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1Author    W. J. Stec, R. Kinas, A. OkruszekRequires cookie*
 Title    Configurational Assignments to 2-X-2-Y-4-methyl-l,3,2-dioxaphosphorinans  
  Reference    (Z. Naturforsch. 31b, 393—395 [1976]; received July 17 1975) 
  Published    1976 
  Keywords    Dioxaphosphorinans, Configuration, Conformation 
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 TEI-XML for    default:Reihe_B/31/ZNB-1976-31b-0393_n.pdf 
 Identifier    ZNB-1976-31b-0393_n 
 Volume    31 
2Author    F. Fehér, B. EngelenRequires cookie*
 Title    Beiträge zur Chemie des Schwefels, 116 [1] Kristall-und Molekülstrukturen von und 3-Methyl- Contributions to the Chemistry of Sulfur, 116 [1] Crystal and Molecular Structures of 1,2,4,5-Benzotetrathiepine and 3-Methyl-1,2,4,5-benzotetrathi  
 Abstract    The structures of 1,2,4,5-benzotetrathiepine and 3-methyl-l,2,4,5-benzotetrathiepine were determined by X-ray structure analysis. The constitution of the molecules, which was proposed by way of spectroscopic data, could be verified. The conformation of the seven-membered rings is the chair form. The position of the methyl group in 3-methyl-1,2,4,5-benzotetrathiepine is equatorial with respect to the seven-membered ring. Details of the conformations are discussed. Bond distances and angles are compared with those in other molecules, which have similar structures. 
  Reference    Z. Naturforsch. 34b, 426—430 (1979); eingegangen am 18. Oktober 1978 
  Published    1979 
  Keywords    X-ray, Cyclosulfanes, Conformation 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0426.pdf 
 Identifier    ZNB-1979-34b-0426 
 Volume    34 
3Author    Martin DrägerRequires cookie*
 Title    5-Chlor-5-phenyl-l-oxa-4.6-dithia-5-stannocan, ein diplanarer Übergangszustand bei der Racemisierung der Wanne-Sessel- Konformation in einem 8-Ring [1] 5-Chloro-5-phenyl-l-oxa-4,6-dithia-5-stannocane, a Diplanar Transition State for the Racemisation of the Boat-Chair Conformation in an Eight-Membered Ring [1]  
 Abstract    The title compound has been synthesized from PhSnCl3 and the disodium salt of bis(2-mercaptoethyl)ether. The crystal structure has been determined and refined to R — 0.033. The conformation of the eight-membered heterocycle is slightly disordered and represents a diplanar form, which is generally considered the transition state near the saddle point of the energy surface between the two enantiomers of the boat-chair con-formation. The configuration around tin is a trigonal bipyramid with equatorial sulfur atoms, an equatorial phenyl group and with axial atoms CI and O (transannular distance Sn--0 241 pm). 
  Reference    Z. Naturforsch. 36b, 437—440 (1981); eingegangen am 4. Februar 1980 
  Published    1981 
  Keywords    Tin, Heterocycles, Conformation, Transition State 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0437.pdf 
 Identifier    ZNB-1981-36b-0437 
 Volume    36 
4Author    Alfred Gieren, Viktor Lamm, Dieter Oesterhelt, Hans-Jörg SchludeRequires cookie*
 Title    Röntgenstrukturanalyse des 4-Keto-a//-*rcms-retinals X-ray Structure Analysis of the 4-Keto-aW-/rafts-retinal  
 Abstract    The title compound (C20H26Ü2) crystallizes in the monoclinic space group P2i/n with a = 14.761(2), 6 = 8.292(1), c = 15.210(2) Ä, /S= 102.40(1)°; Z = 4. The structure was solved by direct methods and refined by least squares to a final R-value of 0.038 for 1211 observed reflections. The crystal structure is isomorphous with that of all-trans-retinal. The cyclohexenone ring shows a half-boat conformation. The connection of the cyclo-hexenone ring and the conjugated polyene chain via a formal single C-C bond is s-cis. The torsion angle C(5)-C(6)-C(7)-C(8) amounts to 56°. For the polyene side chain the typical curvature is evident. A comparison with analogous compounds shows that details in conformation, especially at the ring side-chain connection, are induced by crystal matrix. It seems that the differences in biological activity between retinal analogous compounds are not reflected by conformational differences of the free molecules. 
  Reference    Z. Naturforsch. 37b, 1612—1622 (1982); eingegangen am 1. Juni 1982 
  Published    1982 
  Keywords    N-ray, Retinal, Conformation 
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 TEI-XML for    default:Reihe_B/37/ZNB-1982-37b-1612.pdf 
 Identifier    ZNB-1982-37b-1612 
 Volume    37 
5Author    Gabi Reber, Jürgen Riede, Gerhard MüllerRequires cookie*
 Title    Molecular Structure of (o-Trimethylsilyl- benzyl)diphenylphosphine  
 Abstract    (o-Trimethylsilylbenzyl)diphenylphosphine (1) crystallizes in the monoclinic space group P2 Jn with a = 14.088(2), b = 8.712(1), c = 16.481(2)Ä, ß = 101.63(1)°, V -1981.3Ä\ Z = 4. There is no P-Si interaction in the solid state which is also found for the solution (31 P NMR, l3 C NMR). 
  Reference    Z. Naturforsch. 43b, 915—917 (1988); eingegangen am 18. März 1988 
  Published    1988 
  Keywords    Benzyl-phosphines, Conformation, Crystal Structure 
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 TEI-XML for    default:Reihe_B/43/ZNB-1988-43b-0915_n.pdf 
 Identifier    ZNB-1988-43b-0915_n 
 Volume    43 
6Author    G.Erhard Müller, Joachim Lachm, Jürgen RiedebRequires cookie*
 Title    Molekülstrukturen von (o-Brombenzyl)diphenylphosphan und l,3-Bis(diphenylphosphinomethyl)benzol M olecular Structures of (o-Bromobenzyl)diphenylphosphine and l,3-Bis(diphenylphosphinomethyl)benzene  
  Reference    Z. Naturforsch. 47b, 823—828 (1992); eingegangen am 3. Februar 1992 
  Published    1992 
  Keywords    Benzylphosphines, Conformation, Crystal Structure 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0823.pdf 
 Identifier    ZNB-1992-47b-0823 
 Volume    47 
7Author    Christian Meyer3, Dietrich Mootza, Birgit Bäckb, Rolf MinkwitzbRequires cookie*
 Title    Bis(trifluormethyl)disulfan und -trisulfan: Molekülgeometrie im festen Zustand [1] Bis(trifluoromethyl)disulfane and Trisulfane: Molecular Geometry in the Solid State [1]  
 Abstract    The solid-state structures of the low-melting compounds bis(trifluoromethyl)disulfane (CF3SSCF3, triclinic, space group P I, Z = 2) and bis(trifluoromethyl)trisulfane (CF3SSSCF3, monoclinic, space group C2/c, Z = 4) have been determined on single crystals with M oK a radiation at -160°C. The trisulfane has trans conformation. The geometry of both molecules agrees well with results of electron diffraction on the gaseous state. A comparison is made also with the crystal structures of the related molecules CF3TeTeCF3 and CF3OOOCF3. 
  Reference    (Z. Naturforsch. 52b, 69—71 [1997]; eingegangen am 15. Juli 1996) 
  Published    1997 
  Keywords    Conformation, Crystal Structure, Sulfane 
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 TEI-XML for    default:Reihe_B/52/ZNB-1997-52b-0069.pdf 
 Identifier    ZNB-1997-52b-0069 
 Volume    52 
8Author    H.-D Liidemann, H. Pladi, E. W. Esthof, L. B. TownsendRequires cookie*
 Title    Conformations of 3-Deazaadenosine, 3-Deaza-8-azaadenosine, and Benzimidazole-1-ß-D-riboside in Solution: H RNM R-, Proton-Relaxation-Time-, and Nuclear-Overhauser- Effect Studies  
 Abstract    The solution conformations of 3-deazaadenosine, 3-deaza-8-azaadenosine, and benzimidazole-l-/5-D-riboside have been determined by nuclear magnetic resonance methods in aqueous and ammonia solutions. The two-state S N model of Altona and Sundaralingam is used to analyse the ribose moiety. In order to characterize the orientation of the base relative to the ribose, longitudinal proton relaxation time and nuclear Overhauser enhancement measurements have been carried out. It is shown that 3-deazaadenosine and benzimidazole-l-/?-D-riboside exist preferentially in the S-syn-g+/t (70%) and the N-anti-g+/t (30%) conformation families. In the case of 3-deaza-8-aza-adenosine, some destabilization of the g+ rotamer occurs. In this case, the pulsed methods seem to indicate a preference of the base for the anti range. 
  Reference    Z. Naturforsch. 33c, 305 (1978); received February 17/March 30 1978 
  Published    1978 
  Keywords    Nucleosideanalogs, Conformations, NMR, NOE 
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 TEI-XML for    default:Reihe_C/33/ZNC-1978-33c-0305.pdf 
 Identifier    ZNC-1978-33c-0305 
 Volume    33 
9Author    G. Klimke, I. Cuno, H.-D Lüdem, R. Mengel, M. J. RobinsRequires cookie*
 Title    Arabinose Conformations of 9-ß -D-Arabinofuranosyladenine (ARA-A) Analogues Modified at the 2',3' or 5' Positions  
 Abstract    The solution conformations o f 9-/?-D-arabinofuranosyladenine analogues modified at the 2',3' or 5' positions are derived from the HRNMR spectra and the longitudinal relaxation rates o f the protons. The compounds studied are: 9-/?-D-arabinofuranosyladenine and its 2/-amino-2'-deoxy, 2'-chloro-2'-deoxy, 2'-azido-2'-deoxy, 3'-amino-3'-deoxy, 3'-bromo-3'-deoxy, 3'-chloro-3'-deoxy, 3'-fluoro-3'-deoxy, 3'-azido-3'-deoxy, 2',3'-diamino-2/,3'-dideoxy, 2',5'-diamino-2',5'-di-deoxy and 2',5'-diazido-2',5'-dideoxy analogues. It is derived from the data that the conforma­ tional equilibria o f the furanoside rings can be described by the two state N <*> S model of Altona and Sundaralingam. The emphasis in this work is to study systematically the influence o f the different chemical modifications upon the conformational equilibria o f the nucleosides. For the arabinosides it is found that substitution o f the hydroxyl groups at C2' or C3' by other atoms or groups always stabilizes the N conformation of the arabinose ring. The only exception is fluorine, where S is stabilized. The preference for the N state is correlated with an increasing population o f the g + rotamer of the exocyclic 5'-CH2OD group. From the relaxation study o f 2'-chloro-2'-deoxy-arabinofuranosyladenine the position of the syn <=> anti equilibrium o f the base was estimated to be predominantly anti. Thus a preference for the anti-N-g+ conformation was derived for the arabinosides excluding an intramolecular hydrogen bond between the 2' and 5' hydroxyl groups that was found in the solid state. The stabilization o f the N conformer in the modified compounds can be qualitatively explained by steric effects. 
  Reference    Z. Naturforsch. 35c, 853 (1980); received June 25 1980 
  Published    1980 
  Keywords    Arabinofuranosyladenine Analogues, Conformation, NMR 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0853.pdf 
 Identifier    ZNC-1980-35c-0853 
 Volume    35 
10Author    G. Klimke, I. Cuno, H.-D Lüdemann, R. Mengel, M. J. RobinsRequires cookie*
 Title    Xylose Conformations of 9-/?-D-Xylofuranosyladenine Analogues Modified at the 2'3' or 5'-Positions and Lyxose Conformations of 9-^-D-Lyxofuranosyladenine  
 Abstract    Proton magnetic resonance studies o f 9-/?-D-xylofuranosyladenine (xyloA), its 2'-amino-2'-deoxy, 2'-azido-2'-deoxy, 2'-bromo-2'-deoxy, 3'-thio-3'-deoxy, 3'-amino-3'-deoxy, 3'-azido-3'-deoxy, 3'-chloro-3'-deoxy, 3'-fluoro-3'-deoxy, 3'-0-methyl, 3',5'-diazido-3',5'-dideoxy analogues and 9-/?-D-lyxofuranosyladenine (lyxoA) have been carried out to study the effect o f chemical modifications at the sugar moiety on the solution conformational equilibria in these classes of nucleosides. Analogously to previous studies the xylose pucker can be described in the two-state N <=> 5 model o f Altona and Sundaralingam. For the xylosides, however, a somewhat different N state (C3'-endo-C4'-exo) has to be used than for the ribosides and arabinosides (C2'-exo-C3'-endo). The results o f the conformational analysis are that xyloA exists almost exclusively as an N conformer. The effect o f the substitutions in the modified compounds is to destabilize the N state. This decrease in the mole fraction o f N is accompanied by an increase in the population of the g + rotamer o f the exocylic 5'-CH2OD group. Thus for the xylosides a correlation N-t/g~ or S-g +, respectively, can be derived. Proton relaxation rate measurements on 2'-azido-2'-deoxyxylo-furanosyladenine indicate that in the xylosides the standard syn or anti ranges do not represent stable positions for the adenine base, but that a glycosyl torsion angle (* ~ 160°, T ~ 80°) be­ tween syn and anti is preferred. LyxoA behaves similar to the xylosides and also favours the N state o f the sugar pucker. In a summarizing discussion the conformational equilibria o f the different modified pentosides -ribose, arabinose, xylose and lyxose -are compared. It is shown that generally intramolecular hydrogen bonding does not yield an important contribution to the stabilization o f conformational equilibria in solution. It is also not possible to derive a quantitative relationship between such parameters as Van-der-Waals' radii or electronegativity o f the substituents and the mole fractions of the different conformers. It can, however, be seen that in all cases, where the hydroxyl groups at C2' or C3' are substituted by a more voluminous atom or group, steric effects become dominant and allow a qualitative explanation o f the changes of the conformational equilibria. Only for the smallest and most electronegative substituents, like fluorine, other interactions (e. g. electrostatic) may become important. It is thus suggested that the purine(/7)nucleoside conforma­ tion is essentially determined by steric interactions between the different parts o f the molecule. 
  Reference    Z. Naturforsch. 35c, 865—877 (1980); received June 251980 
  Published    1980 
  Keywords    Adenosine Analogues, Conformation, NMR 
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 TEI-XML for    default:Reihe_C/35/ZNC-1980-35c-0865.pdf 
 Identifier    ZNC-1980-35c-0865 
 Volume    35 
11Author    V. Vill, J. ThiemRequires cookie*
 Title    Flüssigkristalle mit monosubstituierten alicyclischen und heteroalicyclischen Ringen Liquid Crystals Derived from Mono-Substituted Alicyclic and Heteroalicyclic Rings  
 Abstract    Twenty two liquid crystalline mono-substituted cyclopentanes and cyclohexanes including their oxygen analogues were prepard and studied. Smectic phases with clearing temperatures 5^80 °C were observed, and these do not differ considerably between the esters of the more flexible five-mem-bered ring derivatives and those of the conformationally more rigid six-membered rings. In case of the latter, decreasing clearing points ar observed with increasing ratios of the axial conformation (static conformational effect). Altogether rather low clearing points are observed, which may be interpreted by a dynamic conformational effect owing to which fast ring inversion causes the compounds to appear in a bulkier shape, and this results in a disadvantageous packing in the mesophase. 
  Reference    Z. Naturforsch. 45a, 1345—1348 (1990); eingegangen am 21. Oktober 1990 
  Published    1990 
  Keywords    Alicyclic rings, Liquid crystals, Conformation, Oxygen heterocycles 
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 TEI-XML for    default:Reihe_A/45/ZNA-1990-45a-1345.pdf 
 Identifier    ZNA-1990-45a-1345 
 Volume    45 
12Author    P. P. Nath, S. Sarkar, P.S R Krishna3, R. N. JoarderRequires cookie*
 Title    Molecular Conformation and Structural Correlations of Liquid D-terf-Butanol at Room Temperature by Neutron Diffraction  
 Abstract    An analysis o f neutron diffraction data o f liquid deuterated terr-butanol at room temperature to determine its molecular conformation is presented. Being a big molecule o f 15 sites, the analysis is tricky and needs careful consideration. The resulting molecular parameters are compared with those obtained from other experimental data analysis and model calculations. The information about the intermolecular structural correlations, hydrogen-bonded molecular association in partcular is also obtained from the diffraction data analysis. -PACS number: 61.25 
  Reference    Z. Naturforsch. 56a, 825—831 (2001); received August 13 2001 
  Published    2001 
  Keywords    Conformation, Structure, Correlation, D-terr-Butanol, Neutron Diffraction 
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 TEI-XML for    default:Reihe_A/56/ZNA-2001-56a-0825.pdf 
 Identifier    ZNA-2001-56a-0825 
 Volume    56 
13Author    Requires cookie*
 Title    Three-membered Rings. Molecular Structure and Conformation of Aryl Substituted Oxiranes by Dipole Moment Measurements  
 Abstract    and C a r l o B a t t i s t i n i , B r u n o M a c c h i a , a n d F r a n c o M a c c h i a The electric dipole moments of some styrene and trans-and cis-stilbene oxides have been measured, in benzene. From these data some bond angles have been calculated and it has been deduced that in the styrene derivatives the phenyl group is in rapid interconversion about the bond with the triatomic ring. 
  Reference    (Z. Naturforsch. 32b, 1467—1472 [1977]; received April 22 1977) 
  Published    1977 
  Keywords    Styrene Oxides, Stilbene Oxides, Structure, Conformation, Dipole Moments 
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 TEI-XML for    default:Reihe_B/32/ZNB-1977-32b-1467.pdf 
 Identifier    ZNB-1977-32b-1467 
 Volume    32 
14Author    Salvatore SorrisoRequires cookie*
 Title    Dielectric Measurements and Molecular Structure. Styrene Oxides and Phenylcyclopropanes  
 Abstract    The effects of electronic structure and conformation of the molecules YC6H4CHOCH2 1 1 (Y = o, m, and p-Cl) and Y'C6H4CHCCl2CH2 (Y' = o, and m-Cl) have been studied in benzene between 10.0 and 70.0 °C. In the oxirane systems the conjugation between the two rings is very small, if present at all; consequently, in the absence of steric and/or electrostatic hindrance internal rotation is observed. In the cyclopropane systems ex-amined these steric effects are sufficiently important to completely immobilise the molec-ular structure. 
  Reference    Z. Naturforsch. 34b, 1298—1302 (1979); received March 8/May 7 1979 
  Published    1979 
  Keywords    Styrene Oxides, Cyclopropanes, Conformation, Dipole Moments 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1298.pdf 
 Identifier    ZNB-1979-34b-1298 
 Volume    34 
15Author    Heinz Falk, Klaus ThirringRequires cookie*
 Title    Beiträge zur Chemie der Pyrrolpigmente, XXXIII [1] Darstellung, Struktur und Eigenschaften von isomeren N-Methyl-Bilatrienen-abc (N-Methyl-etiobiliverdine-IV-y) On the Chemistry of Pyrrole Pigments, XXXIII [1] Synthesis, Structure and Properties of Isomeric N-Methyl-bilatrienes-abc (N-Methyl-etiobiliverdines-IV-y)  
 Abstract    Methylation of etiobiliverdin-IV-y yields a ring-A N-methylated product the structure of which was proven by comparison with the corresponding monolactimether and the ring-B methylated product which was synthesized on an independent route. The configura-tion (Z,Z,Z) was deduced by iH-NMR experiments and a more or less helical conformation which is most twisted at the ring-A methine fragment was found. Photoisomerization exclusively takes place at this position giving the (E,Z,Z) diastereomer, a reaction which is discussed in terms of the correlation of light absorption, methine single bond twist and photochemical selectivity. 
  Reference    Z. Naturforsch. 34b, 1448—1453 (1979); eingegangen am 25. Mai 1979 
  Published    1979 
  Keywords    UY-VIS, iH-NMR, Photoisomerization, Configuration, Conformation 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1448.pdf 
 Identifier    ZNB-1979-34b-1448 
 Volume    34 
16Author    K. Barlos, Heinrich NöthRequires cookie*
 Title    Beiträge zur Chemie des Bors, CVIII [1] Synthese und Konformation yon N.N'-Bis(boryl)-N.N'-dimethylhydrazinen Contributions to the Chemistry of Boron, CVIII [1] Synthesis and Conformation of N,N , -Bis(boryl)-N,N'-dimethylhydrazines N,N'-Bis(methylboryl)-N,N'-dimethyl-hydrazine, N,N'-Bis(dichlor-boryl)-N,N  
  Reference    (Z. Naturforsch. 35b, 125—132 [1980]; eingegangen am 10. August 1979) 
  Published    1980 
  Keywords    -dimethyl-hydrazine, Conformation, NMR Spectra, PE Spectra 
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 TEI-XML for    default:Reihe_B/35/ZNB-1980-35b-0125.pdf 
 Identifier    ZNB-1980-35b-0125 
 Volume    35 
17Author    Harald Lehner, Corinna Krauss, Hugo ScheerRequires cookie*
 Title    Solvent Induced Circular Dichroism in Conformational Analysis: Bile Pigments  
 Abstract    The applicability of solvent induced circular dichroism (SICD) for the conformational analysis of bile pigments has been investigated. The S-(—)-ethyl lactate induced rotational strengths for octaethylbilindion (4) and its dihydroderivative 5 are remarkably high. Related compounds, e.g. the isomeric purpurines 1 and 2 and formyltripyrrinon 3 exhibit an optical activity which is smaller by more than one order of magnitude. 1-3 are essen-tially free from steric strain so that a flat arrangement of the chromophore is most likely. On the other hand the closed conformations of 4 and 5 experience considerable steric repulsion of their terminal rings, so that a helical topology is energetically favoured. This distinction is reflected in the magnitude of the SICD observed and demonstrates its applicability for the conformational analysis of bile pigments. 
  Reference    Z. Naturforsch. 36b, 735—738 (1981); received November 21 1980 
  Published    1981 
  Keywords    Solvent Induced Circular Dichroism, Conformation, Enantiomerization, Purpurines, Bilatrienes 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0735.pdf 
 Identifier    ZNB-1981-36b-0735 
 Volume    36 
18Author    Rainer Mattes, Franz WaldmannRequires cookie*
 Title    Molekülstruktureii, Schwingungsspektren und Konformation der Thiooxalsäurederivate CH3S-CO-CONH2, CH3S-CS-CONH2, C2H50-C0-CSNH2 und K[OSC-CONH2] Molecular Structure, Vibrational Spectra and Conformation of the Thiooxalic Acid Derivatives CH3S-CO-CONH2, CH3S-CS-CONH2, C2H50-C0-CSNH2 and K[OSC-CONH2]  
 Abstract    The crystal structures ofCH3S-CO-CONH2 (1), CH3S-CS-CONH2 (2), C2H50-C0-CSNH2 (3) and K[OSC-CONH2] (4) have been determined by single crystal X-ray diffraction. The molecules 1, 2 and 3 are nearly planar and form centrosymmetric dimers by N H • • • O or N-H--S hydrogen bonds with the amidic oxygen or sulfur atom as acceptor atoms. The anion of 4 is not quite planar. The torsional angle around the C-C bond is 18.4°. The con-formations of the title compounds are E, Z' (1 and 2), Z, Z' (3) and Z (4). According to the vibrational spectra, which are discussed briefly, 1 and 3 retain their conformation also in solution. 
  Reference    Z. Naturforsch. 38b, 335—340 (1983); eingegangen am 5. November 1982 
  Published    1983 
  Keywords    Molecular Structure, Conformation, Vibrational Spectra, Thiooxalic Acid Derivatives 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0335.pdf 
 Identifier    ZNB-1983-38b-0335 
 Volume    38 
19Author    Ludwig Roß, Martin DrägerRequires cookie*
 Title    Phases of Decaphenylcyclopentagermane (Ph2Ge)s [1]  
 Abstract    (Pb^Ges) can be obtained from solutions in five crystalline phases, two pure and three including solvent of crystallization. This is lost at 70 °C. At 190 °C all phases transform into a plastic crystalline phase. For this tetragonal phase a gear wheel model for librations of the molecules is developed. The crystal structure of triclinic (Ph2Ge)s has been determined and refined to R = 0.050. The molecule has a flexible conformation in accordance with a better solubility than exhibited by the homologous rings (Ph2Ge)4 and (Ph2Ge)6 containing rigid normal conformations. The arrangement of phenyl groups is either parallel or perpendicular for both cases intra-and intermolecular. The compound (Ph2Ge)6 attains a plastic crystalline state at 346 °C. 
  Reference    Z. Naturforsch. 38b, 665—673 (1983); eingegangen am 28. Januar 1983 
  Published    1983 
  Keywords    Germanium, Homocycle, Conformation, Plastic Crystalline State 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0665.pdf 
 Identifier    ZNB-1983-38b-0665 
 Volume    38 
20Author    Anders Ljungqvist, Karl FolkersRequires cookie*
 Title    Study of Hydrogenolytic Cleavage of Peptide-Resin Benzyl Ester Bonds for Synthesis of Protected Fragments of the Human Leukocyte Interferon  
 Abstract    Three Boc-protected fragments of the human leukocyte interferon, LeIFA, have been synthesized: I, BOC LeIFA (99-105) (BOC-Val-Ile-Gln-Gly-Val-Gly-Val); II, BOC LeIFA (116-119) (BOC-Ile-Leu-Ala-Val); III, BOC LeIFA (123-126) (BOC-Phe-Gln-Arg(Tos)-Ile). The presence of the Boc-group was desired so that these peptides could serve as intermediates in fragment condensation toward larger segments of interferon. To achieve these intermediates, a study was desirable on three methods of cleavage of the benzyl ester-polymer bonds. It was found that hydrogenolysis with hydrogen and palla-dium generated in situ was distinctly superior to transfer hydrogenation with ammonium formate or cyclohexene. An effective swelling of the peptide-resin to allow penetration of palladium acetate into the matrix and mobility of the peptide chains on the resin to expose the benzyl ester bond to hydrogenolysis appear to be essential conditions for the best cleavage. 
  Reference    Z. Naturforsch. 38b, 1022—1024 (1983); received May 2 1983 
  Published    1983 
  Keywords    Interferon, Peptide Synthesis, Hydrogenation, Palladium Black, Conformation 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-1022.pdf 
 Identifier    ZNB-1983-38b-1022 
 Volume    38