, in the presence of sodium hydrogencarbonate as a base. The imidazolium bromides 1- 3 react with Pd(OAc)2 to afford the palladium(II) dicarbene complexes trans-[PdBr2(L)2] (L = 1- ethyl-3-allyl-imidazolin-2-ylidene, 4; L = 1,3-diallyl-imidazolin-2-ylidene, 5; L = 1,3-di(3-methyl-2- butenyl)imidazolin-2-ylidene, 6) by in situ deprotonation of the imidazolium salts. The X-ray structure analyses of 4- 6 show all three complexes to be mononuclear with palladium(II) coordinated in a square-planar fashion by two carbene and two bromo ligands.
Orthoamide, LXVII [1]. Bis(diformylamino)methan – ein neues leistungsfähiges Formylierungsmittel für aromatische Verbindungen / Orthoamides, LXVII [1]. Bis(diformylamino)methane – a New Efficient Formylating Reagent for Aromatic Compounds
Authors: Kantlehner Willi , Anders Ernst , Mezger Jochen , Stoyanov Edmont V. , Kreß Ralf , Wermann Kurt , Frey Wolfgang , Görls Helmar 
Published: August 2018

Abstract
Formaldehyde reacts with diformamide (10) to give N-(hydroxymethyl)diformamide (11), which upon treatment with thionylchloride yields N-(chlormethyl)diformamide (12) together with small amounts of oxydimethylenebis(diformamide) (13). Various diformylamine derivatives, such as diformylaminomethyl formiate (14), diformylaminomethylisothiocyanate (15) and the N-diformylaminomethylated guanidinium salt 16, can be prepared from 12. Bis(diformylamino) methane (7) can be obtained by the reaction of sodium diformamide (8) with either 1-(chloromethyl)pyridinium chloride (9) or N-(chloromethyl)diformamide (12) in acetonitrile. The action of tris(chloromethyl) amine (18) on sodium diformamide (8) affords tris(diformylaminomethyl)amine (19). The constitution of the compounds 7, 11 and 19 was confirmed by crystal structure determination. The nature of the products from the reactions of aromatic compounds with 12 depends on the Lewis acid which is used as activator. Thus the N-benzylformamides 20a, b can be obtained from toluene and mesitylene and 12/BF3-ether, whereas 1,2,4-trimethoxybenzene is formylated by 12/AlCl3 to give the aldehyde 22. Interestingly enough, a novel and efficient formylating reagent resulted from these investigations: bis(diformylamino)methane (7), which can be activated by Lewis acids, e. g. AlCl3. The scope of this procedure is comparable with that of the Olah-formylation method (formylfluoride/BF3).
Stereoselective Synthesis of Quinolizidine Alkaloids: (–)-Lasubin II
Authors: Weymann Markus , Kunz Horst 
Published: August 2018

Abstract
Based on a higly diastereoselective Mannich reaction of N-(3,4-dimethoxybenzylidene) 2,3,4,6- tetra-O-pivaloyl-β -D-galactopyranosylamine 3 with the Danishefsky diene the quinolizidine alkaloid lasubin II was synthesized in enantiomerically pure form in six steps.
A New Simple Method for the Preparation of Aryl Formates from Phenols
Authors: Hashmi Imran Ali , Kantlehner Willi , Ivanov Ivo C. 
Published: August 2018

Abstract
Aryl formates are prepared in a two step one-pot procedure from phenols. Firstly the formylating reagent triformamide (1b) is generated from sodium diformamide (2) and methanesulfonyl chloride in situ, which reacts with phenols 4a - f to give aryl formates 5a - f in good yields. Triformamide, prepared in situ, transforms anisole in the presence of aluminum chloride to the N-(diarylmethyl)formamide 7.
Structural and Electronic Properties of Zinc Blende-type Nitrides BxAl1–xN
Authors: Riane Rabah , Boussahla Zouaoui , Matar Samir F. , Zaoui Ali 
Published: August 2018

First principles total energy calculations were carried out to investigate structural and electronic properties of zinc blende-type AlN, BN and BxAl1−xN solid solutions. We have calculated the lattice parameters, bulk modulus, pressure derivative, and BxAl1−xN band-gap energy for zinc blende-type crystals of the compositions x = 0, 0.25, 0.5, 0.75, 1. The results show that the direct energy gap Γ15
V →Γ1
c shows a strong nonlinear dependence on the concentration x. For high boron contents
(x > 0.71), these materials have a phase transition from direct-gap semiconductors to indirect-gap semiconductors (Γ15
V → X1
c). This essential feature indicates that these materials should have very good optical properties at high concentrations of boron compared to those of AlN. Further discussions concern a comparison of our results with results obtained with other available theoretical and experimental methods.
A New Cyathane-xyloside from the Mycelia of Hericium erinaceum
Authors: Ma Bing-Ji , Zhou Yan , Li Lian-Zhen , Li He-Min , Gao Zhi-Ming , Ruan Yuan 
Published: August 2018

Abstract
A new cyathane-xyloside derivative, named erinacine R, was isolated from the mycelia of basidiomycete Hericium erinaceum. The structure of this compound was elucidated by spectral methods including 2D NMR experiments.
The Influence of the Amine Concentration onto Product Formation: Crystal Structures, Thermal Stability and Spectroscopic Properties of Two New Manganese Thiostannates Obtained under Solvothermal Conditions
Authors: Pienack Nicole , Näther Christian , Bensch Wolfgang 
Published: August 2018

Abstract
Two new thiostannates with Mn2+ ions were obtained under solvothermal conditions applying different amine concentrations. [Mn(C6H14N2)2(H2O)]2Sn2S6 (1) (C6H14N2 = 1,2-diaminocyclohexane, 1,2-dach) crystallizes in the monoclinic space group C2/c (with a = 23.7500(18), b = 15.5655(16), c = 12.1072(9) Å , β = 113.532(8)°, Z = 8). The second compound, [Mn(C6H14N2)2]- Sn2S6 ・2 C6H15N2 (2), crystallizes in the triclinic space group P¯1 with a = 7.3019(6), b = 11.1798(9), c = 13.2837(11) Å , α = 76.877(10), β = 74.719(9), γ = 82.972(10)°, Z = 1. Both structures feature [Sn2S6]4− anions acting as bidentate ligands and joining the octahedrally coordinated Mn2+ cations, but in 1 a molecular complex is formed, whereas in 2 a one-dimensional coordination polymer is observed. In 1 the Mn2+ cation has bonds to four N atoms of two 1,2-dach ligands, to one H2O molecule, and to one S atom of the [Sn2S6]4− anion. The [Sn2S6]4− anion is located on a center of inversion joining two symmetry related complexes. In 2 Mn2+ is surrounded by four N atoms of two 1,2-dach ligands and by two S atoms of two neighboring [Sn2S6]4− anions. In contrast to 1 a negatively charged coordination polymer is formed with [Sn2S6]4− anions acting as linkers and the Mn2+ centered complexes being the nodes. The co-crystallized 1,2-dach molecules are protonated, and they are located between the chains. The first compound was obtained from diluted aqueous solutions of 1,2-dach, and 2 crystallized from solutions containing < 25% H2O. In both compounds several short S···H distances indicate weak hydrogen bonding interactions. Compound 1 is stable up to 121 °C and 2 up to 220 °C. In the Raman spectra of 1 and 2 resonances which are typical for [Sn2S6]4− units could be observed. The band gaps are found to be 2.6 eV (477 nm) and 3.1 eV (400 nm) for 1 and 2, respectively.
Synthesis, Crystal Structure and Antitumor Study of an Iron(III) Complex of 2-Acetylpyrazine N(4)-Methylthiosemicarbazone
Authors: Zheng Lin Ping , Chen Chun Ling , Zhou Jing , Li Ming Xue , Wu Yan Juan 
Published: August 2018

Abstract
The title complex [Fe(C8H10N5S)2] · Cl has been synthesized from 2-acetylpyrazine N(4)-methylthiosemicarbazone and FeCl3 · 6H2O and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The complex consists of discrete monomeric molecules with octahedrally hexacoordinated iron(III) ions, in which two 2-acetylpyrazine 4-methylthiosemicarbazone units act as meridional NNS tridentate ligands coordinated to the central iron atom via the pyrazine nitrogen, azomethine nitrogen and sulfur atoms. Hydrogen bonds link the complex components to stabilize the crystal structure. The antitumor activity of the title complex was tested against K562 leucocythemia and BEL7402 liver cancer cell lines. The complex exhibits higher antitumor activity as compared to the free ligand.
1,2-Hydroboration of Alkyn-1-yldichlorosilanes using Triethylborane
Authors: Wrackmeyer Bernd , Khan Ezzat , Milius Wolfgang 
Published: August 2018

Abstract
Triethylborane, BEt3, can act as a 1,2-hydroborating reagent towards alkyn-1-ylsilanes, depending on the nature of the silane. A mechanism is proposed invoking hydrogen transfer from the β -carbon of one ethyl group, quite different from the 1,2-hydroboration mechanism using tri-n-propylborane, BnPr3. The structure of the products has been confirmed by comparison with that obtained using 9-borabicyclo[3.3.1]nonane, 9-BBN, as a well established 1,2-hydroborating reagent. All products have been characterized by a consistent set of NMR data (1H, 11B, 13C and 29Si NMR). The molecular structure of (Z)-1-dichlorosilyl-1-[9-(9-borabicyclo[3.3.1]nonyl)]-2-phenylethene has been determined by single crystal X-ray diffraction.
A Three-dimensional Manganese(II) 1,2,4-Benzenetricarboxylate Hydroxide Framework with Mn–O Inorganic Sheets: Hydrothermal Synthesis and Crystal Structure
Authors: Zhou Shuxi , Ke Yanxiong , Zou Hongliang , Liu Tianhua , Zhu Fang , Chen Jianmei , Xie Aijun 
Published: August 2018

Abstract
Utilizing unsymmetrical 1,2,4-benzenetricarboxylate (1,2,4-BTC) as a ligand, a complex [Mn2.5(1,2,4-BTC)- (OH)2(H2O)] was synthesized by hydrothermal reaction and characterized by single crystal X-ray diffraction. The coordination polymer crystallizes in the triclinic space group P1̅, with cell parameters a = 5.7702(5), b = 8.0269(6), c = 12.1378(9) Å, α = 88.000(1)°, β = 81.493(1)◦, γ = 88.569(1)°, and Z = 2. In the the crystal, there are Mn- O-Mn sheets which are further connected through the 1,2,4-BTC ligands into a 3D framework, which is rare in the coordination chemistry originating from transition metal ions and unsymmetrical polycarboxylates.
Photochemisch induzierte C–C-Verknüpfungen zwischen einem Mangan-koordinierten Pentadienylliganden und Acetylen
Authors: Koch Ernst-Christian , Reiss Guido J. 
Published: August 2018

Abstract
Irradiation of tricarbonyl(η5-2,4-dimethyl-2,4-pentadien-1-yl)manganese (1) in tetrahydrofuran (THF) at 208 K affords the carmine solvent complex dicarbonyl(η5-2,4-dimethyl-2,4-pentadien-1-yl)(THF)manganese (2). Complex 2 thermally reacts with acetylene (3) to give tricarbonyl(η3:2-1,3-dimethyl-bicyclo[3.3.1]-3,6-nonadien-2-yl)manganese (4) and dicarbonyl(5-7,10-13-η-6,8-dimethyl-1,3,5,8,10,12-tridecahexaen-5-yl)manganese (5). The crystal structure of complex 4 was determined at room temperature [triclinic space group

P

1
¯

,

$P\bar 1,$

a
=7.6891(9), b
=8.3860(8), c
=10.5252(13) Å, α
=93.000(9)°, β
=93.390(10)°, γ
= 108.032(8)°, V
=642.43(13) Å3]. The manganese atom is trigonal-bipyramidally coordinated by three carbonyl ligands, one ethenylic and one allylic fragment. Consequently, the bicyclic olefin ligand 1,3-dimethyl-bicyclo[3.3.1]-3,6-nonadiene coordinates the manganese atom in a η3:2 mode. The constitution of complex 5 was deduced from IR data, elemental analysis, and 1H NMR spectra. For the formation of complexes 4 and 5, a reaction mechanism is proposed.
Synthesis, characterization, and antitumor activity of some novel S-functionalized benzo[d]thiazole-2-thiol derivatives; regioselective coupling to the –SH group
Authors: Ramadan El Sayed , Abdel Hamid Hamida M. , Noureddin Sawsan A. , Badahdah Khadija O. 
Published: August 2018

Abstract
Several 2-substituted sulfanyl benzo[d]thiazoles were regioselectively synthesized by the reaction of benzo[d]thiazole-2-thiol (1a) with a variety of reagents under different basic conditions. Some 2-(2,3-disubstituted propyl sulfanyl)benzo[d]thiazoles were obtained from 2-(allylthio)benzo[d]thiazole, which was prepared by the allylation of 1a with allyl bromide in the presence of sodium hydride in dry N,N-dimethylformamide. Reaction of 1a with various pyrazolyl-quinoxaline derivatives was also investigated. Better yields and shorter reaction time were achieved for the synthesis of some derivatives by using ultrasound irradiation. The structural elucidation of all compounds was based on both analytical and spectroscopic data. The newly synthesized compounds were tested in vitro for their antitumor activity against Ehrlich ascites carcinoma (EAC) cells grown in albino mice. Doxorubicin was used as a standard antitumor antibiotic, and some compounds showed half maximal inhibitory concentration (IC50) in the range 40–68 μg mL−1.
Bakterienwand und Tumorinduktion durch Agrobacterium tumefaciens / Bacterial Cell Wall and Tumor Induction by Agrobacterium tumefaciens
Authors: Beiderbeck Rolf 
Published: August 2018

Bacterial cell walls are concerned with the tumor induction by Agrobacterium tumefaciens on leaves of Kalanchoe in two different ways: 1. If an inoculum of the virulent strain B6 of A. tumefaciens is mixed with cells of the avirulent strain IIBNV6 or with high concentrations of cell wall preparations from B6 itself tumor induction is inhibited. The same is true with cell wall preparations which were treated with ether or chloroform. In vitro growth of the bacteria is not influenced by cell wall preparations. 2. Penicillin inhibits tumor induction by inhibiting bacterial growth. Addition of penicillin as late as 8 hours after infection is still inhibiting tumor initiation. Growth of induced tumors is not inihited by penicillin.
The meaning of the two cell wall related processes in tumor induction is discussed.
Interaction of ʟ-Tryptophan with Inosine and Guanosine
Authors: Ibán̅ez I , Pieber M. , Tohá J. 
Published: August 2018

Abstract
The equilibrium constants for the complex between ʟ-tryptophan and inosine are established by solubility measurements at different temperatures, the order of magnitude of these constants being about 103 times bigger than the corresponding one for the formation of guanosine-tryptophan or any other of the nucleoside-tryptophan complexes. The mode of association of these molecules is governed mainly by stacking interactions as it has been suggested from previous PMR results. The differences in magnitude obtained for the equilibrium constants of (I + T) with respect to (G + T) are discussed in terms of differences in solute-solvent and solvent-solvent interactions. Thermodynamic parameters inferred from the equilibrium constants at different temperatures support this suggestion. Infrared results on I-T complex suggest that changes at the ribose moiety occurs and that possible hydrogen bridges are involved in the mechanism of association besides the stacking interactions.
Massenspektroskopische Untersuchungen an Glycosylglyceriden / Mass Spectrometric Investigation of Glycosyl Glycerides
Authors: Budzikiewicz H. , Rullkötter J. , Heinz E. 
Published: August 2018

Abstract
The mass spectrometric fragmentation behavior of glycosyl glycerides is discussed with special regard to the localisation of the fatty acids present in the molecule and to the applicability for mixture analyses.
Ein Zusammenhang zwischen Anregungszuständen von Molekülen und biologischer Wirkung, wie Strahlensensibilisierung und Kanzerogenität / A Correlation between the Properties of Excited States of Molecules and Biological Activity, as Radiosensibilization and Carcinogenic Activity
Authors: Popp Fritz A. 
Published: August 2018

Abstract
From the differences in electronic structure of 5-halogenated uracil derivatives and thymine there is discussed the connection with different radiosensibilization. At the same time the calculated energy change of the second and third excited singlet states for the particularly sensibilizating substances 5-bromo-uracil and 5-iodo-uracil compared with the remaining uracil derivatives is remarkable. In connection with different charge distribution this difference in principle may cause different energy transport processes. The very phenomenon is to be mentioned which has been discussed in previous papers dealing with the different carcinogenic molecules 3,4-benzpyrene and 1,2-benzpyrene.
Variable Content of a (GC) Rich Satellite DNA in Tumorous and Normal Cultures of Crepis capillaris
Authors: Sacristán Maria Dolores , Dobrigkeit Ingeborg 
Published: August 2018

Abstract
Analyses of DNA from tumorous and non tumorous cultures of Crepis capillaris by analytical equilibrium centrifugation in a neutral CsCl gradient revealed significant differences in regard to the content of a heavy component satellite, which was more highly represented in tumorous cultures. DNA of plant leaves showed a unimodal distribution of molecules. The choice of suitable controls served to demonstrate that the component satellite was not exclusive of tumorous tissues. The higher satellite content of tumorous cultures is probable related to their higher growth rate.
Landing Reaction of Musca domestica, IV: A. Monocular and Binocular Vision; B. Relationships between Landing and Optomotor Reactions
Authors: Taddei-Ferretti Cloe , de Talens Antonio Fernandez Perez 
Published: August 2018

Abstract
1. The behaviours of monocular and binocular flies are compared with respect to the landing reaction. It is found that landing reaction is elicited through different mechanisms by stimulating the zones of single or of double vision: Monocular stimulation in the field of single vision evokes reactions with both ipsilateral and contralateral leg s; monocular stimulation in the field of double vision evokes reaction only with the ipsilateral legs. 2. T he relationships between landing and optomotor reactions are analyzed. It is found that, a. W hen the fly is not free to turn itself, it may react to a lateral displacement in the visual field (optomotor stimulus) with a landing reaction ; b. The threshold for landing evoked by an expansion in the visual field (landing stimulus) is much low er than the threshold for landing evoked by a lateral displacement; c. A horizontal lateral displacement in the visual field of an eye is adequate to evoke the landing reaction only if it is perceived in the direction from the front to the back of the eye; d. W hen the fly is free to turn itself, it can present both landing and opto­motor reactions to a optomotor stimulus; e. W hen the fly is fixed at a point, landing reaction can be evoked also by an escape stimulus.