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201Author    Reinhold Tacke, Haryanto Linoh, MoayadT. Attar-Bashi, WilliamS. Sheldrick, Ludger Ernst, Roland Niedner, Joachim FrohneckeRequires cookie*
 Title    Sila-Pharmaka, 26. Mitt. [1] Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, III Sila-Pharmaca, 26th Communication [1] Preparation and Properties of Silicon Compounds with Potential Curare-Like Activity, III  
 Abstract    The potentially curare-hke silicon compounds 8a-Sf were synthesized and investigated with respect to their structure-activity relationships. The conformations of the com-pounds in the solid state and in solution were studied by X-ray diffraction analysis (8a-8e) and *H NMR spectroscopy (8a-8f), respectively. The muscle relaxing properties of 8a-8f were investigated on the mouse. The observed structure-activity relationships are not in accordance with the classical "14 A model" for neuromuscular blocking agents. Einführung 
  Reference    Z. Naturforsch. 37b, 1461—1471 (1982); eingegangen am 19. April 1982 
  Published    1982 
  Keywords    Silicon Compounds, Curare-Like Activity, X-ray, Conformational Analyses, Structure-Activity Relationships 
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 TEI-XML for    default:Reihe_B/37/ZNB-1982-37b-1461.pdf 
 Identifier    ZNB-1982-37b-1461 
 Volume    37 
202Author    Thomas Mack, Karl Peters, Hans-Georg Von SchneringRequires cookie*
 Title    Zur Stereochemie von Diazadien-Metall-Komplexen, V [1] Molekülstrukturen und CO-Kraftkonstanten nicht-starrer Chrom-, Molybdän- und Wolframcarbonylderivate DAD M(CO)3(*CO) (*C0 = 12 C0, 13 C0, C 18 0) Stereochemistry of Diazadiene Metal Complexes, V [lj Molecular Structures and CO Force Constants of Non-Rigid Chromium, Molybdenum and Tungsten Carbonyl Derivatives DAD M(CO)3(*CO) (*C0 = 12 CO, 13 C0, C 18 0) Heindirk torn Dieck  
 Abstract    Diazadiene metal tetracarbonyls, DAD M(CO)4, (M = Cr, Mo, W; DAD = R-N = CH-CH = NR with aliphatic and aromatic substituents R) show equi-distribution of one labelled CO when synthesized from fac-DAD M(CO)3(CH3CN) as a consequence of intramolecular CO site exchange. The structures of two Mo-complexes (1: R = iso-propyl; 2: R = 2,6-diisopropylphenyl) with DAD's of different bulkiness have been solved by X-ray methods. From the infrared solution spectra, including those of isotopically labelled (13 CO, C 18 0) compounds, all of the force constants ki, k2, ktt, kcc and kct bave been calculated independently. The ratios of interaction force constants deviate sharply from Cotton-Kraihanzel assumptions, perhaps because of the substantial deviation of the iraws-pair of CO groups from linearity (1: 154.5°, 2: 147.9°). The solid state N-Mo, Mo-C and C-0 bond lengths are neither in agreement with the generally accepted picture for donor/acceptor influences nor with typical IR data and force constant interpretations. (2 with higher v(CO) and ki, k2 has the longer CO bonds and shorter Mo-C bonds than 1.) The force constant sets have been used to calculate CO frequencies for over 60 labelled compounds with good accuracy (Av < 2 cm -1). 
  Reference    Z. Naturforsch. 38b, 568—579 (1983); eingegangen am 3. Dezember 1982 
  Published    1983 
  Keywords    Diazadiene Chromium, Molybdenum and Tungsten Carbonyls, X-Ray, Isotopically Labelled Carbonyls 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0568.pdf 
 Identifier    ZNB-1983-38b-0568 
 Volume    38 
203Author    M. Veith, 0. RecktenRequires cookie*
 Title    Cyclische Diazastannylene, XVIII [1] Zur Frage der Bindungsbeschreibung in Polyedern des Typs Sn4X3Y: Die Kristall-und Molekülstrukturen von Sn4(N Bu)4 und Sn4(N'Bu)30 Cyclic Diazastannylenes, XVIII [1] Bonding Description in Polyhedra of the Sn4X3Y-Type: The Crystal and Molecular Structures of Sn4(N'Bu)4 and Sn4(N<Bu)30  
 Abstract    Crystals of Sn4(N J Bu)4 (1) are monoclinic, space group P2i/c, with cell constants a = 1038.9(4), b = 1468.3(5), c = 1698.8(5) pm, ß = 91.6(1)° and Z = 4, while those of Sn4(N i Bu)30 (2) are triclinic, space group P I, with dimensions a = 1293.0(5), b = 1027.1(5), c = 1716.7(9) pm, a = 90.9(1), ß = 102.5(1), y = 107.0(1)° and Z = 4. The molecules 1 are held together by van-der-Waals forces, whereas two molecules 2 interact in the crystal by weak 0->-Sn donor bonds (290-332 pm) forming dimers. The outstanding structural elements of 1 and 2 are the Sn4N4 and Sn4N30 polyhedra, which can be described by two interpenetrating tetrahedra of tin atoms and of nitrogen or nitrogen and oxygen atoms forming a distorted cube, which approaches "43 m symmetry in the case of 1 and 3m for 2. Characteristic distances are in 1: Sn-N 220.2 pm, in 2: Sn-N 221.3 pm and Sn-0 213.2 pm. An almost ionic bonding model and two covalent models are discussed on the basis of the structural data including Sn4(N i Bu)3OAlMe3. 
  Reference    Z. Naturforsch. 38b, 1054—1061 (1983); eingegangen am 9. Juni 1983 
  Published    1983 
  Keywords    gewidmet Crystal Structure, Molecular Structure, Cubane-Like Polycycles, Bonding Description, X-Ray 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-1054.pdf 
 Identifier    ZNB-1983-38b-1054 
 Volume    38 
204Author    Pilar Souza, Luisa Sanz, Vicente Fernández, Agueda Arquero, Enrique Gutierrez, AngelesM. OngeRequires cookie*
 Title    Complexes of Zn, Cd and Hg Halides with S and N Polydentate Schiff-Base. Metal Template Effect in the Synthesis o f Analogous Oxygenated Base. Crystal Structure of [Zn(btsc)2Cl2l and [Cd(btsc)2Br2] M ontegancedo s/n, E-28660-Boadilla del M onte (Madrid), Spain  
 Abstract    Zinc, cadmiun and mercury dihalide react with 4-acetylpyridinthiosemicarbazone (4-aptsc) to give complexes with 1:1 and 2:1 ligand/m etal stoichiom etric ratios. These metals are effec­ tive templates for the Schiff-base condensation o f 4-acetylpyridine with semicarbazide to give the complexes [M (4-apsc)XJ and [M (4-apsc)2X 2] where M = Zn, Cd or Hg and X = Cl, Br or I. These com pounds were characterized by elemental analyses, conductivities measurements, IR and l3C, 'H N M R spectra. The zinc chloride and bromide com plexes o f benzalthiosem icarbazone (btsc) have been pre­ pared and characterized by X-ray measurements. The com pounds Zn(btsc)2Cl2 and Cd(btsc)2Br2 are isostructural and crystallize in the space group P 2j/«. The crystal structure o f the chlorine derivative has been resolved by single-crystal X-ray diffraction. The zinc centre is in a slightly distorted tetrahedral environment. There are intra and intermolecular hydrogen bonds. 
  Reference    Z. Naturforsch. 46b, 767 (1991); received June 27/O ctob er 22 1990 
  Published    1991 
  Keywords    4-Acetylpyridinthiosemicarbazone, 4-Acetylpyridinsemicarbazone, Benzalthiosemicarbazone, II-b-Metal Complexes, Crystal Structure, X -Ray 
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 TEI-XML for    default:Reihe_B/46/ZNB-1991-46b-0767.pdf 
 Identifier    ZNB-1991-46b-0767 
 Volume    46 
205Author    G. Ottfried Pawelke, Ralph Dammei, Wolfgang PollRequires cookie*
 Title    Darstellung von Difluormethanimin F2C = N H und F2C = N D durch Hydrolyse von CF3NCO Preparation of Difluoromethanimine F 2C = NH and F 2C = ND by Hydrolyses of C F 3NCO  
 Abstract    The title com pounds have been prepared by controlled hydrolysis o f C F 3NCO in N E t3. Their 13C, 19F and 'H N M R spectra are reported and their IR gas and IR matrix spectra are discussed in terms o f a normal coordinate analysis. The photoelectron spectrum o f F2C = NH is compared with those o f F2C = N F and H 2C = N H revealing a strong fluoro effect. In the solid state F2C = N H is aggregated to infinite zig-zag chains by N • • • H hydrogen bonding. 
  Reference    Z. Naturforsch. 47b, 351 (1992); eingegangen am 17. September 1991 
  Published    1992 
  Keywords    D ifluoromethanimine, N M R Spectra, Vibrational Spectra, Photoelectron Spectra, X-Ray 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0351.pdf 
 Identifier    ZNB-1992-47b-0351 
 Volume    47 
206Author    Max Herberhold, Guo-Xin Jin, ArnoldL. RheingoldRequires cookie*
 Title    Sulfurization and Selenization of the Halfsandwich Nitrosylmetal Complexes Cp*M(CO)2NO (M = Cr, Mo) and Cp*M(NO)I2 (M = Mo, W)  
 Abstract    The photo-induced decarbonylation o f Cp*Cr(CO)2NO in acetonitrile solution in the presence o f excess sulfur leads to the cjW o-pentasulfido complex Cp*Cr(NO)(S5) (1 a), while in 
  Reference    Z. Naturforsch. 48b, 1488—1498 (1993); received June 8 1993 
  Published    1993 
  Keywords    Sulfido Metal Complexes, Selenido M etal Complexes, Halfsandwich Nitrosylmetal Com pounds, X-Ray 
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 TEI-XML for    default:Reihe_B/48/ZNB-1993-48b-1488.pdf 
 Identifier    ZNB-1993-48b-1488 
 Volume    48 
207Author    F. P., J. M.Requires cookie*
 Title    (R, S) -Ethylenediamine -N,N'-disuccinato- cobaltate(III) Trihydrate  
  Reference    (Z. Naturforsch. 32b, 1089—1090 [1977]; received June 23 1977) 
  Published    1977 
  Keywords    X-ray, Crystal Structure, Cobalt(III) Complex, EDTA Isomer, Chelate Ring Conformation 
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 TEI-XML for    default:Reihe_B/32/ZNB-1977-32b-1089_n.pdf 
 Identifier    ZNB-1977-32b-1089_n 
 Volume    32 
208Author    Y. Sudhakara Babu, H. Manohar, K. Ramachandran, S. S. KrishnamurthyRequires cookie*
 Title    The Crystal Structure of a Spirocyclic Cyclophosphazene N3P3(NM e2)4(NHCH2CH2NH) -Evidence for Intermolecular Hydrogen Bonding  
  Reference    Z. Naturforsch. 33b, 588—589 (1978); received February 21 1978 
  Published    1978 
  Keywords    Tetrakis(dimethylamino)(ethylenediamino)cyclotriphosphazene, X-ray, Crystal Structure, Spirocyclic Structure, Envelope Conformation 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0588.pdf 
 Identifier    ZNB-1978-33b-0588 
 Volume    33 
209Author    Josef Ernst, WilliamS. Sheldrick, Jürgen-Hinrich FuhrhopRequires cookie*
 Title    Die Strukturen der essentiellen ungesättigten Fettsäuren, Kristallstruktur der Linolsäure sowie Hinweise auf die Kristallstrukturen der a-Linolensäure und der Arachidonsäure The Structures of the Essential Unsaturated Fatty Acids. Crystal Structure of Linoleic Acid and Evidence for the Crystal Structures of a-Linolenic Acid and Arachidonic Acid  
 Abstract    The essential fatty acids linoleic, a-linolenic and arachidonic acid have been crystallized for the first time. The crystal and molecular structures have been elucidated by X-ray analysis. Linoleic acid crystallizes monoclinic P2ijc with a = 4298(3), b — 463.2(3), c = 937.7(6) pm, ß = 109.38(8)°, Z = 4. The closely packed molecules are stretched with a ttttttsCssCstt conformation a . By comparison of the unit-cell constants and calculated densities of the unsaturated fatty acids it may be shown that both a-linolenic acid and arachidonic acid also possess stretched structures in the crystal lattice, a-linolenic acid must display a ttttttsCssCssCs and arachidonic acid a ttsCssCssCssCsttt conformation. Einleitung 
  Reference    Z. Naturforsch. 34b, 706—711 (1979); eingegangen am 15. Januar 1979 
  Published    1979 
  Keywords    Linoleic Acid, a-Linolenic Acid, Arachidonic Acid, Stretched Molecular Geometries, X-ray 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0706.pdf 
 Identifier    ZNB-1979-34b-0706 
 Volume    34 
210Author    Uwe Jürgens, Hans BrockmannRequires cookie*
 Title    Substituenteneinfiüsse auf die Geschwindigkeit der Photobilin-Bildung Substituent Effects upon the Rate of Photobilin Formation  
 Abstract    The structural requirements for the regioselective photochemical ring-opening of chlorin derivatives and the corresponding rate of formation of the pertinent photobilins are reported. The structure of one of the photobilins is verified by X-ray analysis. 
  Reference    Z. Naturforsch. 34b, 1026—1030 (1979); eingegangen am 30. März 1979 
  Published    1979 
  Keywords    Photooxidation, C-20-Substituted Chlorin Derivatives, Rate of Ring Cleavage, Structure, X-ray 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1026.pdf 
 Identifier    ZNB-1979-34b-1026 
 Volume    34 
211Author    P. C. Bharara, H. NöthRequires cookie*
 Title    Beiträge zur Chemie des Bors, CVII [1] Über Darstellung und Struktur eines tetraborylierten Hydrazins Contributions to the Chemistry of Boron, CVII [1] On the Preparation and Structure of a Tetraborylated Hydrazine  
  Reference    Z. Naturforsch. 34b, 1352—1357 (1979); eingegangen am 11. Juni 1979 
  Published    1979 
  Keywords    Tetrakis(l, 3-dimethyl-l, 3, 2-diazaborolidinyl)-hydrazin, NMR Spectra, X-ray 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1352.pdf 
 Identifier    ZNB-1979-34b-1352 
 Volume    34 
212Author    Friedrich-Wilhelm Grevels, Konrad Schneider, Carl Krüger, Richard GoddardRequires cookie*
 Title    Tricarbonyl(^ 4 -1.5-cümethylen-2.6-cümethylcyclooctan)eisen: photochemische Synthese und Struktur Tricarbonyl(^ 4 -l,5-dimethylene-2,6-dimethylcyclooctane)iron: Photochemical Synthesis and Structure  
 Abstract    Extended photolysis of pentacarbonyliron in neat 2,3-dimethylbutadiene results in dimerization of the diene and formation of tricarbonyl(?y 4 -l,5-dimethylene-2,6-dimethyl-cyclooctane)iron (1). The structure of complex 1 is characterized by a trigonal-bipyramidal geometry whereby the exocyclic double bonds of the diene ligand and one of the carbonyl groups lie exactly in the equatorial coordination plane. 
  Reference    Z. Naturforsch. 35b, 360—365 (1980); eingegangen am 5. November 1979 
  Published    1980 
  Keywords    Carbonyliron Olefin Complexes, Dimerization of Dimethylbutadiene, Photochemistry, NMR, X-ray 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-0360.pdf 
 Identifier    ZNB-1980-35b-0360 
 Volume    35 
213Author    Werner Winter, Hanspeter Bühl, Herbert MeierRequires cookie*
 Title    Structure Determination of 3,5-Biscyclohexylidene-l,2,4-trithiolane  
  Reference    Z. Naturforsch. 35b, 1015—1018 (1980); eingegangen am 14. März 1980 
  Published    1980 
  Keywords    Fragmentation of 1, 2, 3-Thiadiazoles, 1, 2, 4-Trithiolanes, X-ray 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-1015.pdf 
 Identifier    ZNB-1980-35b-1015 
 Volume    35 
214Author    Ekkehard Lindner, Günter Von AuRequires cookie*
 Title    Darstellung und Eigenschaften von und Reaktionen mit metallhaltigen Heterocyclen, VII [1] Heterolytische Spaltung der Re-Re-Bindung in den Zweikern-Anionen [(OC)4ReP(R2 )0] 2 2 ~ mit Elektrophilen - ein Weg zu Heterocyclen mit Re-C-o-Bindung Preparation and Properties of, and Reactions with, Metal-Containing Heterocycles, VII [1] Heterolytic Cleavage of the Re-Re Bond in the Binuclear Anions [(0C)4ReP(R2)0]2 2_ with Electrophiles -a Pathway to Heterocycles with Re-C a Bonds  
 Abstract    The preparation of the six-membered rhenacyclohexanes (OC)4ReP(R2)OCH2C(CH3)2CH2 (la, b) [R = CH3 (a), C6H5 (b)J is accomplished by heterolytic cleavage of the Re-Re bond in the binuclear anions [(0C)4ReP(R2)0]2 2 -with strong electrophiles like the alkane-diylbis(triflate) (CH3)2C(CH2Y)2 (Y= OSO2CF3), followed by an attack of the a>-positioned carbenium-like C atom on the phosphinite oxygen of the anion. 1 a, b insert SO2 under ring I I 
  Reference    Z. Naturforsch. 35b, 1104—1110 (1980); eingegangen am 9. Mai 1980 
  Published    1980 
  Keywords    Rhenacyclohexanes, Mechanism, S02-Insertio", X-ray, IR spectra, NMR spectra : 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-1104.pdf 
 Identifier    ZNB-1980-35b-1104 
 Volume    35 
215Author    M. Veith, 0. RecktenwaldRequires cookie*
 Title    Cyclische Diazastannylene, X [1] Die Kristall-und Molekülstruktur eines Moleküls mit verzerrt-würfelförmigem Sn4N30-Käfig Cyclic Diazastannylenes, X [1] The Crystal and Molecular Structure of a Molecule with a Distorted Cube-Shaped SiLiNsO-Cage  
 Abstract    The crystal and molecular structure of (me3CN)3(me3A10)Sn4 has been determined from three-dimensional X-ray data (4-circle diffractometer, R — 0.048). The crystals are mono-clinic, space group P2i/c, with cell dimensions a = 1017.4(5), b — 1488.5(7), c = 1748(1) pm, jS—91.5(1)° and Z — 4. The molecules approach 3m point-symmetry and include a SruNsO-cage, the atoms occupying the corners of a distorted cube formed by two, differently sized, interpenetrating concentric tetrahedra of tin and nitrogen/oxygen atoms. The nitrogen atoms are attached to tert-butyl groups, whereas the oxygen atom of the cage acts as a base towards the aluminiumtrimethyl group. Typical bond distances and angles (mean values) are: Sn-N = 219.9, Sn-0 = 220.3 pm; N-Sn-N = 81.2°; N-Sn-0 = 79.0°; Sn-N-Sn = 98.8° and Sn-O-Sn -100.2°. 
  Reference    Z. Naturforsch. 36b, 144—149 (1981); eingegangen am 14. Oktober 1980 
  Published    1981 
  Keywords    Molecular Tin(II) Compounds, Iminostannylenes, Cubane-Like Cage, X-ray, Molecular Structure 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0144.pdf 
 Identifier    ZNB-1981-36b-0144 
 Volume    36 
216Author    Lothar Weber, Dorothee Vehreschild-Yzermann, Carl Krüger+, Gotthelf Wolmershäuser+@bulletRequires cookie*
 Title    ÜbergangsmetaU-Schwefelylid-Komplexe, XI [1] Struktur und Reaktivität von ^ 5 -Thiacyclohexadienyl-l-oxid-chrom-KompIexeii Transition Metal Sulfur Ylide Complexes, XI [1] Structure and Reactivity of 77 5 -Thiacyclohexadienyl-l-oxide Complexes of Chromium  
 Abstract    The X-ray crystal and molecular structure of tetraethylammonium-tricarbonyl-(3,5-diphenylthiacyclohexadienyl-l-oxide)chromate has been determined. This organo-metallic anion can be nitrosylated to yield neutral [7y 5 -C5H3(C6H5)2SO](CO)2(NO)Cr. Further carbonyl displacement in this compound is achieved by treatment with pyridin or phos-phanes in the presence of triethylamineoxide. 
  Reference    Z. Naturforsch. 36b, 198—204 (1981); eingegangen am 4. September 1980 
  Published    1981 
  Keywords    X-ray, 3, 5-Diphenylthiacyclohexadienyl-l-oxide, Nit rosy lation, Amineoxide Assisted Carbonyl Displacement 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0198.pdf 
 Identifier    ZNB-1981-36b-0198 
 Volume    36 
217Author    Hartmut Köpf, Joachim PickardtRequires cookie*
 Title    Molekül-und Kristallstruktur von 1.1-Dimethylsilylentitanocendichlorid, (CH3)2Si(C5H4)2TiCl2 * Molecular and Crystal Structure of l,r-Dimethylsilylene Titanocene Dichloride, (CH3)2Si(C5H4)2TiCl2  
  Reference    Z. Naturforsch. 36b, 1208—1210 (1981); eingegangen am 4. Mai 1981 
  Published    1981 
  Keywords    [l]-Titanocenophane, l, l'-Dimethylsilylene Titanocene Dichloride, Molecular Structure, X-ray 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-1208.pdf 
 Identifier    ZNB-1981-36b-1208 
 Volume    36 
218Author    PeterM. Kaiser®, Reinhard Nesper, Karl-Friedrich Tebbe, Herbert Witzel»-Requires cookie*
 Title    Pyridin-4-on-Nueleosid + : Stabilisierung der Struktur im Kristall und in wäßriger Lösung Pyridine-4-on Nucleoside: Stabilisation of the Structure in the Crystal and in Aqueous Solution  
 Abstract    C10H13NO5 • H2O is monoclinic, space group P2i with a = 773.7 pm, b = 814.6 pm, c= 932.6 pm, ß = 109.36° at 143 K, Z = 2. The crystal structure has been refined to R =0.031 with 1340 counter reflections. Features of this nucleoside include an orientation of the base at the glycosidic bond N(l)-C(l') in the anii-range (52.5°), a ribosyl moiety in the C(2')-endo(S) conformation and in contrast to many other nucleosides a trans arrange-ment at C(4')-C(5'). This unusual conformation is stabilized by a distinct H-bonding scheme including the water molecule and the oxygen of the adjacent pyridin-4-on ring system. NMR data indicate on the other side that in solution the conformation of the nucleoside is anti/g + similar to that of other pyrimidine nucleosides. The 5'-OH group replaces the water molecule in the crystal. The preferred anti position of the base cannot be explained by an interaction of H(2,6) of the base with the 5'-OH group or the C(4) oxygen. Both protons which couple with H(3,5) coalesce in a single sharp doublet. Water entropy seems to be the decisive factor for the stabilization of the anti/g+ conformation in aqueous solution. 
  Reference    Z. Naturforsch. 36b, 1632—1639 (1981); eingegangen am 3. Juli 1981 
  Published    1981 
  Keywords    Pyridine-4-on Nucleoside, X-ray, NMR Spectra, Conformational Differences, Water Entropy 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-1632.pdf 
 Identifier    ZNB-1981-36b-1632 
 Volume    36 
219Author    R. Tacke, A. Bentlage, W. S. Sheldrick, L. Ernst, K. StoepelRequires cookie*
 Title    Sila-Pharmaka, 24. Mitt. [1] Sila-Analoga von Nifedipin-ähnlichen 4-Aryl-2.6-cümethyl-1.4-dihydropyridin- 3.5-dicarbonsäure-dialkylestern, II Sila-Drugs, 24 th Communication [1] Sila-Analogues of Nifedipine-Like Di alkyl 4-Aryl-2,6-dimethyl-l,4-dihydropyridine- 3,5-dicarboxylates, II  
 Abstract    In the course of systematic studies on sila-substituted drugs the nifedipine-like 1.4-di-hydropyridine derivatives 4 a, 4 b and 4 c were prepared and investigated with respect to sila-substitution effects. By X-ray diffraction analyses 4 a, 4 b and 4 c were found to be isostructural. The C/Si-analogues exhibit similar spasmolytic activities (in vitro, guinea pig ileum), comparable with that of nifedipine. However, the compounds differ sub-stantially in their in vivo activity, as measured by the antihypertensive effect on the renal-hypertensive rat. The experimental results are discussed with respect to the carbon/silicon exchange. 
  Reference    Z. Naturforsch. 37b, 443—450 (1982); eingegangen am 25. September 1981 
  Published    1982 
  Keywords    Sila-Analogues of Nifedipine Derivatives, X-ray, Pharmacological Activity, Structure-Activity Relationships 
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 TEI-XML for    default:Reihe_B/37/ZNB-1982-37b-0443.pdf 
 Identifier    ZNB-1982-37b-0443 
 Volume    37 
220Author    Horst Elias, Elke Hilms, Helmut PaulusRequires cookie*
 Title    X-Ray Structures and Spectral Properties of 4-Coordinate Copper(II) and Palladium(II) Complexes with a Tridentate ONN-Schiff Base Ligand  
 Abstract    The tridentate mono-basic Schiff base N-(2-diethylaminoethyl)salicylaldimine =Hsal-en-NEt2 forms complexes 1 = [(sal-en-NEt2)MY] with divalent metals M (Y = halide). The preparation of three copper(II) complexes la (Y = Br), lb (Y = Cl), and lc (Y = SCN) and one palladium(II) complex 1(1 (Y = Cl) is described and the UV/VIS spectra of these complexes in methanol and chloroform are compared and discussed. The crystals of la • CHCI3, lb • CHCI3, and Id • CHCI3 are all isotypic and crystallize in the ortho-rhombic space group Pbca, whereas the solvent-free crystals of 1 b (and also 1 a) are monoclinic with the space group P2i/c. The metal is 4-coordinate with an almost planar ONNY donor atom arrangement around the palladium and with a distorted arrangement around the copper. The crystals consist of separate non-bridged complex units and the chloroform is not coordinated. 
  Reference    Z. Naturforsch. 37b, 1266—1273 (1982); received March 31 1982 
  Published    1982 
  Keywords    X-ray, UV/VIS Spectra, Tridentate ONN Schiff Base, Copper(II) Complexes, Palladium(II) Complexes 
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 Identifier    ZNB-1982-37b-1266 
 Volume    37 
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