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'3' in keywords Facet   Publication Year 1996  [X]
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1996[X]
1Author    Stephan Friederichs, Jens Kudnig, Günter KlarRequires cookie*
 Title    Elementorganische Verbindungen mit o-Phenylenresten, XXVIII [1] Charge-transfer  
 Abstract    Komplexe von 2,3,7,8-Tetraalkoxy-chalkogenanthrenen mit 7,7,8,8-Tetracyan-2,3?5,6-tetrafluor-chinodimethan Organometalloidal Compounds with o-Phenylene Substituents, Part XXVIII [1] Charge-Transfer Complexes of 2,3,7,8-Tetraalkoxy-chalcogenanthrenes wjth 7.7.8.8-Tetracyano-2,3,5,6-tetrafluoro-quinodimethane -selenanthrene, as well as -tetraethoxythianthrene gi­ ve isostructural 1:1 charge-transfer complexes with 7,7,8,8-tetracyano-2,3,5,6-tetrafluoro-quinodimethane. In the columnar crystal structures there are alternating donor and acceptor molecules. The chalcogenanthrene molecules which are folded at their E -E axes in the pure state, are planar in the complexes indicating a charge-transfer according to [donor]+ [acceptor]-. Consecutive molecules of the stacks are arranged in such a way that an optimum overlap of the HOMO of the donor and the LUMO of the acceptor, both of which are of 7T-type character according to MNDO calculations, is secured. 
  Reference    Z. Naturforsch. 51b, 1295—1300 (1996); eingegangen am 1. April 
  Published    1996 
  Keywords    Tetracyano-2, 3, 5, 6-tetrafiuoro-quinodi-methane, 1:1 Charge-Transfer Complexes, Columnar Structures, MNDO Calculations 2, 3, 7, 8-Tetramethoxythianthrene and 
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 TEI-XML for    default:Reihe_B/51/ZNB-1996-51b-1295.pdf 
 Identifier    ZNB-1996-51b-1295 
 Volume    51 
2Author    VasilyRequires cookie*
 Title    Chemistry of the l,3>5-Triaza-2-phosphorin-4,6-diones, Part XII*. Synthesis and Characterization of 2-PhenyI-2-(/?-tolylthio)-l,3?5- trimethyI-l,3,5-triaza-4,6-dione-2-phosphorinonium Salts  
 Abstract    A . P in ch u k , Io n N e d a , C h ristian M üller, H o lg e r T h ö n n e ss e n , P e te r G. Jones, R e in h a rd S chm utzler The reaction of l,5-bis(trimethylsilyl)-l,3.5-trimethylbiuret (1) with/M olylsulfenyl chloride (2) furnished l-(/?-tolylthio)-5-trimethylsilyl-l,3,5-trimethylbiuret (3). In the reaction of 3 with phenyldichlorophosphine, 2-phenyl-2-(/?-tolylthio)-l,3,5-trimethyl-l,3,5-triaza-4,6-dione-2-phosphorinonium chloride (4) was formed. The same product was obtained from the reac­ tion of 2-phenyl-l,3,5-trimethyl-l,3,5-triaza-2/.3-phosphorin-4,6-dione (6) with p-tolylsulfenyl chloride (2). Compound 4 was isolated and characterized in the form of the hexachloroanti-m onate (4a). The spirophosphorane 2-phenyl-l,3,5-trimethyl-l,3,5-triaza-7,10-dioxa-8,9-perchlorobenzo-2As-phosphaspiro-[4.5]decan-4,6-dione (7) was prepared by the reaction of 4 with tetrachloroorthobenzoquinone. The new products were characterized by 'H -and 13C NMR spectroscopy, elemental analysis, 31P NMR spectroscopy in the case of 4a. 6 and 7, and mass spectrometry (4a). Single-crystal X-ray structural analyses of compounds 4a and 7 were conducted. The phosphorus atom of 4a has the expected tetrahedral geometry, with a rather short P-S bond of 204.9(2) pm. In 7 the geometry at phosphorus is almost ideal trigonal bipyramidal. Weak hydrogen bonds are formed from a C (:0) group to deuterochloroform of solvation. 
  Reference    Z. Naturforsch. 51b, 1494—1500 (1996); received February 13 1996 
  Published    1996 
  Keywords    1, 3, 5-Trimethyl-Substituted 1, 3, 5-Triaza-4, 6-dione-2-phosphorinonium Derivatives, Intram olecular Rearrangem ent, NMR Spectra, X-Ray 
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 TEI-XML for    default:Reihe_B/51/ZNB-1996-51b-1494.pdf 
 Identifier    ZNB-1996-51b-1494 
 Volume    51 
3Author    D. Ietrich, Bäum Er, HansG. Eorg RuppelRequires cookie*
 Title    Phenolic Constituents of Galactites tomentosa (Asteraceae)  
 Abstract    The A steracea Galactites tomentosa. known as a plant causing allergic contact reactions, was investigated for new constituents in leaves and stems. Chlorogenic acid and 3,5-dicaf-feoylquinic acid could be detected by H P LC in tissues and trichome preparations as well. 
  Reference    Z. Naturforsch. 51c, 623 (1996); received May 31/June 20 1996 
  Published    1996 
  Keywords    Allergie Contact Reactions, Galactites tomentosa, Chlorogenic Acid, 3, 5-Dicaffeoylquinic Acid 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0623.pdf 
 Identifier    ZNC-1996-51c-0623 
 Volume    51 
4Author    H. Möhrle, U. Von Der Lieck-WaldheimRequires cookie*
 Title    Vinamidinium-Salze als Nucleophile Vinamidinium Salts as N ucleophiles  
 Abstract    1,4-diazepinium salts could not be aminomethylated with conventional methods, but the hydrochlorides produced with methyleniminium salts the C-Mannich-compounds. The reactivity of the substrate was mainly controlled by electronic effects of the substituents. Aminomethylation of 1,5-diazapentadienium salts occurred only if the conformations caused no steric hindrance of the ß-C-atom. Methyl substituted 2,3-dihydro-1,4-diazepinium salts reacted with 1,3,5 triazine to pyrimidine anellated derivatives. 
  Reference    Z. Naturforsch. 51b, 421—430 (1996); eingegangen am 4. Juli 1995 
  Published    1996 
  Keywords    Mannich Reaction, Iminium Salts, 1, 3, 5 Triazine, Push-Pull-Systems 2, 3-Dihydro- 
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 TEI-XML for    default:Reihe_B/51/ZNB-1996-51b-0421.pdf 
 Identifier    ZNB-1996-51b-0421 
 Volume    51 
5Author    Ferdinand BelajRequires cookie*
 Title    Struktur von C2C16N4P2, dem R eaktionsprodukt von D icyandiam id mit PC15 Structure of C 2C16N4P2, the Reaction Product of Dicyandiamide with PC15  
 Abstract    The reaction product of dicyanodiamide with PC15 (1:2) is 2,2,4-trichloro-2,2-dihydro-6-trichlorophosphazeno-1.3,5,2A5-triazaphosphorine and not 2.4,6-trichloro-2,2-dihydro-2-trichlorophosphazeno-l,3,5,2A5-triazaphosphorine as reported in the literature. This is con­ firmed by an X-ray structure determination at 90K: Space group P 2,/c, a = 17.258(5), b = 9.664(3), c = 15.070(4) Ä, ß = 114.05(2)°, Z = 8, R = 3.99%. Both molecules of the asymmetric unit show about the same conformation with approximate C s-m -symmetry as was also obtai­ ned by semi-empirical MNDO calculations. The thermal motion analysis establishes that the molecules cannot be described as 'rigid bodies', and that the easy deformability of the exocyclic C-N-P angles allows the 'rigid' NPC13 tetrahedra to perform almost isotropic librations. 
  Reference    Z. Naturforsch. 51b, 1428—1432 (1996); eingegangen am 20. Februar 1996 
  Published    1996 
  Keywords    2, 24-Trichloro-2, 2-dihydro-6-trichlorophosphazeno-l, 3, 5, 2A5-triazaphosphorine Phosphaze­ ne, Crystal Structure, Thermal Motion Analysis 
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 TEI-XML for    default:Reihe_B/51/ZNB-1996-51b-1428.pdf 
 Identifier    ZNB-1996-51b-1428 
 Volume    51 
6Author    Hans Rausch, GeorgG. GrossRequires cookie*
 Title    Preparation of [14C]-LabeIled l,2,3,4,6-Penta-0-Gal!oyl-/?-D-Glucose and Related Gallotannins  
 Abstract    [U -14C]-Labelled 1,2,3,4,6-penta-O-galloyl-ß-D-glucose was prepared by photoassimilation of 14C 0 2 with leaves from staghorn sumac (Rhus typhina) in the presence of the herbicide glyphosate. Extracts of the plant material were partitioned against ethyl acetate and chro­ matographed on Sephadex LH-20, yielding a series o f crude tri-to decagalloylglucoses. The pentagalloylglucose fraction among these was further purified by HPLC to >99% purity and a specific radioactivity of 130 kBq (3.5 fiCi) per fimol. The ratio of the radioactivities in the glucose and galloyl moieties, respectively, suggested a uniform labelling pattern of the product. 
  Reference    Z. Naturforsch. 51c, 473 (1996); received February 8/March 8 1996 
  Published    1996 
  Keywords    [I4C]l, 2, 3, 4, 6-Penta-0-galloyl-ß-D-glucopyranose, Gallotannins, Photosynthesis, Rhus typhina, Staghorn Sumac 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0473.pdf 
 Identifier    ZNC-1996-51c-0473 
 Volume    51 
7Author    Martin Semara, HeidrunA. Nke3, Wolf-Rüdiger Arendholzb, Robert Veiten0, Wolfgang Steglich0Requires cookie*
 Title    Lachnellins A, B, C, D, and Naphthalene-l,3,8-triol, Biologically Active Compounds from a Lachnellula Species (Ascomycetes)  
 Abstract    In the course of our search for new biologically active metabolites, lachnellin A (1), a metabolite with high cytotoxic and antimicrobial activities, the structurally related lachnellins B. C and D (3, 4, 7), and naphthalene-l,3,8-triol (8), an inhibitor of malate synthase (EC 4.1.3.2), were isolated from submerged cultures o f the ascomycete Lachnellula sp. A 3 2 -8 9 . The antimicrobial, cytotoxic and phytotoxic activities of lachnellin A depended on its reactiv­ ity and could be abolished by the addition of cysteine. The enzyme inhibiting activity of (8) was due to reactive intermediates during melanization and was no longer observed in the presence of serum albumin. In addition, rac-scytalone (9), (+)-fra/7s-3,4-dihydro-3,4,8-trihy-droxy-l(2//)-naphtha!enone (10). 2,5-dihydroxytoluene (11), and (/?)-(-)-5-methylmellein (12) were obtained from the same source and biologically characterized. 
  Reference    Z. Naturforsch. 51c, 500 (1996); received March 1/April 29 1996 
  Published    1996 
  Keywords    Lachnellin A, B, C D Glyoxylate Cycle, N aphthalene-1, 3, 8-triol, Malate Synthase, Melanization, Lachnellula sp 
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 TEI-XML for    default:Reihe_C/51/ZNC-1996-51c-0500.pdf 
 Identifier    ZNC-1996-51c-0500 
 Volume    51