@article{TackeLangeBentlageetal.1983,
  author    = {Tacke, Reinhold and Lange, Hartwig and Bentlage, Anke and Sheldrick, William S. and Ernst, Ludger},
  title     = {2.2.5.5-Tetraorganyl-1.4-dioxa-2.5-disilacyclohexane/2,2,5,5-Tetraorganyl-1,4-dioxa-2,5-disilacyclohexanes},
  series = {Zeitschrift f{\"u}r Naturforschung B},
  volume    = {38},
  journal   = {Zeitschrift f{\"u}r Naturforschung B},
  number    = {2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128423},
  pages     = {190-193},
  year      = {1983},
  abstract  = {The 2,2,5,5-tetraorganyl-1,4-dioxa-2,5-disilacyclohexanes 2a-2c were prepared by condensation of the corresponding (hydroxymethyl)diorganylsilanes 1 a-1 c. The constitution of the heterocycles was confirmed by elemental analyses, cryoscopic measurements, mass spectrometry, and NMR-spectroscopic \((^1H, ^{13}C)\) investigations. The molecular structure of 2 b was determined by X-ray diffraction analysis.},
  language  = {de}
}
@article{TackeLangeSheldricketal.1983,
  author    = {Tacke, Reinhold and Lange, Hartwig and Sheldrick, William S. and Lambrecht, G{\"u}nter and Moser, Ulrich and Mutschler, Ernst},
  title     = {Sila-Pharmaka, 31. Mitt. [1] Synthese, Struktur und pharmakologische Eigenschaften von Diphenyl(2-piperidinoethoxymethyl)silanol und seinem Kohlenstoff-Analogon},
  series = {Zeitschrift f{\"u}r Naturforschung B},
  volume    = {38},
  journal   = {Zeitschrift f{\"u}r Naturforschung B},
  number    = {6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128410},
  pages     = {738-746},
  year      = {1983},
  abstract  = {In the course of systematic investigations on sila-substituted parasympatholytics the diphenyl(2-aminoethoxymethyl)silanols 3b and 4b (and its carbon analogue 4a) were synthesized and characterized by their physical and chemical properties. In the solid state 4a and 4b form strong O-H---N hydrogen bonds, which are intramolecular (4a) and intermolecular (4b), respectively. 4a and 4b were found to be weak antimuscarinic agents (4b >4a) and strong papaverine-like spasmolytics (4a ≈4b).},
  language  = {de}
}
@article{TackeLinohAttarBashietal.1982,
  author    = {Tacke, Reinhold and Linoh, Haryanto and Attar-Bashi, Moayad T. and Sheldrick, William S. and Ernst, Ludger and Niedner, Roland and Frohnecke, Joachim},
  title     = {Sila-Pharmaka, 26. Mitt. [1] Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, III},
  series = {Zeitschrift f{\"u}r Naturforschung B},
  volume    = {37},
  journal   = {Zeitschrift f{\"u}r Naturforschung B},
  number    = {11},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128402},
  pages     = {1461-1471},
  year      = {1982},
  abstract  = {The potentially curare-like silicon compounds 8a- 8f were synthesized and investigated with respect to their structure-activity relationships. The conformations of the compounds in the solid state and in solution were studied by X-ray diffraction analysis (8a- 8e) and IR 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 {\AA} model" for neuromuscular blocking agents.},
  language  = {de}
}
@article{JaiswalLambrechtMutschleretal.1991,
  author    = {Jaiswal, Neelam and Lambrecht, G{\"u}nter and Mutschler, Ernst and Tacke, Reinhold and Malik, Kafait U.},
  title     = {Pharmacological characterization of the vascular muscarinic receptors mediating relaxation and contraction in rabbit aorta},
  series = {Journal of Pharmacology and Experimental Therapeutics},
  volume    = {258},
  journal   = {Journal of Pharmacology and Experimental Therapeutics},
  number    = {3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128358},
  pages     = {842-850},
  year      = {1991},
  abstract  = {Studies were performed in the rabbit aortic rings, precontracted with norepinephrine, to determine the subtype(s) of muscarinic receptors involved in endothelium-dependent relaxation and contraction in the absence of endothelium elicited by cholinergic stimuli. Acetylcholine (ACh) and arecaidine propargyl ester (APE), a M2 and M3 agonist, produced a dose-dependent relaxation and contraction in endothelium-intact and endothelium-denuded rabbit aortic rings, respectively. Both of these responses were blocked by the muscarinic receptor antagonist atropine. M1 selective agonist McN-A-343 [4-[N-(3-chlorophenyl)carbamoyloxy]-2-butinyltrimethylammonium+ ++ chloride] did not produce any effect on the tone of precontracted aortic rings. ACh- and APE-induced relaxation in aortic rings with intact endothelium was selectively blocked by M3 receptor antagonists hexahydrosila-difenidol and p-fluoro-hexahydro-sila-difenidol (pA2 of 7.84 and 7.18) but not by M1 antagonist pirenzepine or M2 receptor antagonists AF-DX 116 [11-(2-[(diethylamino)methyl]- 1-piperidinyl]acetyl)-5, 11-dihydro-6H-pyrido-[2,3-b][1,4]-benzo-diazepin-6-one] and methoctramine. ACh- and APE-induced contraction was inhibited by M2 receptor antagonists AF-DX 116 and methoctramine (pA2 of 7.11 and 6.71) but not by pirenzepine, hexahydro-sila-difenidol or p-fluoro-hexahydro-sila-difenidol. ACh- and APE-induced relaxation or contraction were not altered by nicotinic receptor antagonist hexamethonium or cyclooxygenase inhibitor indomethacin. These data suggest that relaxation elicited by cholinergic stimulin in endothelium-intact aortic rings is mediated via release of endothelium-derived relaxing factor consequent to activation of M3 receptors located on endothelial cells, whereas the contraction in aortic rings denuded of their endothelium is mediated via stimulation of M2 receptors located on smooth muscle cells.},
  language  = {en}
}
@article{TackeLinohStumpfetal.1983,
  author    = {Tacke, Reinhold and Linoh, Haryanto and Stumpf, Burghard and Abraham, Wolf-Rainer and Kieslich, Klaus and Ernst, Ludger},
  title     = {Mikrobiologische Umwandlung von Silicium-Verbindungen: Enantioselektive Reduktion von Acetessigs{\"a}ure-(trimethylsilylalkyl)estern und deren Carba-Analoga},
  series = {Zeitschrift f{\"u}r Naturforschung B},
  volume    = {38},
  journal   = {Zeitschrift f{\"u}r Naturforschung B},
  number    = {5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128304},
  pages     = {616-620},
  year      = {1983},
  abstract  = {The trimethylsilylalkyl acetoacetates 1 b and 2 b as well as their carba analogues 1 a and 2 a have been reduced microbiologically by Kloeckera corticis (ATCC 20109), leading to the corresponding ( + )-3(S)-hydroxybutanoates 3b, 4b, 3a, and 4a. The enantiomeric purity was found to be 80\% (3a, 3b, 4b) and 65\% (4a), respectively. The reduction of lb and 2b is - to our knowledge - the first example for a controlled microbiological transformation of organosilicon substrates.},
  language  = {de}
}
@article{TackeLinkBentlageFeltenetal.1985,
  author    = {Tacke, Reinhold and Link, Matthias and Bentlage-Felten, Anke and Zilch, Harald},
  title     = {Zum thermischen Verhalten einiger Kohlens{\"a}ure[(methylphenylsilyl)methyl]ester-Derivate},
  series = {Zeitschrift f{\"u}r Naturforschung B},
  volume    = {40},
  journal   = {Zeitschrift f{\"u}r Naturforschung B},
  number    = {7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128293},
  pages     = {942-947},
  year      = {1985},
  abstract  = {The synthesis and the thermal behaviour of the (methylphenylsilyl)methyl carbonates \(CH_3(C_6H_5)Si(H)CH_2OC(O)X (6: X = OCH_3; 7: X = Cl; 8: X = N(CH_3)_2)\) is described. 8 rearranges in toluene solution at 100 °C quantitatively to give the carbam oyloxysilane \(C_6H_5(CH_3)_2SiOC(O)N(CH_3)_2\) (11), whereas neat 6 and 7 at 135 °C undergo quantitative formation of \(C_6H_5(CH_3)_2SiOCH_3\) (12) and \(C_6H_5(CH_3)_2SiCl\) (13), respectively. The formation of 12 and 13 is explained by a rearrangement reaction (by analogy to the rearrangement of 8), follow ed by a decarboxylation. The thermally induced transformations 6 →12, 7 →13, and 8 →11 were found to be first-order reactions with half-lifes of ~2.6 h (135 °C, neat), ~4.5 h (135 °C, neat), and ~3.7 h (100 °C, in toluene), respectively.},
  language  = {de}
}
@article{TackeNiederer1978,
  author    = {Tacke, Reinhold and Niederer, Reinhold},
  title     = {Sila-Pharmaka, 9. Mitt. [1] Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, I},
  series = {Zeitschrift f{\"u}r Naturforschung B},
  volume    = {33},
  journal   = {Zeitschrift f{\"u}r Naturforschung B},
  number    = {4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128277},
  pages     = {412-416},
  year      = {1978},
  abstract  = {Organosilicon compounds 8, 9 and 10 with potential curare-like action and their precursors 0, 6 and 7 were synthesized for the first time. 0-10 were characterized by their physical and chemical properties, and their structures were confirmed by analyses, IH NMR and mass spectroscopy (only for 0-7). The pharmacological and toxicological data of 8, 9 and 10 are reported.},
  language  = {de}
}
@article{SaadTacke1977,
  author    = {Saad, S. M. and Tacke, Reinhold},
  title     = {Zur Darstellung von 1,1,3,3-Tetramethyl-1,3-disila-2,4,7-trioxa-cycloheptan (1) und 1,1,3,3-Tetramethyl-1,3-disila-2,4,8-trioxa-cyclooctan (2)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86958},
  year      = {1977},
  abstract  = {No abstract available.},
  subject      = {Anorganische Analyse},
  language  = {de}
}
@article{TackeBentlageFeltenLinohetal.1986,
  author    = {Tacke, Reinhold and Bentlage-Felten, Anke and Linoh, Haryanto and Magda, Stephen},
  title     = {Sila-Analoga des Triparanols und Ethamoxytriphetols: Synthese sowie pharmakologische und toxikologische Eigenschaften},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86940},
  year      = {1986},
  abstract  = {No abstract available.},
  language  = {de}
}
@article{TackeLinkJoppienetal.1986,
  author    = {Tacke, Reinhold and Link, Matthias and Joppien, Hartmut and Ernst, Ludger},
  title     = {Sila-Substitution des Akarizids Fenbutatinoxid und einiger seiner Derivate: Synthese und Eigenschaften von Hexakis[(dimethylphenylsilyl)methyl]distannoxan und Tris[(dimethylphenylsilyl)methyl](1,2,4-triazol-1-yl)stannan},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86937},
  year      = {1986},
  abstract  = {No abstract available.},
  subject      = {Chemische Synthese},
  language  = {de}
}
@article{TackeWiesenberger1991,
  author    = {Tacke, Reinhold and Wiesenberger, Frank},
  title     = {(Acetoxymethyl)methylphenylgerman: Synthese, thermisches Verhalten und olfaktorische Eigenschaften},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86927},
  year      = {1991},
  abstract  = {No abstract available.},
  subject      = {Chemische Synthese},
  language  = {de}
}
@article{TackeWiesenbergerLopezMrasetal.1992,
  author    = {Tacke, Reinhold and Wiesenberger, Frank and Lopez-Mras, Angel and Sperlich, J{\"o}rg and Mattern, G{\"u}nter},
  title     = {Neuartige zwitterionische λ5-Spirosilicate: Synthese und Kristallstruktur von Bis[1,2-benzoldiolato(2-)][2-(dimethylammonio)phenyl]silicat sowie Synthese von Bis[2,3-naphthalindiolato(2-)][2-(dimethylammonio)phenyl]silicat-Hemiacetonitril-Solvat},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86916},
  year      = {1992},
  abstract  = {No abstract available.},
  subject      = {Silicate},
  language  = {de}
}
@article{TackeKropfgansTafeletal.1994,
  author    = {Tacke, Reinhold and Kropfgans, Martin and Tafel, Andrea and Wiesenberger, Frank and Sheldrick, William S. and Mutschler, Ernst and Egerer, Hansj{\"o}rg and Rettenmayr, Nikola and Gross, Jan and Waelbroeck, Magali and Lambrecht, G{\"u}nter},
  title     = {(Hydroxymethyl)diphenyl(piperidinoalkyl)silane des Typs (HOCH2)(C6H5)2Si(CH2)nNC5H10 (n = 2,3) und deren Methoiodide: Synthese, Struktur und antimuscarinische Eigenschaften},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86904},
  year      = {1994},
  abstract  = {No abstract available.},
  language  = {de}
}
@article{TackeHallerZeiler1979,
  author    = {Tacke, Reinhold and Haller, Ingo and Zeiler, Hans-Joachim},
  title     = {Sila-Analoga der Antiseptica Octafoniumchlorid und p-tert-Butylphenol},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86893},
  year      = {1979},
  abstract  = {No abstract available.},
  subject      = {Silaanaloga},
  language  = {de}
}
@article{TackeSperlichStrohmannetal.1992,
  author    = {Tacke, Reinhold and Sperlich, J{\"o}rg and Strohmann, Carsten and Frank, Brigitta and Mattern, G{\"u}nter},
  title     = {Bis[3,4,5,6-tetrabrom-1,2-benzoldiolato(2-)]-(pyrrolidiniomethyl)silicat-Acetonitril-Solvat [(C6Br4O2)2SiCH2(H)NC4H8 · CH3CN]: Synthese sowie Kristall- und Molek{\"u}lstruktur eines zwitterionischen [lambda]5-Spirosilicats},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-86884},
  year      = {1992},
  abstract  = {Single crystal X-ray studies on bis[3,4,5,6-tetrabromo-1 ,2-benzenediolato(2- )](pyrrolidiniomethyl)silicate acetonitrile solvate [(C6Br40 2hSiCH2(H)NC4H8 · CH3CN; monoclinic, P2t/c, a = 808.5(4), b = 1533.0(8), c = 2212.6(1) pm, ß = 97.67(2)0 , Z = 4] revealed a zwitterionic structure with a pentacoordinate, formally negatively charged silicon atom and a positively charged ammonium moiety. The silicon atom is surrounded by four oxygen atoms and one carbon atom in a trigonalbipyramidal fashion, with the carbon atom in an equatorial position. The structure is displaced by 7.0\% from the trigonal bipyramid towards the square pyramid. The zwitterion and the CH3CN molecule form intermolecular N-H · · · N hydrogen bonds.},
  subject      = {Kristallstruktur},
  language  = {de}
}
@article{SperlichBechtMuehleisenetal.1993,
  author    = {Sperlich, J{\"o}rg and Becht, Joachim and M{\"u}hleisen, Mathias and Wagner, Stephan A. and Mattern, G{\"u}nter and Tacke, Reinhold},
  title     = {Zwitterionische Bis[vic-arendiolato(2-)][(morpholinio)alkyl]silicate: Synthese sowie strukturelle Charakterisierung in L{\"o}sung und im Kristall},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-73153},
  year      = {1993},
  abstract  = {No abstract available.},
  subject      = {Silicate},
  language  = {de}
}
@article{TackeBentlagemTowartetal.1980,
  author    = {Tacke, Reinhold and Bentlagem, A. and Towart, R. and Meyer, H. and Bossert, F. and Vater, W. and Stoepe, K.},
  title     = {Sila-Analoga von Nifedipin-{\"a}hnlichen 4-Aryl-2.6-dimethyl-1.4-dihydropyridin-3.5-dicarbons{\"a}ure-dialkylestern, I},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-82430},
  year      = {1980},
  abstract  = {no abstract available},
  subject      = {Chemie},
  language  = {de}
}
@article{TackeSaad1977,
  author    = {Tacke, Reinhold and Saad, S. M.},
  title     = {Silylation of cellulose},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-78368},
  year      = {1977},
  abstract  = {Ethane-l:2-diol and propane-l:3-diol reaet with 1: 1:3:3-tetramethyl-l:3-dichlorodisiloxane forming the corresponding rings. However, no ring compounds could be traced tbrough the reaction between butane-l :4-diol, glycerol and the dichlorodisiloxane respectively, where only polymeric compounds are formed. The silylation products of the di- and trihydroxy alcohols, as model compounds, has confirmed that the ring formation during silylation of cellulose with dichlorodisiloxane is uncertain.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeBentlageTowartetal.1983,
  author    = {Tacke, Reinhold and Bentlage, Anke and Towart, Robertson and M{\"o}ller, Eike},
  title     = {Sila-pharmaca, XXV. Sila-analogues of nifedipine-like dialkyl 2,6-dimethyl-4-aryl-1,4 dihydropyridine-3,5-dicarboxylates, III},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-78357},
  year      = {1983},
  abstract  = {IS neue C/Si-Analogenpaare (C-Verbindungen und sila- bzw. disila-substituierte Derivate), die sich strukturell vom Nifedipin ableiten, wurden synthetisiert. Diese und einige weitere C/Si-Paare wurden hinsichtlich ihrer physikochemischen und pharmakologischen Eigenschaften vergleichend untersucht. Mittels reversed-phase-D{\"u}nnschichtchromatographie wurde gezeigt, daß die Sila- bzw. Disila-Analoga lipophiler sind als die entsprechenden C-Verbindungen. Bez{\"u}glich der spasmolytischen in vitra-Aktivit{\"a}ten zeigen die Si-Verbindungen in erster N{\"a}herung {\"a}hnliche Struktur-Wirkungs-Beziehungen wie ihre Carba-Analoga. Dagegen konnten hinsichtlich der ill vlva-Effekte (cardiovascul{\"a}re und antihypertensive Aktivit{\"a}t) in einigen F{\"a}llen große Unterschiede nachgewiesen werden.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeWuttkeHenke1992,
  author    = {Tacke, Reinhold and Wuttke, F. and Henke, H.},
  title     = {Zur Stereochemie der mikrobiellen Reduktion von rac-Acetyl( t-butyl)methylphenylsilan mit Trigonopsis variabilis (DSM 70714) und Corynebacterium dioxydans (ATCC 21766): Aufkl{\"a}rung der absoluten Konfiguration der Biotransformationsprodukte (SiR,CR)- und ( SiS ,CR)-t-Butyl( 1-hydroxyethyl)methylphenylsilan},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64176},
  year      = {1992},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeMuehleisen1994,
  author    = {Tacke, Reinhold and M{\"u}hleisen, M.},
  title     = {Bis[benzilato(2-)-O\(^1\),O\(^2\)][2-(dimethylammonio)ethoxy]silicate: synthesis and structural characterization of a zwitterionic \(\lambda^5\)Si-silicate with a SiO\(_5\) framework},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64400},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{MuehleisenTacke1994,
  author    = {M{\"u}hleisen, M. and Tacke, Reinhold},
  title     = {meso-[1,4-Piperaziniumdiylbis(methylene)]bis{bis[2-methyllactato(2-)-O1,O2]silicate} octahydrate: synthesis and crystal structure analysis of a zwitterionic dispirocyclic \(\lambda^5\)Si,\(\lambda^5\)Si'-disilicate},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64396},
  year      = {1994},
  abstract  = {The zwitterionic dispirocyclic \(\lambda^5\)Si,\(\lambda^5\)Si'-disilicate meso-[1 ,4-piperaziniumdiylbis( methylene)]bis{ bis[ 2-methyllactato(2-)-O\(^1\),O\(^2\)]silicate} octahydrate (6-8H\(_2\)O) was synthesized by reaction of 1,4-bis[(trimethoxysilyl}methyl] piperazine (8) with 2-methyllactic acid (molar ratio 1:4) in water/acetone (yield 82\%). The molecular dinuclear silicon(IV) complex 6 contains two pentacoordinate (formally negatively charged) silicon atoms and two tetracoordinate (formally positively charged) nitrogen atoms. The crystal structure of 6•8H20 was studied by X-ray diffraction.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{MuehleisenTacke1994,
  author    = {M{\"u}hleisen, M. and Tacke, Reinhold},
  title     = {Twofold deprotonated citric acid as a bidentate ligand of pentacoordinate silicon: synthesis and structural characterization of the zwitterionic \(\lambda_5\)Si-spirosilicate bis[citrato(2-)-O\(^3\),O\(^4\)][(dimethylammonio)methyl]silicate hydrate},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64388},
  year      = {1994},
  abstract  = {The zwitterionic \(\lambda_5\) Si-spirosilicate bis[ citrato(2-)-0\(^3\) ,0\(^4\) )[ ( dimethylammonio) methyl]silicate (4) was synthesized by reaction of (MeO)\(_3\)SiCH\(_2\)NMe\(_2\) (3) with citric acid (molar ratio 1 :2) in acetonitrile at room temperature and isolated, after crystallization from water, as the hydrate 4 · H\(_2\)O (yield 81 \%). The crystal structure of 4 · H\(_2\)O was studied by single-crystal X-ray diffraction. The alcoxide oxygen atoms and central carboxylate oxygen atoms of two citrato(2-) ligands and one carbon atom coordinate to the silicon atom of 4 · H\(_2\)O. The coordination polyhedron around the pentacoordinate silicon atom (SiO\(_4\)C framework) can be described as a distorted trigonal bipyramid, the two carboxylate oxygen atoms occupying the axial sites. The \(\lambda_5\) Si~silicon(IV) complex 4 also exists in solution (DMSO, H\(_2\)O).},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeMuehleisen1994,
  author    = {Tacke, Reinhold and M{\"u}hleisen, M.},
  title     = {Hexacoordinate silicon in a compound with an F\(_5\)SiC unit},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64378},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeMuehleisen1994,
  author    = {Tacke, Reinhold and M{\"u}hleisen, M.},
  title     = {Hexakoordiniertes Silicium in einer molekularen Verbindung mit einer F\(_5\)SiC-Einheit},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64365},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeMuehleisenJones1994,
  author    = {Tacke, Reinhold and M{\"u}hleisen, M. and Jones, P. G.},
  title     = {The first zwitterionic, optically active disilicate with pentacoordinate silicon},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64358},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeMuehleisenJones1994,
  author    = {Tacke, Reinhold and M{\"u}hleisen, M. and Jones, P. G.},
  title     = {Das erste zwitterionische, optisch aktive Disilicat mit pentakoordiniertem Silicium},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64343},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeLopezMrasJones1994,
  author    = {Tacke, Reinhold and Lopez-Mras, A. and Jones, P. G.},
  title     = {Syntheses, crystal structure analyses, and NMR studies of [2-(dimethylammonio)phenyl]bis[glycolato(2-)-O1,O2]silicate and related zwitterionic spirocyclic \(\lambda_5\)Si-silicates},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64339},
  year      = {1994},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeSperlichBecker1994,
  author    = {Tacke, Reinhold and Sperlich, J. and Becker, B.},
  title     = {Bis[2,3-naphthalenediolato(2-)](pyrrolidinio-methyl)germanate-tetartoacetonitrile, the first zwitterionic \(\lambda_5\)-germanate: synthesis and crystal structure analysis},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64329},
  year      = {1994},
  abstract  = {The zwitterionic spirocyclic \(\lambda_5\)-germanate bis(2,3-naphthalenediolato( 2-)](pyrrolidiniomethyl)germanate (8) was synthesized and the crystal structure of its tetartoacetonitrile solvate 8 · 1/4 CH\(_3\)CN studied by single-crystal X-ray diffraction. Compound 8 was prepared by reaction of (MeO)\(_3\)GeCH\(_2\)NC\(_4\)H\(_8\) (11; NC\(_4\)H\(_8\) = pyrrolidino) with two equivalents of 2,3-naphthalenediol (isolated as 8 · 1/4 CH\(_3\)CN; yield 92\%). The coordination polyhedron around the pentacoordi- naphthalenediolatonate germanium atom of 8 · 1/4 CH\(_3\)CN can be described as a strongly distorted trigonal bipyramid (the structure is displaced by 38.9\% from the ideal trigonal bipyrarnid towards the ideal square pyramid), the carbon atom occupying an equatorial position. In the crystal lattice of 8 · 1/4 CH\(_3\)CN, the zwitterions form intermolecular N-H ... o hydrogen bonds leading to the formation of dimers. 1H- and \(^{13}\C-NMR studies revealed that 8 also exists in solution ([D\(_6\)]DMSO).},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeWagnerSperlich1994,
  author    = {Tacke, Reinhold and Wagner, S. A. and Sperlich, J.},
  title     = {Synthese von (-)-(Acetoxymethyl)(hydroxy-methyl)methyl(phenyl)german [(-)-MePhGe(CH\(_2\)OAc)(CH\(_2\)OH)] durch eine Esterase-katalysierte Umesterung: Die erste enzymatische Synthese eines optisch aktiven Germans},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64310},
  year      = {1994},
  abstract  = {No abstract available.},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackePikiesWiesenbergeretal.1994,
  author    = {Tacke, Reinhold and Pikies, J. and Wiesenberger, F. and Ernst, L. and Schomburg, D. and Waelbroeck, M. and Christophe, J. and Lambrecht, G. and Gross, J. and Mutschler, E.},
  title     = {Sila-biperiden und endo-Sila-biperiden: Synthesen, Kristallstrukturen und antimuscarinische Eigenschaften},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64303},
  year      = {1994},
  abstract  = {Starting from trichloro(vinyl)silane (Cl\(_3\)SiCH=CH\(_2\)), the musearinic antagonists sila-biperiden [rac-(SiRS,C2SR>-ao-2] and endosila- biperiden [rac-(SiRS,C2SR)-endo-2] were prepared by a seven-step synthesis. Both silanols are configurationally stableininert organic solvents but undergo slow epimerization in aqueous solution (pH 7.4, 32°C) by inversion of the configuration at the silicon atom. The relative configurations of sila-biperiden and endo-sila-biperiden were detennined by single-crystal X-ray diffraction. Both compounds form intennolecular 0-H · · · N hydrogen bonds in the crystal leading to the fonnation of centrosymmetric dimers (sila-biperiden) and infinite chains (endo-sila-biperiden), respectively. Sila-biperiden is a silicon analogue (C/Si exchange) of the antiparkinsonian drug biperiden [rac-(CRS/C2SR}-exo-1]. In functional phannacological experiments, as well as in radioligand competition studies, biperiden, sila-biperiden and endo-sila-biperiden behaved as simple competitive antagonists at muscarinic Ml-, M2-, M3- and M4-receptors. The three compounds displayed the highest affinity for Ml-receptors (pA\(_2\) values: 8.72-8.80; pK\(_i\) values: 8.8-9.1), intermediate affinity for M4- and M3-receptors, and lowest affinity for M2-receptors (pA\(_2\) values: 7.57-7.79; pK\(_i\) values: 7.7-7.8). The affinity profile (Ml >. M4 > M3 > M2) of biperiden, sila-biperiden and endo-sila-biperiden is qualitatively similar to that of the M1-selective muscarinic antagonist pirenzepine. The antimuscarinic properlies of the C/Si analogues biperiden and sila-biperiden are almost identical.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeWagnerBrakmannetal.1993,
  author    = {Tacke, Reinhold and Wagner, S. A. and Brakmann, S. and Wuttke, F. and Eilert, U. and Fischer, L. and Syldatk, C.},
  title     = {Synthesis of acetyldimethyl(phenyl)silane and its enantioselective conversion into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane by plant cell suspension culytures of Symphytum officinale L. and Ruta graveolens L.},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64299},
  year      = {1993},
  abstract  = {Starting from chlorodimethyl(phenyl)silane (3), acetyldimethyl(phenyl)silane (l) was prepared by a two-step synthesis in a total yield of 90\% [PhMe\(_2\)SiCl (3)-> PhMe\(_2\)SiCCOMe)=CH\(_2\) (4)-> PhMe\(_2\)SiC(O)Me (1)]. The prochiral acetylsilane 1 was transfonned enantioselectively into (R)-(1-hydroxyethyl)dimethyl(phenyl)silane [(R)-2] using plant cell Suspension cultures of Symphytum officinale L. or Ruta graveolens L. Under preparative conditions (300-mg scale, not optimized), (R)-2 was isolated in 15\% (Symphytum) and 9\% yield (Ruta), respectively. The enantiomeric purities of the products were 81\% ee (Syrnphytum) and 60\% ee (Ruta), respectively.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{EltzeUllrichMutschleretal.1993,
  author    = {Eltze, M. and Ullrich, B. and Mutschler, E. and Moser, U. and Bungardt, E. and Friebe, T. and Gubitz, C. and Tacke, Reinhold and Lambrecht, G.},
  title     = {Characterization of muscarinic receptors mediating vasodilation in rat perfused kidney},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64283},
  year      = {1993},
  abstract  = {The muscarinic receptor mediating vasodilation of resistance vessels in the rat isolated, constant-pressure perfused kidney (preconstriction by w- 7 M cirazoline) was characterized by subtype-preferring agonists and se]ective antagonists. The agonists produced vasodi1ation with the fol1owing rank order of potency: arecaidine propargy] ester (APE) > 5-methylfurtrethonium = methacholine = oxotremorine > (S)-aceclidine > arecaidine 2-butyne-1,4-diyl bisester > 4-Cl-McN-A-343 = (R)-nipecotic acid ethyl ester = N-ethyl-guvacine propargyl ester- (R)-aceclidine = (S)-nipecotic acid ethyl ester > McN-A-343. Agonist-induced vasodilation disappeared after destruction of the endothelium with detergent. Highly significant correlations of agonist potencies for vasodilation were found between rat kidney and guinea-pig ileum submucosal arterioles as weH as agonist potencies at smooth muscle muscarinic M\(_3\) receptors of the guinea-pig ileum. The rank order of antagonist potencies (4-diphenylacetoxy-Nmethylpiperidine methiodide (4-DAMP) > (R)-hexahydro-difenidol - hexahydro-sila-difenidol > pirenzepine - p-fluorohexahydro- sila-difenidol- himbacine- AF-DX 384- AQ-RA 741 > (S)-hexahydro-difenidol) to attenuate vasodilation to APE in rat kidney, correlated significantly with affinities at M\(_3\) receptors in submucosal arterioles and in smooth muscle of the guinea-pig ileum, but differed from those at M\(_1\) and M\(_2\) receptors in rabbit vas deferens. The agonist and antagonist potencies suggest that vasodilation elicited by muscarinic stimuli in endothelium-intact rat renal vasculature is mediated by functional muscarinic M\(_3\) receptors.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeBechtLopezMrasetal.1993,
  author    = {Tacke, Reinhold and Becht, J. and Lopez-Mras, A. and Sheldrick, W. S. and Sebald, A.},
  title     = {Syntheses, X-ray crystal structure analyses, and solid-state NMR studies of some zwitterionic organofluorosilicates},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64272},
  year      = {1993},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeLopezMrasBechtetal.1993,
  author    = {Tacke, Reinhold and Lopez-Mras, A. and Becht, J. and Sheldrick, W. S.},
  title     = {Synthese sowie Kristall- und Molek{\"u}lstruktur von Tetrafluoro[2-(pyrrolidinio)ethyl]silicat},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64269},
  year      = {1993},
  abstract  = {Das zwitterionische Tctratluoro[2-(pyrrolidinio) ethyl]silicat (4) wurde durch Reaktion von Trimethoxy( 2-pyrrolidinoethyl)silan (5) mit Fluorwasserstoff in einem Ethanol/Flußs{\"a}ure-Gemisch bei 0 °C synthetisiert. Die Kristall- und Molek{\"u}lstruktur von 4 wurde bei - 100 °C mittels einer Einkristall-R{\"o}ntgenstrukturanalyse untersucht. Außerdem wurde 4 durch NMR-Untersuchungen in L{\"o}sung charakterisiert (CD\(_3\)CN: \(^1\)H, \(^{13}\)C).},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeLopezMrasSperlichetal.1993,
  author    = {Tacke, Reinhold and Lopez-Mras, A. and Sperlich, J. and Strohmann, C. and Kuhs, W. F. and Mattern, G. and Sebald, A.},
  title     = {Neue zwitterionische \(\lambda_5\)-Spirosilicate: Synthesen, Einkristall-R{\"o}ntgenstrukturanalysen und Festk{\"o}rper-NMR-Untersuchungen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64251},
  year      = {1993},
  abstract  = {The zwitterionic spirocyclic \(\lambda_5\) -Silicates bis(3,4,5,6-tetrabromo- 1,2-benzenediolato(2- ))[2-(pyrrolidinio)ethyl]silicate (5; and its monohydrate 5 · H\(_2\)O) and bis[1,2-benzenediolato(2- )][( dimethylammonio)methyl]silicate (6) were synthesized by various methods including Si-C bond cleavage reactions. The crystal structures of 5, 5 · H\(_2\)O, and 6 were investigated by Xray d{\"u}fraction. Furthermore, 5, 5 · H\(_2\)O, 6, and the related zwitterionic \(\lambda_5\)-spirosilicates 1 · 1/4 CH\(_3\)CN, 2 · CH\(_3\)CN, 3 · CH\(_3\)CN, and 4 were characterized by solid-state NMR spectroscopy (\(^{29}\)Si and \(^{15}\)N CP/MAS). The pentacoordinate silicon atoms of 5, 5 · H\(_2\)O (two crystallographically independent ZWitterions and two crystallographically independent water molecules), and 6 (two crystallographically independent zwitterions) are surrounded by four oxygen atoms and one carbon atom. The coordination polyhedrons around the silicon atoms of 5 and 6 can be described as distorted (5) or nearly ideal (6) trigonal bipyramids, the carbon atoms being in equatorial positions. 5 forms intramolecular and 6 intermolecular (--+ formation of dimeric units) N- H···O hydrogen bonds. The coordination polyhedrons around the two crystallographically independent silicon atoms of 5 · H\(_2\)O can be described as a nearly ideal and slightly distorted square pyramid, respectively, the carbon atoms being in the apical positions. In the crystal lattice of 5 · H\(_2\)O, intermolecular N-H···O and 0-H···O hydrogen bonds between the zwitterions and water molecules are observed. The results obtained by X-ray diffraction and solid-state NMR spectroscopy are consistent for each compound studied.},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeLopezMrasSheldricketal.1993,
  author    = {Tacke, Reinhold and Lopez-Mras, A. and Sheldrick, W. S. and Sebald, A.},
  title     = {Synthesen, Einkristall-R{\"o}ntgenstrukturanalysen und \(^{29}\)Si-Festk{\"o}rper-NMR-Untersuchungen eines zwitter- ionischen \(\lambda_5\)-Spirosilicats und eines k{\"a}figartigen Octa(silasesquioxans) : [Professor Hartmut B{\"a}rnighausen zum 60. Geburtstage gewidmet]},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64243},
  year      = {1993},
  abstract  = {No abstract available},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{WaelbroeckCamusTastenoyetal.1992,
  author    = {Waelbroeck, M. and Camus, J. and Tastenoy, M. and Mutschler, E. and Strohmann, C. and Tacke, Reinhold and Schjelderup, L. and Aasen, A. and Lambrecht, G. and Christophe, J.},
  title     = {Stereoselective interaction of procyclidine, hexahydro-difenidol, hexbutinol and oxyphencyclimine, and of related antagonists, with four muscarinic receptors},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64237},
  year      = {1992},
  abstract  = {Wc invcstigatcd thc binding properlies of thc (R)- and (Sl-cnantiomcrs of thc muscarinic antagonists trihcxyphcnidyl, procyclidinc, hcxahydro-difcnidol. p-fluoro-hcxahydro-difcnidol. hcxbutinol, p-fluoro-hcxbutinnl. and thcir corrcsponding methiodidcs at muscarinic M\(_1\), M\(_2\)• M\(_3\) and M\(_4\) receptor subtypes. In addition. binding properlies of thc (R)- and (S)-cnantiomcrs of oxyphcncycliminc wcrc studicd. The {R)- cnantiomcrs (cutomcrs} of all the compounds had a grcatcr affinity than the (S)-isomcrs for thc four muscarinic rcccptor subtypcs. Thc binding pattcrns of thc (R)- and (S)-enantiomers wcrc gcncrally different. We did not obscrvc any gcncral corrclation hctwccn thc potcncy of thc high-affinity enantiomer and Lhc affinity ratio (cudismic ratio) of the two cnantiomcrs. Thc rcsuhs arc discusscd in tcrms of a 'four suhsitcs' binding modcl.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeBeckerBergetal.1992,
  author    = {Tacke, Reinhold and Becker, B. and Berg, D. and Brandes, W. and Dutzmann, S. and Schaller, S.},
  title     = {Bis(4-fluorophenyl)methyl(1H-1,2,4-triazol-1-yl-methyl)germane, a germanium analogue of the agricultural fungicide flusilazole: synthesis and biological properties},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64224},
  year      = {1992},
  abstract  = {Bis( 4-fluorophenyl)methyl(l H-1,2,4-triazol-1-yl-methyl)germane (2), a germanium analogue of the agricultural fungicide flusilazole (1), has been synthesized from Cl\(_3\)GeCH\(_2\)CI (3) by both a three-step and a four-step synthesis (3-> (p-F-C\(_6\)H\(_4\))\(_2\)Ge(CH\(_2\)Cl)Br (4)-> (p-F-C\(_6\)H\(_4\))\(_2\)Ge(CH\(_2\)CI)CH\(_3\) (S)-> 2; S ~ (p-F-C\(_6\)H\(_4\))\(_2\)Ge(CH\(_2\)I)CH\(_3\) (6)-> l). The fungicidal properties of l have been compared with those of the parent silicon compound 1 (studies on Si/Ge bioisosterism). In various test systems, the SijGe analogues 1 and 2 showed comparable fungicidal properlies (in activity against plant pathogenic fungi: in agar plate diffusion tests and greenhause evaluations; in activity against human pathogenic fungi: in serial dilution tests). In addition, 1 and 2 displayed comparable potencies in respect of sterol biosynthesis inhibition in Sacclulromycopsis {\"u}polytica and Pyricularia oryzae, the mode of action being primarily an inhtbition of oxidative C14-demethylation.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeBechtMatternetal.1992,
  author    = {Tacke, Reinhold and Becht, J. and Mattern, G. and Kuhs, W. F.},
  title     = {Zur Existenz zwitterionischer \(\lambda_5\)-(Ammonioorganyl)tetrafluorosilicate: Synthese sowie Kristall- und Molek{\"u}lstruktur von Tetrafluoro(pyrrolidiniomethyl)silicat},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64217},
  year      = {1992},
  abstract  = {The zwitterionic tetrafluoro(pyrrolidiniomethyl)silicate (6) was synthesized by the reaction of trimethoxy(pyrrolidinomethyl) silane (7) with hydrogen fluoride in ethanol/hydrofluoric acid (yield 83\%). 6 crystallizes in the space group P2\(_1\)fc with two crystallographically distinct molecules in the asymmetric unit. In both molecules the pentacoordinate silicon atom is surrounded by four fluorine atoms and one carbon atom, the latter being in an equatorial position. The coordination polyhedron of the silicon atoms can be described as a slightly distorted trigonal bipyramid. The zwitterionic structure was also proved for dissolved 6 (solution in CD\(_3\)CN, NMRspectroscopic studies).},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{BungardtVockertFeifeletal.1992,
  author    = {Bungardt, E. and Vockert, E. and Feifel, R. and Moser, U. and Tacke, Reinhold and Mutschler, E. and Lambrecht, G. and Suprenant, A.},
  title     = {Characterization of muscarinic receptors mediating vasodilation in guinea-pig ileum submucosal arterioles by the use of computer-assisted videomicroscopy},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64206},
  year      = {1992},
  abstract  = {Muscarinic receptors of rcsistance vessels (submucosal artcrioles, outside diametcr 50-75 J,Lm) from the guinea-pig small intestinc were invcstigatcd in vitro using a computcr-assisted vidcomicroscopy system (Diamtrak <~t ). The muscarinic receptor which mediates vasodilation of prccontractcd [U-46619 (300 nM) or (- )-noradrcnaline (1 0 J.L M)] artcriolcs was characterized with scveral muscarinic agonists and subtypc-sclectivc antagonists. Thc following agonists all produccd cquivalent maximum vasodilation (given in rank ordcr of potency): acctylcholinc = arccaidinc propargyl cstcr (APE) > oxotremorine = ( ± )-muscarinc = ( ± )-mcthacholinc > carbachol > 4-[[N-{4-chlorophenyl)carbamoyl]oxy]-2-hutynyltrimcthylammonium iodide (4-CI-McN-A- 343). 4-([N-(3-ChlorophcnyD-carbamoyl)oxy]-2-butynyltrimcthylammonium chloride (McN-A-343) and N-ethyl-guvacinc propargyl ester (NEN-APE) produccd minimal or no artcriolar vasodilation. Thc muscarinic antagonists pircnzcpinc, ( ± )-5,11-dihydro-11- [[[2-[2-((dipropylamino)methyl}-1-pipcridinyl]ethyl]amino ]-carbonyi]-6H-pyrido(2,3-h)( 1 ,4)-benzodiazcpin-6-onc (AF-DX 384 ), 11- [[ 4-[4-(dicthylamino)butyl]-1-piperidinyl]acetyl]-5, ll-dihydro-6H-pyrido(2.3-h)( 1,4 )-bcnzodiazepin-6-onc (AQ-RA 741 ), p-fluorohexahydro- sila-difcnidol (p-F-HHSiD), 4-diphcnylacetoxy-N-methylpipcridine mcthiodidc (4-DAMP) and (R)- and (S)hexahydro- difcnidol [(R)-HHD, (S)-HHD] shifted thc muscarinc, mcthacholinc or carbachol dosc-rcsponsc curve to the right in a compctitive manner. Schildanalysis of the data yicldcd pA\(_2\) valucs for pircnzcpinc (6.74/6.9), AF-DX 384 (6.72), AQ-RA 741 (6.58), p-F-HHSiD (7.53/7.57), 4-DAMP (9.06), (R)-HHD (7.88/8.32) and (S)-HHD (5.52/5.88). Thus, it can he concluded that submucosal arteriolcs posscss only the M\(_3\) functional muscarinic reccptor, the activation of which causcs hlood vcsscl dilation. The preparation dcscribcd is considcrcd to be a valuable now bioassay for pharmacological investigations of drug actions at muscarinic receptors in the peripheral vascular system.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeWiesenbergerBeckeretal.1992,
  author    = {Tacke, Reinhold and Wiesenberger, F. and Becker, B. and Rohr-Aehle, R. and Schneider, P. B. and Ulbrich, U. and Sarge, S. M. and Cammenga, H. K. and Koslowski, T. and Niessen, W. von},
  title     = {Ester von (Hydroxymethyl)diorganylsilanen: Synthese und thermisch induzierte Umlagerung},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64188},
  year      = {1992},
  abstract  = {Twenty silanes of the type R\(^1\)R\(^2\)Si(H)CH\(_2\)OR\(^3\) (A) were syn- and entropy of activation) of these reactions were studied by thesized {R\(^1\), R\(^2\) = Me, Ph, 1-naphthyl, PhCH\(_2\), Me\(_3\)SiCH\(_2\); OR\(^3\) means of d{\"u}ferential scanning calorimetry (DSC). In addition, = OC(O)Me, OC(O)Ph, OC(O)CF\(_3\) , OS(0)\(_2\)CF\(_3\), OP(O)Ph\(_2\), the kinetics of all reactions were investigated by 1H-NMR OC(O)Cl, and studied for their thermal behaviour. The silanes spectroscopy. The transition state of the rearrangement was A undergo a thermally induced rearrangement to give the investigated by an ab initio study based on the model comcorresponding silanes R\(^1\)R\(^2\)Si(OR\(^3\))Me (B). For compounds with pound H\(_3\)SiCH\(_2\)OC(O)H (-> MeH\(_2\)SiOC(O)H]. The theoretical OR3 = OC(O)Cl, an additional decarboxylation takes place to data and the experimentally obtained energetic and kinetic yield the chlorosilanes R1R2Si(Cl)Me. Except for the deriva- data are discussed in terms of mechanistic aspects of the retives with OR\(^3\) = OC(O)Cl, the energetic (reaction enthalpy) arrangement reaction A -> B. and kinetic data (reaction order, frequency factor, enthalpy ...},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeHengelsbergKlingneretal.1992,
  author    = {Tacke, Reinhold and Hengelsberg, H. and Klingner, E. and Henke, H.},
  title     = {Synthese der Si-funktionellen Acetylsilane tBu(Me\(_3\)SiCH\(_2\))[MeC(O)]SiF und tBu(Me\(_3\)SiCH\(_2\))[MeC(O)]SiH sowie Synthese und Kristallstruktur des Acetylsilanols tBu(Me\(_3\)SiCH\(_2\))[MeC(O)]SiOH: Substrate f{\"u}r mikrobielle Reduktionen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64192},
  year      = {1992},
  abstract  = {The racemic Si-functional acetylsilanes tBu(Me\(_3\)SiCH\(_2\))[ MeC(O)]SiF (1) and tBu(Me\(_3\)SiCH\(_2\))[MeC(O)]SiH (2) and the racemic acetylsilanol tBu(Me\(_3\)SiCH\(_2\))[MeC(O)]SiOH (3) were synthesized from Si(OMe)\(_4\) (4) as substrates for microbial reductions [4 -> tBuSi(OMe)\(_3\) (5) -> tBu(Me\(_3\)SiCH\(_2\))Si(OMe)\(_2\) (6) -> tBu(Me\(_3\)SiCH\(_2\))SiF\(_2\) (7)-> tBu(Me\(_3\)SiCH\(_2\))(CH\(_2\) = C(OMe))SiF (8) -> 1; 8 -> tBu(Me\(_3\)SiCH\(_2\))[CH\(_2\) = C(OMe)]SiH (9) -> 2; 6 -> tBu(Me\(_3\)SiCH\(_2\))[CH\(_2\) = C(OMe)]SiOMe (10) -> 3]. Compounds 1-3 were found to be reduced by cells of Trigonapsis variabilis (DSM 70714) ( = SiC(O)Me -> = SiCH(OH)Me}. The crystal and molecular structure of 3 was studied by singlecrystal X-ray diffraction. In the crystal, racemic 3 forms infinite chains built up by intermolecular 0-H .. ·O bonds between the hydroxyl and acetyl groups of molecules of the same absolute configuration.},
  subject      = {Anorganische Chemie},
  language  = {de}
}
@article{TackeMahnerStrohmannetal.1991,
  author    = {Tacke, Reinhold and Mahner, K. and Strohmann, C. and Forth, B. and Mutschler, E. and Friebe, T. and Lambrecht, G.},
  title     = {Cyclohexyl(4-fluorophenyl)(3-piperidinopropyl)silanol (p-fluoro-hexahydro-sila-difenidol, p-F-HHSiD) and derivatives: synthesis and antimuscarinic properties},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64162},
  year      = {1991},
  abstract  = {Four different syntheses of the potent and selective muscanruc antagonist cyclohexyl( 4- fluorophenyl)(3-piperidinopropyl)silanol ( p-fluoro-hexahydro-sila-difenidol, p-F-HHSiD (2b); isolated as hydrochloride 2b· HCl) are described (starting materials: (CH\(_3\)O)\(_2\)SiCH\(_2\)CH\(_2\)CH\(_2\)Cl and Si(OCH\(_3\))\(_4\) ). In addition, the synthesis of the corresponding carbon analogue p-fluoro-hexahydro-difenidol ( p-F-HHD (2a); isolated as 2a· HCI) and the syntheses of three p-F-HHSiD derivatives (3-5), with a modified cyclic amino group, are reported (3: piperidinojpyrrolidino exchange, isolated as 3· HCI; 4: piperidinoj hexamethylenimino exchange, isolated as 4 · HCl; 5: quaternization of 2b with methyl iodide). The chiral compounds 2a, 2b, 3, 4 and 5 were prepared as racemates. In functional pharmacological studies, 3-5 behaved as simple competitive antagonists at musearlnie Ml receptors in rabbit vas deferens, M2 receptors in guinea-pig atria, and M3 receptors in guinea-pig ileal smooth rnuscle. The pyrrolidino (3) and hexamethylenimino (4) analogues of the parent drug p-F-HHSiD (2b) displayed the highest affinity for Ml and M3 receptors (pA\(_2\) values: 7.0-7.4) but exhibited lower affinity for cardiac M2 receptors (pA\(_2\) : 5.9 and 6.0). Their affinity profile (Ml- M3 > M2) is different from that of p-F-HHSiD (2b) (M3 > Ml > M2), but qualitatively very similar tothat of p-F-HHD (2a). The methiodide 5 exhibited the highest affinity for Ml receptors (pA\(_2\) : 8.5) but lower affinity for M2 and M3 receptors by factors of 5.6 and 3.6, respectively.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{HengelsbergTackeFritscheetal.1991,
  author    = {Hengelsberg, H. and Tacke, Reinhold and Fritsche, K. and Syldatk, C. and Wagner, F.},
  title     = {Synthesis and enantioselective enzymatic hydrolysis of rac-dimethylphenyl[1-(phenylacetamido)- ethyl]silane},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64153},
  year      = {1991},
  abstract  = {Racemic dimethylphenyl(l-(phenylacetamido)ethyl)silane [rac-5) has been made by a four-step synthesis starting from (chloromethyl)dimethylphenylsilane [PhMe\(_2\)SiCH2Cl (1) ~ PhMe\(_2\)SiCH(Cl)Me (rac-2) - PhMe\(_2\)SiCH(l)Me (rac-3) - PhMe2SiCH(NH2)Me (rac-4) ~ PhMe\(_2\)SiCH[N(H)C(O)CH\(_2\)Ph]Me ( rac-5); total yield 41\% ). Enantioselective enzymatic hydrolysis of rac-5, catalyzed by immobilized penicillin G acylase (E.C. 3.5.1.11) from Escherichia coli 5K (pHM 12), gave (R)-(1- aminoethyl)dimethylphenylsilane [( R )-4] in 40\% yield with an enantiomeric purity of 92\% ee.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{StrohmannBauereckerCammengaetal.1991,
  author    = {Strohmann, C. and Bauerecker, S. and Cammenga, H. K. and Jones, P. G. and Mutschler, E. and Lambrecht, G. and Tacke, Reinhold},
  title     = {Enantiomers of the muscarinic antagonist 1-cyclohexyl-1-(4-fluorophenyl)-4-piperidino-1-butanol (p-fluoro-hexahydro-difenidol): synthesis, absolute configuration, and enantiomeric purity},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64144},
  year      = {1991},
  abstract  = {The enantiomers of the antimuscarinic agent 1-cyclohexyl-1- (4-fluorophenyl)-4-piperidino-1-butanol [(R)- and (S)-p-fluorohexahydro- difenidol] ((R)- and (S)-2a] and their methiodides (R)- 3 and (S)-3 were prepared with high enantiomeric purity. (R)- 2a and (S)-2a (isolated as hydrochlorides) were obtained by catalytic hydrogenation (Pd/C contact) of the corresponding enantiomers of 1-cyclohexyl-1-( 4-fl uorophen yl)-4-piperidino- 2-butyn-1-ol [(R)- and (S)-4]. Reaction of (R)-2a and (S)-2a with rnethyl iodide led to (R)-3 and (S)-3, respectively. The unsaturated precursors (R)- and (S}-4 (enantiorneric purity ~ 99.80 and ~99.94\% e.e.; calorimetric analysis) were prepared by res-sepaolution of rac-4 [available from 4-FC\(_6\)H\(_4\)C(O)C\(_6\)H\(_{11}\) by reaction with LiC ~ CCH\(_2\)NC\(_5\)H\(_{10}\)] using (R)- and (S)-mandelic acid as resolving agents. The absolute configurations of the (R) and (S) enantiomers of 2a, 3, and 4 were determined by an X-ray crystal-structure analysis of (S)-5, the methiodide of (S)-4. (R)- 2a and (R)-3 exhibit a higher affinity for muscarinic M1, M2, M3, and M4 receptors (by up to two orders of magnitude) than their corresponding antipodes (S)-2a and (S)-3, the degree of stereoselectivity depending on the receptor subtype involved. (R)-2a represents a useful tool for rnuscarinic receptor research (affinity profile: M1 ~ M3 ~ M4 > M2).},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{WaelbroeckCamusTastenoyetal.1991,
  author    = {Waelbroeck, M. and Camus, J. and Tastenoy, M. and Mutschler, E. and Strohmann, C. and Tacke, Reinhold and Lambrecht, G. and Christophe, J.},
  title     = {Stereoselectivity of (R)- and (S)-hexahydro-difenidol binding to neuroblastoma M\(_1\), cardiac M\(_2\), pancreatic M\(_3\), and striatum M\(_4\) muscarinic receptors},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64135},
  year      = {1991},
  abstract  = {(R)-Hexahydro-difenidol has a higher affinity for M\(_1\) receptors in NB-OK 1 cells, pancreas M\(_3\) and striatum M\(_4\) receptors (pKi 7.9 to 8.3) than for cardiac M2 receptors (pKi 7 .0). (8)-Hexahydro-difenidol, by contrast, is nonselective (pKi 5.8 to 6.1). Our goal in the present study was to evaluate the importance ofthe hydrophobic phenyl, and cyclohexyl rings of hexahydro-difenidol for the stereoselectivity and reeeptor selectivity of hexahydro-difenidol binding to the four muscarinic receptors. Our results indieated that replacement of the phenyl ring of hexahydro-difenidol by a cyclohexyl group <~ dicyclidol) and ofthe cyclohexyl ring by a phenyl moiety <~ difenidol) indueed a !arge (4- to 80-fold) decrease in binding affinity for all musearlnie receptors. Difenidol had a signifieant preference for M\(_1\) , M\(_3\) , and M\(_4\) over M\(_2\) receptors; dicyclidol, by eontrast, had a greater affinity for M\(_1\) and M\(_4\) than for M\(_2\) and M\(_3\) receptors. The binding free energy deerease due to replacement ofthe phenyl and the cyelohexyl groups of(R)-hexahydro-difenidol by, respectively, a eyclohexyl and a phenyl moiety was almostadditive in the ease of M\(_4\) (striatum) binding sites. In the ease ofthe cardiac M\(_2\), pancreatic M\(_3\) , or NB-OK 1 M\(_1\) receptors the respective binding free energies were not eompletely additive. These results suggest that the four (R)-hexahydro-difenidol ''binding moieties" (phenyl, cyclohexyl, hydroxy, and protonated amino group) cannot simultaneously form optimal interaetions with the M\(_1\), M\(_2\), and M\(_3\) muscarinic receptors. When eaeh of the hydrophobic groups is modified, the position of the whole molecule, relative to the four subsites, was changed to allow an optimal overall interaction with the musearlnie receptor.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{WaelbroeckCamusTastenoyetal.1991,
  author    = {Waelbroeck, M. and Camus, J. and Tastenoy, M. and Mutschler, E. and Strohmann, C. and Tacke, Reinhold and Lambrecht, G. and Christophe, J.},
  title     = {Binding affinities of hexahydro-difenidol and hexahydro-sila-difenidol analogues at four muscarinic receptor subtypes: constitutional and stereochemical aspects},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64128},
  year      = {1991},
  abstract  = {Hexahydro-sila-difenidoJ and eight analogues behaved as simple cumpetitive inhibitors of eHJN·methyl·scopoJamine binding to homogenates frorn human neuroblastoma NB-OK 1 cells (M\(_1\) sites), rat heart (M\(_2\) sites), rat pancreas (M\(_3\) sites), and rat striatum 'B' sites (M\(_4\) sites). Pyrrolidino- and hexamethyleneimino analogues showed the same sekctivity profile as the parent compound. Hexahydro-sila-difenidol methiodide and the methiodide of p-fluoro-hexahydro·sila-difenidol had a f{\"u}gher affinity but a lower selectivity than the tertiary amines. Compounds containing a p·methoxy, p-chJoro or p-fluoro substituent in the phenyl ring of hexahydro-sila-difenidol showed a qualitative)y similar selectivity profile as the parent compound (i.e., M\(_1\)= M\(_3\) = M\(_4\) >M\(_2\) ), but up to 16-fold lower affinities. o-Methoxy-hexahydro-sila-difenidol has a lower affinity than hexahydro-sila-difeni.:!o! at the four binding sites. lts selectivity profile (M\(_4\) > M\(_1\), M\(_3\) > M\(_2\) ) was different from hexahydro-sila-difenidol. Replacement of the centrat silicon atom of hexahydro-sila-difenidol, p-fluoro-hexahydro-sila-difenidol and thdr quatemary (N-methylated) analogues by a carbon atom did not change their binding affinities significantly. The iour muscarinic receptors showed a higher affinity for the (R)- than for the (S)-enantiomers of hexahydro-difenidol, p-fluorohexahydro-difenidol and their methiodides. The stereoselectivity varied depending on the receptor subtype and drug considered.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{DoerjeWessLambrechtetal.1991,
  author    = {D{\"o}rje, F. and Wess, J. and Lambrecht, G. and Tacke, Reinhold and Mutschler, E. and Brann, M. R.},
  title     = {Antagonist binding profiles of five cloned human muscarinic receptor subtypes},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64113},
  year      = {1991},
  abstract  = {A variety of muscarinic antagonists are currently used as tools to pharmacologically subclassify muscarinic receptors into M\(_1\), M\(_2\) and M\(_3\) subtypes. ln the present study I we have determined the affinity proflies of several of these antagonists at five cloned human muscarinic receptors (m1-m5) stably expressed in Chinesehamster ovary cells (CHO-K1). At all five receptorsl the (R)-enantiomers of trihexyphenidyl and hexbutinol displayed considerably higher affinities (up to 525-fold) than their corresponding (S)-isomers. The stereoselectivity ratios [inhibition constant( S)/inhibition constant(R)] for both pairs of enantiomers were lowest at m2 receptors, suggesting that less stringent configurational demands are made by this receptor subtype. The "M\(_1\)-selective" antagonist (R)-trihexyphenidyl displayed high affinities for m1 and m4 receptors. The "M\(_2\)-selective" antagonists himbacinel (±}-5, 11-dihydro-11-1[(2-[(dipropylamino)methyl]-1- piperidinyllethyl)amino]carbonyii-6H-pyrido(213-b)(1 ~4)benzodiazepine- 6-one (AF-DX 384)1 11-(14-[4-(diethylamino)butyl)-1-piperidinyll acetyl)-5~ 11-dihydro-6H-pyrido(2~3-b) (1~4)benzodiazepine-6-one (AQ-RA 741) and (+K11-(12-[(diethylamino)methyl]-1-piperidinyll acetyl)-5~ 11-di-hydro-6H-pyrido(2~3-b)(1,4)benzodiazepine-6-one (AF-OX 250; the (+)-enantiomer of AF-DX 116] exhibited high affinities for m2 and m41 intermediate affinities for m1 and m3 and low affinities for m5 receptors. This selectivity profile was most prominent for AQ-RA 7 41 I which displayed 195- and 129-fold higher affinities for m2 and m4 receptors than for mS receptors. The "M\(_3\)-selective" antagonist (±)-p-fluoro-hexahydro-sila-difenidol hydrochloride (pFHHsiD) exhibited high affinity for m1 I m3 and m4 receptors. 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) bound with up to 7 -fold higher affinities to m1 I m31 m4 and m5 receptors than to m2 receptors. Although none of the tested antagonists showed more than 2-fold selectivity for one subtype over all other subtypes, each receptor displayed a unique antagonist binding profile.},
  subject      = {Anorganische Chemie},
  language  = {en}
}
@article{TackeBrakmannWuttkeetal.1991,
  author    = {Tacke, Reinhold and Brakmann, S. and Wuttke, F. and Fooladi, J. and Syldatk, C. and Schomburg, D.},
  title     = {Stereoselective microbial reduction of racemic acetyl(t-butyl)methylphenylsilane by Trigonopsis variabilis (DSM 70714) and Corynebacterium dioxydans (ATCC 21766)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64109},
  year      = {1991},
  abstract  = {(SiR,CR)- and (SiS,CR)-t-butyl(l-hydroxyethyl)methylphenylsilane [(SiR,CR)-2 and (SiS,CR)-3] have been prepared by (R)-selective microbial rcduction of racemic acetyl(t-butyl)methylphenylsilane (rac-1) using resting free cells of the yeast Trigonopsis variabilis (DSM 70714) or the bacterium Corynebacterium dioxydans (ATCC 21766). The biotransfonnations were carried out on a 10 g scale. Afterseparation by column chromatography on silica gel, the optically active diastereomers (SiR,CR)-2 and (SiS,CR)-3 produccd by T. variabilis were obtained in good yields [74\% ((SiR,CR)-2). 78\% ((SiS,CR)-3)]. The products obtained from the reduction with C. dioxydans were isolated in significantly lower yields [20\% ((SiR,CR)-2), 20\% ((SiS,CR)-3)]; reaction conditions not optimized). Both bioconversions gave products with high enantiomeric purities (T. variabilis: 91\% ee ((SiR,CR)-2), 96\% ee ((SiS,CR)-3); C. dioxydons: ~ 991 ee ((SiR,CR)-l), ~ 99\% ee ((SiS,CR)-3)). To throw light on the stereochemical aspects of these biotransfonnations, an X-ray diffraction study was carried out on the 3,5-dinitrobenzoate of rac-(SiR,CS/SiS,CR)-3. In addition, 1H NMR spectroscopic stereochemical correlation studies were performed with the (S)-MTPA esters derived from (SiR,CR)-l, (SiS,CR)-3, rac-(SiR,CRjSiS,CS)-2 and rac-(SiR,CSjSiS,CR)-3 [rac-(SiR,CR/ SiS,CS)-2 and rac-(SiR,CS/SiS,CR)-3 were obtained by reduction of rac-1 with LiAIH\(_4\) in diethylether, followed by chromatographic separation of the diastereomers on silica gel]. These stereochemical studies allowed assignment of the absolute configurations and enantiomeric purities of the biotransformation products.},
  subject      = {Anorganische Chemie},
  language  = {en}
}