@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{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{TackeRohrAehle1988, author = {Tacke, Reinhold and Rohr-Aehle, R.}, title = {Ester des (Hydroxymethyl)[(trimethylsilyl)methyl]silans: Synthese und thermisch induzierte Umlagerung}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63889}, year = {1988}, abstract = {Die Synthese des (Hydroxymethyl)[(trimethylsilyl)methyl]silans (3) sowie des hiervon abzuleitenden Acetats 4 und Chlorformiats 6 wird beschrieben. 4 und 6 unterliegen einer thermisch induzierten Umwandlung zu den difunktionellen Silanen 5 bzw. 8. Die Umwandlungen 4 -> 5 und 6 -> 8 erfolgen gem{\"a}ß einer Kinetik 1. Ordnung mit Halbwertszeiten von 10.0 bzw. 3.6 h (135 ° C, in C\(_6\)D\(_6\)).}, subject = {Anorganische Chemie}, language = {de} } @article{TackeRafeinerStrohmannetal.1989, author = {Tacke, Reinhold and Rafeiner, K. and Strohmann, C. and Mutschler, E. and Lambrecht, G.}, title = {Synthesis of the selective antimuscarinic agent 4-{[cyclohexylhydroxy(2-methoxyphenyl)silyl]methyl}-1,1-dimethylpiperazinium methyl sulfate (o-methoxy-sila-hexocyclium methyl sulfate)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63930}, year = {1989}, abstract = {The synthesis of the potent and highly selective silicon-containing antimuscarinic agent o-methoxysila- hexocyclium methyl sulfate and its corresponding tertiary amine (isolated as the dihydrochloride) is described. The quarternary compound is an omethoxy derivative of sila-hexocyclium methyl sulfate, which represents one of the tools currently used in experimental pharmacology for the subclassification of muscarinic receptors. The omethoxy derivative, the pharmacological profile of which differs substantially from tbat of the nonmethoxy compound, is also recommended as a tool for the investigation of muscarinic receptor heterogeneity.}, subject = {Anorganische Chemie}, language = {en} } @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{TackePikiesLinohetal.1987, author = {Tacke, Reinhold and Pikies, J. and Linoh, H. and Rohr-Aehle, R. and G{\"o}nne, S.}, title = {Sila-Procyclidin: Eine neue Synthese sowie Untersuchungen zur peripheren und zentralen anticholinergen Wirkung}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63815}, year = {1987}, abstract = {Sila-Procyclidin (1 b) sowie dessen Derivate 2b (Sila-Tribexyphenidyl), 3b und 4b (Sila-Cycrimin) wurden - ausgehend von Cl\(_3\)SiCH\(_2\)Cl - durch eine neue, sechsstufige Synthese mit einer Gesamtausbeute von 16 (lb), t9 (2b), 8 (3b) bzw. 7\% (4b) dar· gestellt. - Vergleichende in-vivo-Untcrsuchungen (Maus, per-osApplikation) hinsichtlich der peripheren und zentralen auticholincrgen Wirkung haben gezeigt, daß die Silicium-Verbindung 1 b dem Kohlenstoff-Analogon Ia (Procyclidin) {\"u}berlegen ist.}, subject = {Anorganische Chemie}, language = {de} } @article{TackeNiednerFrohneckeetal.1980, author = {Tacke, Reinhold and Niedner, R. and Frohnecke, J. and Ernst, L. and Sheldrick, W. S.}, title = {Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, II}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-63670}, year = {1980}, abstract = {Die potentiell curarewirksamen Silicium-Verbindungen Sa, Sc, Sd, Sg, Sh und 9a-9d wurden dargestellt. \(^1\)H-NMR-spektroskopische Untersuchungen ergaben Informationen {\"u}ber die Konformationen von 5 a- Sc in L{\"o}sung. Die Kristall- und Molek{\"u}lstruktur von 5 c wurde r{\"o}ntgenstrukturanalytisch bestimmt. Die muskelrelaxierenden Eigenschaften von S a- 5 h und 9 a-9 d wurden vergleichend an der Maus (i.v., LD50-Werte) untersucht. Die ermittelten Struktur-WirkungsBeziehungen werden in Hinblick auf die unterschiedlichen kovalenten Radien des Kohlenstoffund Siliciumatoms und die hieraus resultierenden N ... N-Abst{\"a}nde diskutiert.}, subject = {Anorganische Chemie}, 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{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{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} }