bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanismus der Cyclotrimerisierung von Phenylvinylketonen und die Kristallstrukturen von 1-((1R*,2S*,3R*,5S*)-und 1-((1R*,2S*,3R*,5R*)- 3.5-Dibenzoyl-2-hydroxy-2-phenylcyclohexylmethyl)-pyrrolidin-2-on/The Mechanism of Cyclotrimerisation of Phenylvinylketones and theCrystal Structures of 1-((1R*,2S*,3R*,5S*)-and1-((1R*,2S*,3R*,5R*)-3.5-Dibenzoyl-2-hydroxy-2-phenylcyclohexylmethyl)-pyrrolidin-2-on
Authors: Möhrle H. , Wille R. , Middelhauve B. , Mootz D. , Wunderlich H. 
Published: August 2018

Abstract
The cyclotrimerisation of 1-phenyl-2-propyn-1-ol (1) with pyrrolidin-2-one (2) to the tribenzoylcyclohexanes 4 and 5 produced -with modifications of the reaction conditions -the phenylvinylketone adducts 17 and 18 as intermediates and additionally the cyclohexylmethyl-pyrrolidin-2-ones 8 and 9. Obviously the mechanism consists of a primary attack of pyrrolidin-2-onat (2a) to a phenylketone (7) followed by a series of consecutive Michael reactions, which give rise to 4 and 5 as well as to 8 and 9. The latter two have been identified by X-ray crystal structure analyses. They crystallize in the monoclinic space group P21/c, Z=4, with 8: a = 1786,8(6), b = 636.7(2), c = 2280.9(8) pm, β = 102.33(3)°; 9: a = 1119.9(7), b = 1165.1(3), c = 2198.6(5) pm, β = 118.24(4)°.
Acyclo C-Nucleosides Analogues of Condensed 1,2,4-Triazines
Authors: El Ashry El Sayed H. , Rashed Nagwa , Hamid Hamida Abdel , Ramadan El Sayed 
Published: August 2018

Abstract
1-Acyclo C-nucleosides of 7-methyl-10H-1,2,4-triazolo[3’,4’:3,4][1,2,4]triazino[5,6-b]indoles (9) have been prepared by cyclodehydrogenation of the sugar derivatives of 3-hydrazino-8-methyl-5H-1,2,4-triazino[5,6-b]indole (1). The respective linear isomer as 4 has been prepared by a dehydrative cyclization of the amides of 1. Acetylation of the sugar hydrazones and their cyclized products gave the per-N,O-acetyl derivatives. The molecular connectivity of the products was established by 1H, 13C, and 2D H ,H Cosy spectra.
Darstellung und Kristallstruktur von P4O8 / Preparation and Crystal Structure of P4O8
Authors: Strojek Stephan , Jansen Martin 
Published: August 2018

Abstract P4O8 was synthesized for the first time in a pure state. Its crystal structure has been refined using X-ray diffractometer data (monoclinic, C2/c with a = 970.0(2); b = 1017.9(2); c = 692.3(1) pm; β = 96.95(2)°; V = 678.5 Å3; R1 = 0.033; wR2 = 0.073). Molecular geometry and packing in the solid state are discussed.
Darstellung, 11B-,13C-,1H-NMR- und Schwingungsspektren von Phenylundecahydro-closo-dodecaborat(2-) sowie Kristallstruktur von [As(C6H5)4]2[(C6H5)B12H11] / Preparation, 11B-, 13C-, 1H-NMR- and Vibrational Spectra of Phenylundecahydro-closo-dodecaborate(2-) and Crystal Structure of [As(C6H5)4]2[(C6H5)B12H11]
Authors: Koch T , Preetz W 
Published: August 2018

By reaction of [N(C4H9)4]2[B12H12] with chlorotriphenyltin at 170 °C the phenylundecahydro-closo-dodecaborate anion [(C6H5)B12H11]2- is formed which can be isolated by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose. The crystal structure of [As(C6H5)4]2[(C6H5)B12H11] has been determined by single crystal X-ray diffraction analysis; triclinic, space group P1̄ with a = 11,0066(11), b = 11.1371(6), c = 22.236(2) Å, α = 93.040(6), β = 92.981(8), γ = 100.254(6)°, Z = 2. The 11B NMR spectrum reveals the features (1:5:5:1) of a monosubstituated B12 cage with the ipso B atom at - 6.1 and the antipodal B at -17.4 ppm. The 13C and 1H NMR spectra show the characteristic patterns of the phenyl group. The IR and Raman spectra exhibit characteristic BH stretching vibrations between 2464 and 2519 cm-1 and the CC stretching vibrations in the range of 1405 to 1592 cm-1.
N-Boryl-Substituted Bis(amino)stannylenes and -plumbylenes
Authors: Wrackmeyer Bernd , Weidinger Jürgen 
Published: August 2018

Abstract Two equivalents of N-lithio-N-trimethylsilyl-amino-9-borabicyclo[3.3.1]nonane (1) react with tin and lead dichloride by salt elimination to give the corresponding bis(amino)stannylene 2 and -plumbylene 3, respectively. The compounds 2 and 3 are monomers in solution and were characterized by 1H, 13C, 14N, 29Si, 119Sn and 207Pb NMR spectroscopy.
Atomvolumen, Atomabstände und chemische Bindung in festen metallischen Elementen/Atomic Volume, Atomic Distances and Chemical Bonding in Solid Metallic Elements
Authors: Trömel Martin , Hübner Sven 
Published: August 2018

Abstract
Relationships between bond lengths and bond numbers and also between atomic volumes and valencies are derived and parameters for their calculation are given for the s-block, p-block, and d-block metals. From the atomic volumes under pressure, the valencies of three solid lanthanoids have been confirmed or redetermined: La 3; Ce 2. 3. and 4; Yb 2 and 3.
Magnetic Super-Exchange Mechanism and Crystal Structure of a Binuclear μ-Acetato-Bridged Copper(II) Complex of Pentadentate Binucleating Ligand.An Influence of Overlap Interactions to Magnetic Properties
Authors: Kavlakoglu Ebru , Elmali Ayhan , Elerman Yalçin 
Published: August 2018

Abstract
[Cu2(L)(O2CMe)· 1/2H2O (L = 1,3-bis (2-hydroxy-5-chlorosalicylideneamino)propan-2-ol) was synthesized and its crystal structure determined. (C19H16N2O5Cl2Cu2)· 1/2H2O, monoclinic, space group P 21/c, a = 20.660(10), b = 9.618(2), c = 21.810(10) Å3 , β = 109.3(8)­­°, V = 4090(2) Å3, Z = 8. The crystal contains two independent dicopper(II) complexes and an uncoordinated molecule of water in the asymmetric unit. In both molecules of the asymmetric unit, the two copper(II) ions are bridged by the alkoxo group of the ligand and by an acetato group. Magnetic susceptibilities of the complex in the solid state were measured over the temperature range 4.6 - 308 K. The title compound shows weak antiferromagnetic coupling with a best fit J value of -89.6 cm-1, which is interpreted in terms of a compensation effects of the different bridging ligands which participate in the super-exchange interactions. Ab initio restricted Hartree-Fock calculations have shown that the acetato bridge and the alkoxide bridge contribute to the magnetic interaction countercomplementarily to reduce antiferromagnetic interaction.
Palladium-Cadmium Ordering In Repdcd (Re = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb) And Comparison With Isotypic Indium Compounds
Authors: Fickenscher Thomas , Hoffmann Rolf-Dieter , Mishra Ratikanta , Pöttgen Rainer 
Published: August 2018

Abstract
Ternary intermetallic compoundsREPdCd (RE=La, Ce, Pr, Nd, Sm, Eu, Tb)were synthesized by reaction of the elements in sealed tantalum tubes in a high-frequency furnace. All compounds were investigated by X-ray diffraction on powders. Those with RE = La, Ce, Pr, Nd, Sm, and Tb contain trivalent rare earth metals and they crystallize with the hexagonal ZrNiAl type structure. NdPdCd [a = 764.8(3), c = 401.3(2) pm] and TbPdCd [a = 756.5(2), c = 389.0(1) pm] are reported here for the first time as well as EuPdCd. The compounds with La, Ce, Pr, and Sm [J. Alloys Compd. 182, 87 (1992)] are confirmed. The crystal structure of EuPdCd was refined from X-ray single crystal diffractometer data: TiNiSi type, Pnma, a = 745.9(3), b = 439.8(2), c = 863.7(3) pm, wR2 = 0.0405, 683 F2 values, and 20 variable parameters. The three-dimensional [PdCd] substructure consists of strongly puckered, orthorhombically distorted Pd3Cd3 hexagons with Pd-Cd distances ranging from 283 to 285 pm. The europium atoms fill the cavities within the [PdCd] network. Chemical bonding in the series REPdCd and REPdIn is compared.
Optically Active Cyclopentadienyl Ligands from the Chiral Pool, Part 1. The Synthetic Utility of a Camphor-Derived Pentafulvene
Authors: Quindt Valeri , Wallasch Mark , Wolmershäuser Gotthelf , Sitzmann Helmut 
Published: August 2018

Abstract
Starting from (1R)-(+)-camphor, the reaction with cyclopentadienylmagnesium chloride gave the corresponding tertiary alcohol 1, which was transformed into the optically active pentafulvene 5-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)cyclopentadiene (2) by acidcatalyzed water elimination. Deprotonation with tert-butyllithium yielded the corresponding lithium 5-{(1R)-1,7,7-trimethylbicyclo[2.2.1]hept-2-en-2-yl}cyclopentadienide (3), which was converted into the non-racemic 1,1β-bis{(1R)-1,7,7-trimethylbicyclo[2.2.1]hept-2-en-2- yl}ferrocene (4). 4 forms orthorhombic crystals of the space group P212121 with a = 7.7163(4), b = 10.7381(6), and c = 28.804(2) A˚ , which have been subjected to X-ray diffraction.
Crystal Structure of Tetrabutylammonium Carbonyltribromoplatinate(II) [(C4H9)4N][PtBr3(CO)]
Authors: Berkei Michael , Bickley Jamie F. , Heaton Brian T. 
Published: August 2018

Abstract
Tetrabutylammonium carbonyltribromoplatinate(II) [(C4H9)4N][PtBr3(CO)] crystallises in the monoclinic system in the space group P21/n with a = 1487.84(13), b = 897.41(8), c = 1849.6(2) pm, β = 106.558(2)° and four formula units per unit cell. The [PtBr3 (CO)]- anion is symmetrical (C2v) and almost planar with Pt-Br bond lengths of 242.40(12) pm (trans to CO), 243.25(10) pm and 242.99(9) pm (trans to Br), and a Pt-C bond length of 185.6(11) pm.
Die Koordination des [Hg2]2+-Kations in der konjugierten Supersäure HF/SbF5 durch CO oder H2O: Kristallstruktur von [Hg2(OH2)2][SbF6]2 · 4HF / The Co-ordination of the [Hg2]2+ Cation with CO or H2O in the Conjugated Super Acid HF/SbF5:Cryst al Structure of [Hg2 (OH2)2][SbF6]2 · 4HF
Authors: Berkei Michael , Schürmanna Markus , Bernhardt Eduard , Willner Helge 
Published: August 2018

Abstract
In the superacidic system HF/SbF5, the salt [Hg2(CO)2][Sb2F11]2 reacts with traces of water to give the novel salt bis(aqua)dimercury(I) bis(hexafluoroantimonate)tetra(hydrogenfluoride) solvate [Hg2(OH2)2][SbF6]2 · 4HF. It crystallises in the triclinic system in the space group P1̄ with a = 661.47(6), b = 695.11(7), c = 922.29(9) pm, α = 83.428(5)°, β = 84.186(6)°, γ = 71.696(5)°, and one formula unit per unit cell. The four heavy atoms of the [Hg2(OH2)2]2
+ cation are linked symmetrically and almost linear (nearly C2h) with a Hg-Hg bond length of 249.17(11) pm, two terminal Hg-O bonds of 214.8(8) pm, and an O-Hg-Hg bond angle of 177.6(3)°. Final R indices [I > 2σ(I)] are R1 = 0.0405 and wR2 = 0.0714.
Synthesis and Characterization of Tetraphenylphosphonium Tetraazidoborate
Authors: Fraenk Wolfgang , Nöth Heinrich , Klapötke Thomas M. , Suter Max 
Published: August 2018

Abstract
Tetraphenylphosphonium tetraazidoborate, [P(C6H5)4][B(N3)4], was obtained from B(N3)3 - in situ prepared from BH3 · O(C2H5)2 and HN3 - and [P(C6H5)4][N3]. Recrystallization from an acetonitrile / hexane mixture yielded colorless crystals in 60% yield. The molecular structurewas determined by single crystal X-ray diffraction and the [B(N3)4]- anionwas shown to possess S4 symmetry.
[3+1]-Cyclisierungen zu Tetraboraporphyrinogenen / [3+1]-Cycloadditions with Formation of Tetraboraporphyrinogenes
Authors: K¨ohler Thomas , Pritzkow Hans , Siebert Walter 
Published: August 2018

Abstract
2,5-Bis(chloro-2,2,6,6-tetramethylpiperidinoboryl)thiophene (1) and 2,5-bis(chloro-diisopropylaminoboryl) pyrrol (4) react with two equivalents of 2-lithiothiophenide to yield the corresponding 2,5-diborylheteroarenes (2,5) in which two boryl groups connect three heteroarenes. After lithiation of the terminal thiophenes of both compounds in 5,5'-position their reactions with the diborylthiophene 1 as well as with diborylpyrrol 4, lead to tetraboraporphyrinogenes (3, 6), the latter being the first tetraboratetraazaporphyrinogene. By silicon / boron exchange of 1-trimethylsilylimidazol with the 2,5-diborylpyrrol 4 the 2,5-bis(imidazolyldiisopropylamino- boryl)pyrrol 7 is formed, which reacts with BH3 and BEt3 to give the N-borane adducts of 7. The spectroscopic data and four X-ray structure analyses are reported.
Self-Assembly of Organo-Sulfur, Selenium and Tellurium Compounds via π-π-Stacking and Hydrogen Bonding Interactions
Authors: Kersting Berthold 
Published: August 2018

Abstract
The crystal structures of 2-isopropyl-benzisothiazol-3-one-7-carboxylicacid isopropyl amide and of the corresponding selenium and tellurium derivatives have been determined. In contrast to the sulfur and selenium compounds, the tellurium derivative has an unprecedented three-dimensional network structure held together via π-π stacking and hydrogen bonding interactions. The cavities in the 3D molecular network are filled with guestwater molecules that are hydrogen bonded to carbonyl oxygen atoms.
Synthesis and Reactivity of Bromo-Mer-Tricarbonyl-Trans-Bis[Tri(1-Cyclohepta- 2,4,6-Trienyl)Phosphane]-Manganese, Mnbr(CO)3[P(C7H7)3]2
Authors: Herberhold Max , Milius Wolfgang , Pfeifer Andreas 
Published: August 2018

Abstract
The reaction of Mn(X)(CO)5 (X = Cl, Br, I) with 2 equivalents of tri(1-cyclohepta-2,4,6- trienyl)phosphane, P(C7H7)3 ((1); [P] if coordinated to a metal) led stepwise first to cis- {Mn(X)(CO)4[P]} (X = Cl (4a), Br (4b), I (4c)) and then to mer,trans-{Mn(X)(CO)3[P]2} (X = Cl (5a), Br (5b), I (5c)). Nucleophilic displacement of the bromo ligand from (5b) by one-, threeor five-electron ligands gave the pseudohalide complexes mer,trans-{Mn(X)(CO)3[P]2} (X = NCO (5d) and NCS (5e)), the acetylacetonate derivative Mn(acac)(CO)2[P]2 (6) and the halfsandwich complexes CpMn(CO)2[P] (7) or TpMn(CO)3 (8). According to the X-ray structure determination of 5e the thiocyanate ligand is N-coordinated.
Synthesis, Thermal and X-Ray Investigations of the High-Temperature Phase of Copper(I) Cyanide
Authors: Reckeweg Olaf , Lind Cora , Simon Arndt , Salvo J. 
Published: August 2018

Abstract
CuCN was investigated by chemical analysis, IR spectroscopy and powder X-ray diffraction. A high-temperature phase of CuCN was identified and structurally characterized by Rietveld refinement. HT-CuCN is isotypic to AgCN (R3m (No. 166), Z = 3, a = 597.109(8), c = 484.33(5) pm, Cu (3a), C/N (6c), z = 0.3915(10) at 77 K) with head-tail disorder of the cyanide anions.
Synthesis of Microscale Particles of Ternary Sulphides via an Adjusted Polyol-Route
Authors: Blöß Stephan , Jansen Martin 
Published: August 2018

Abstract
The chalcocuprites Roquesite (CuInS2), Mohite (Cu2SnS3) and Famatinite (Cu3SbS4) have been synthesised from metal chlorides and thiourea in form of microscale particles via an adjusted polyolroute. The samples were characterised by means of SEM/EDX and XRD. The as prepared chalcocuprites were found to crystallise in metastable, cation disordered cubic structures. The particle sizes vary in the range of 0.2 to 3 micrometers. Thermal annealing transforms the samples into the thermodynamically stable polymorphs with ordered cationic substructures.
Investigations in the Systems Ag-Hg-X-O (X = AsV, SeIV, SeVI): Hydrothermal Single Crystal Growth of Ag3AsO4, AgHgI
2AsO4, AgHgIIAsO4, Ag2SeO4 and the Crystal Structure of Ag2HgII(SeO3)2
Authors: Weil Matthias 
Published: August 2018

Abstract
Single crystals of the already known phases Ag3AsO4, AgHgI
2AsO4, AgHgIIAsO4, Ag2SeO4 and of the hitherto unknown compound Ag2HgII(SeO3)2 were obtained under hydrothermal conditions (250 °C, 5d) from starting mixtures of the metal nitrates and the respective acids. Both Ag3AsO4 and AgHgI
2AsO4 are isotypic with the corresponding phosphates, Ag3PO4 and AgHgI
2PO4, whereas AgHgIIAsO4 and Ag2SeO4 crystallize in the thenardite (Na2SO4 (V)) structure. All crystal structures were refined by means of single crystal X-ray data. The crystal structure of Ag2HgII(SeO3)2 [Pbca, Z = 8, a = 6.8206(11), b = 11.237(3), c = 16.876(2) Å , 1677 structure factors, 101 parameters, R[F2 > 2σ (F2)] = 0.0193, wR(F2 all) =0.0394] consists of considerably distorted [AgO6] and [HgO6] octahedra, and trigonal SeIVO3 pyramids as the main building units. The [MO6] octahedra build a complex framework by sharing common edges and corners, and the SeIVO3 pyramids are located in the vacancies of this arrangement. The average Hg-O distance of 2.399 Å is significantly shorter than the average Ag-O distance of 2.551Å . The geometries of the two crysta̱llographically independent SeIVO3 pyramids are very similar and the average distance and angle (d(Se-O) = 1.709 Å , ∠(O-S-O) = 100.1°) lie in the characteristic range for a selenite(IV) group. A short comparative structural discussion between the various compounds obtained during the hydrothermal experiments is given.
Synthesis, Thermal Properties and Crystal Structure of Twinned Crystals of the New Coordination Polymer Poly[(CuBr)2(μ2-pyrimidine-N,N’)]
Authors: Näther Christian , Jeß Inke , Bolte Michael 
Published: August 2018

Abstract
Reaction of copper(I) bromide with pyrimidine in acetonitrile leads to the formation of crystals of the new coordination polymer poly[(CuBr)2(μ2-pyrimidine-N,N’)]. Indexing of the reflections yields a monoclinic primitive cell with a = 3.9119(2), b = 13.525(1), c = 15.346(1)Å , β = 97.29(1)° and V =805.4(1) Å3. Inspection of the reciprocal space shows weak reflections which might be indicative of a superstructure leading to a doubling of the crystallographic c-axis. The structure can be solved in space group P21/m but the refinement leads to very poor reliability factors (wR2 for all refl.: 62.57%, R1 for all Fo > 4σ (Fo) = 27.84%). A twin refinement assuming merohedral twinning drastically reduces the R-values (wR2 for all refl.: 7.27%, R1 for all Fo > 4σ (Fo) = 2.64%) and a structure model is obtained which consists of two crystallographically independent copper and bromine atoms and two pyrimidine ligands in the asymmetric unit. However, carefull inspection of this structure shows that the two crystallographically independent layers formed by the connection of the building blocks are very similar and that they are related by a translation by half of the crystallographic c-axis. As a result of that, the crystal is just a partial merohedral twin and the reflections which led to the assumption that the c-axis is twice as long are generated by the second twin domain. The structure was refined with the correct twin law (wR2 for all refl.: 6.70%, R1 for all Fo > 4σ (Fo) = 2.57%). By this procedure a reasonable structure model is obtained which consists of one crystallographically independent copper and bromine atom and one pyrimidine ligand. In the crystal structure CuBr double chains are formed which are connected into layers via μ-N,N’ coordination by the N-donor ligands. On heating, the compound loses all of the ligands and transforms into CuBr within only one single step in an exothermic reaction.
Ca10V5.2Fe0.8O24, a Novel Oxometalate with Discrete Complex Anions
Authors: Kleppa Kurt O. , Harringer Norbert A. , Preßlinger Hubert 
Published: August 2018

Abstract
Lustrous needle shaped prismatic single crystals of the new compound Ca10V5.2Fe0.8O24 were obtained out of a sample with nominal composition Ca2Fe1.6V0.4O5 prepared at 1400 °C. The crystals are opaque and stable to humid air. Ca10V5.2Fe0.8O24 crystallizes with a new structure type, space group Pnma with a = 6.803(3), b = 16.015(8), c = 10.418(7)Å , Z = 2, R = 0.041. The crystal structure is characterized by two mononuclear tetrahedral species, MO4, which differ significantly from each other with respect to their M-O bond lengths. One with an average bond distance of 1.709(8)Å represents an orthovanadate ion. The other with a significantly larger value d(M-O) = 1.744(6) Å corresponds to a mixed occupation of its centre according to [V0.8Fe0.2O4]3.5−. In the crystal structure the complex anions are arranged in separate sheets parallel to the (010) plane. They are separated from each other by three crystallographically independent Ca2+ ions which are each coordinated by 7 oxygen atoms in distorted pentagonal bipyramidal and trigonal prismatic configurations, respectively.
The Low-Temperature Polymorph of Tetramethyldiphosphinebis( monoborane): Insight into the Stabilization of Different Rotational Isomers in the Solid State
Authors: Müller Gerhard , Brand Jörg 
Published: August 2018

Abstract
The low-temperature (LT) polymorph of tetramethyldiphosphine-bis(monoborane), Me2(H3B)PP( BH3)Me2, was obtained by crystallization from diethyl ether at 4 °C. It crystallizes in the monoclinic space group P21/c, a = 6.464(1), b = 7.605(1), c = 11.867(2) Å , β = 119.99(1)° (at 153 K) with 2 molecules per unit cell. This implies that the individual molecules have crystallographic inversion symmetry and a strict anti arrangement with respect to the central B-P-P-B skeleton. At 87.6 °C (DTA) the LT polymorph transforms to the high-temperature (HT) modification which contains the anti and gauche conformers in a 1:2 ratio (P21/c, Z = 6; H. L. Carrell, J. Donohue, Acta Crystallogr. B24, 699 (1968)). This strongly suggests that the gauche conformer is higher in energy and stabilized by the crystal packing of the HT modification. The P-P-B angle in the anti LT form (113.91(6)°) ascertains the value of the anti conformer in the HT form (114.4(6)°) which was found to be significantly different from the gauche conformer which centered around 110 °C.
ScOH(CH3SO3)2, a Basic Methanesulfonate of Scandium with Chain Structure
Authors: Wickleder Mathias S. , Müller Ingrid 
Published: August 2018

Abstract
Single crystals of ScOH(CH3SO3)2 were obtained from a solution of Sc2(CO3)3 in methanesulfonic acid at pH 7. According to the X-ray single crystal structure determination, the compound crystallizes with the non-centrosymmetric orthorhombic space group Pmc21 (Z = 8, a = 743.92(8), b = 1497.7(3), c = 1540.1(2) pm, Rall = 0.0925) and contains the Sc3+ ions in octahedral coordination of oxygen atoms which belong to two OH− and four CH3SO3 − ions. The linkage of the Sc3+ ions leads to chains according to the formulation 1
∞[Sc(CH3SO3)4/2(OH)2/2] which are oriented along the [100] direction and connected via hydrogen bonds. The IR spectrum of the compound shows the typical bands of the CH3SO3 − ion.
Secondary Interactions in Gold(I) Complexes with Thione Ligands. 1. Three Ionic Chlorides
Authors: Friedrichsa Steffi , Jones Peter G. 
Published: August 2018

Abstract
Secondary interactions in the structures of [(etu)2Au]+Cl−.H2O (1), [(etu)2Au]+Cl− (2) and [(Me-etu)2Au]+Cl− (3) (etu = imidazolidine-2-thione) have been analysed. Within the cations, the torsion angle C-S...S-C is effectively the sole degree of freedom, and varies from almost eclipsed for 1 (−20°) via −79° for 2 to exactly 180° in 3. Both 1 and 2 form ten-membered rings in which the water molecule or the chloride ion respectively act as hydrogen bond acceptor to two NH donors of the cation. Further classical hydrogen bonds lead to the formation of double layer structures. Compound 3, in which the gold atom lies on an inversion centre and the chloride on a twofold axis, utilises its one N-H...Cl contact to form chains of hairpin bends, with Au...Cl contacts in the chain direction. Weak hydrogen bonds C-H...Cl and C-H...Au play at best a minor role in 1, but are more pronounced in 2 and 3.
Chemical Composition and Antitumor Activities from Givotia madagascariensis
Authors: Krebsa Hans C. , Duddeck Helmut , Malik Shahid , Beil Winfried , Rasoanaivo Philippe , Andrianarijaona Mamy 
Published: August 2018

Abstract
Two new erythroxylane diterpenes, named givotin A (1) and givotin B (2) were isolated from the bark of Givotia madagascariensis. Their structures have been established as 3α,12α-dihydroxy- 4(19),15-erythroxyladiene (1) and 3α-hydroxy-4(19),15-erythroxyladiene (2), respectively, on the basis of one and two-dimensional NMR spectroscopic studies (1H, 13C, COSY, HMQC, HMBC, NOESY, NOE difference spectra) as well as on mass spectral analysis. In addition six known compounds (3 - 8) have been isolated and identified. Cleistanthol (3), spruceanol (4) and 1,2- dihydroheudelotinol (5) demonstrated significant antitumor activities against three tumor cell lines (HM02, Hep G2, MCF7).