TY - JOUR A1 - Tacke, Reinhold A1 - Sperlich, J. A1 - Becker, B. T1 - Bis[2,3-naphthalenediolato(2-)](pyrrolidinio-methyl)germanate-tetartoacetonitrile, the first zwitterionic \(\lambda_5\)-germanate: synthesis and crystal structure analysis N2 - 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). KW - Anorganische Chemie KW - Lambda5-Germanate KW - zwitterionic KW - Germanium KW - pentacoordinate Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64329 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Saad, S. M. T1 - Silylation of cellulose N2 - 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. KW - Anorganische Chemie Y1 - 1977 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78368 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Rohr-Aehle, R. T1 - Ester des (Hydroxymethyl)[(trimethylsilyl)methyl]silans: Synthese und thermisch induzierte Umlagerung N2 - 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 gemäß einer Kinetik 1. Ordnung mit Halbwertszeiten von 10.0 bzw. 3.6 h (135 ° C, in C\(_6\)D\(_6\)). N2 - The synthesis of (hydroxymethyl)[(trimethylsilyl)methyl]silane (3) and that of the corresponding acetate 4 and chloroformiate 6 are described. 4 and 6 undergo a thermally induced rearrangement to give the difunctional silanes 5 and 8, respectively. The transformations 4 -> 5 and 6 -> 8 follow a first order rate law with half life times of 10.0 and 3.6 h, respectively (135 o C, in C\(_6\)D\(_6\) ). KW - Anorganische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63889 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Rafeiner, K. A1 - Strohmann, C. A1 - Mutschler, E. A1 - Lambrecht, G. T1 - Synthesis of the selective antimuscarinic agent 4-{[cyclohexylhydroxy(2-methoxyphenyl)silyl]methyl}-1,1-dimethylpiperazinium methyl sulfate (o-methoxy-sila-hexocyclium methyl sulfate) N2 - 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. KW - Anorganische Chemie KW - o-methoxy-sila-hexocyclium KW - silahexocyclium KW - sila-drugs KW - antimuscarinics KW - muscarinic receptor subtypes Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63930 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Pikies, J. A1 - Wiesenberger, F. A1 - Ernst, L. A1 - Schomburg, D. A1 - Waelbroeck, M. A1 - Christophe, J. A1 - Lambrecht, G. A1 - Gross, J. A1 - Mutschler, E. T1 - Sila-biperiden und endo-Sila-biperiden: Synthesen, Kristallstrukturen und antimuscarinische Eigenschaften N2 - 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. N2 - Die Antimuscarinica Sila-biperiden [rac-(SiRS,C2SR)-exo-2] und endo-Sila-biperiden [rac-(SiRS,C2SR)-endo-2] wurden ausgehend von Trichlor(vinyl)silan (Cl\(_3\)SiCH=CH\(_2\)) durch eine siebenstufige Synthese dargestellt. Die beiden Silanoie sind in inerten organischen Solvenzien konfigurationsstabil, unterliegen aber in wässeriger Lösung (pH 7.4, 3ZOC) einer Epimerisierung durch Inversion der Konfiguration am Silicium-Atom. Die relativen Konfigurationen von Sila-biperiden und endo-Sila-biperiden wurden durch Einkristall-Röntgenstrukturanalysen bestimmt. Beide Verbindungen bilden im Kristall intermolekulare 0-H · · · N-Wasserstoff- Brückenbindungen aus, die zum Aufbau von zentrosymmetrischen Dimeren (Sila-biperiden) bzw. unendlichen Ketten (endo-Sila-biperiden) führen. Sila-biperiden ist ein Silicium-Analogon (C/Si-Austausch) des Antiparkinsonmittels Biperiden [rac-(CRS,C2SR>-ao-1). Sowohl in funktionellen pharmakologischen Untersuchungen als auch in Radioligand-Kompetitionsexperimenten erwiesen sich Biperiden, Sila-biperiden und endo-Sila-biperiden als rein kompetitive Antagonisten an muscarinischen M1-, M2-, M3- und M4-Rezeptoren. Alle drei Verbindungen zeigten die höchste Affinität zu den Mt-Rezeptoren (pA\(_2\)-Werte: 8.72-8.80; pKrWerte: 8.8-9.1), eine deutlich geringere Affinität zu den M4- und M3-Rezeptoren und die niedrigste Affinität zu den kardialen M2-Rezeptoren (pA\(_2\)-Werte: 7.57-7.79; pKi-Werte: 7.7-7.8). Das Affinitätsprofil (Ml > M4 > M3 > M2) von Biperiden, Sila-biperiden und endo-Sila-biperiden ist dem des Mt-selektiven Antimuscarinicums Pirenzepin qualitativ sehr ähnlich. Die antimuscarinischen Eigenschaften der C/Si-Analoga Biperiden und Sila-biperiden sind nahezu identisch. KW - Anorganische Chemie KW - Silicon KW - Silanol KW - Sila-biperiden KW - Bioorganosilicon chemistry KW - Muscarinic antagonist KW - Muscarinic receptor subtype Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64303 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Pikies, J. A1 - Linoh, H. A1 - Rohr-Aehle, R. A1 - Gönne, S. T1 - Sila-Procyclidin: Eine neue Synthese sowie Untersuchungen zur peripheren und zentralen anticholinergen Wirkung N2 - 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) überlegen ist. N2 - Starting with Cl\(_3\)SiCH\(_2\)Cl. sila-procycUdine (I b) as well as its derivatives 2b (sila-trihexyphenidyl), 3b, and 4b (sila-cycrimine) were prepared by a new six-step synthesis witb a total yield of 16 (lb), 19 (2b), 8 (31) aud 7% (4b), respectively. - Comparative in vivo investigations (mice per os administration) with respect to the peripheral and centrat anticholinergic activity bavc shown that the silicon compound 1 b is advantageous over the c:arbon aualogue t a (procyclidine). KW - Anorganische Chemie Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63815 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Niedner, R. A1 - Frohnecke, J. A1 - Ernst, L. A1 - Sheldrick, W. S. T1 - Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, II T1 - Preparation and Properties of Silicon Compounds withPotential Curare-Like Activity, II N2 - Die potentiell curarewirksamen Silicium-Verbindungen Sa, Sc, Sd, Sg, Sh und 9a-9d wurden dargestellt. \(^1\)H-NMR-spektroskopische Untersuchungen ergaben Informationen über die Konformationen von 5 a- Sc in Lösung. Die Kristall- und Molekülstruktur von 5 c wurde röntgenstrukturanalytisch 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-Abstände diskutiert. N2 - 'The potential curare-like silicon compounds Sa, Sc, Sd, Sg, Sb, and 9a-9d were synthesized. \(^1\)H-NMR spectroscopic investigations provided information about the conformations of Sa-Sc in solution. The crystal and molecular structures 5 c were determined by X-ray structural analysis. The muscle relaxing properties of Sa-Sb and 9a-9d were investigated comparatively on mice (i. v., LD50 values). The observed structure-activity relationships are discussed with respect to the different covalent radii of the carbon and silicon atoms and the N ... N distances resulting therefrom. KW - Anorganische Chemie Y1 - 1980 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63670 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Niederer, Reinhold T1 - Sila-Pharmaka, 9. Mitt. [1] Darstellung und Eigenschaften potentiell curarewirksamer Silicium-Verbindungen, I T1 - Sila-Drugs, 9th Communication [1] Preparation and Properties of Silicon Compounds with Potential Curare-Like Activity, I JF - Zeitschrift für Naturforschung B N2 - 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. KW - curare-like activity KW - toxicological properties KW - pharmacological properties KW - silicon compounds Y1 - 1978 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128277 VL - 33 IS - 4 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Mühleisen, M. A1 - Jones, P. G. T1 - Das erste zwitterionische, optisch aktive Disilicat mit pentakoordiniertem Silicium N2 - No abstract available KW - Anorganische Chemie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64343 ER - TY - JOUR A1 - Tacke, Reinhold A1 - Mühleisen, M. A1 - Jones, P. G. T1 - The first zwitterionic, optically active disilicate with pentacoordinate silicon N2 - No abstract available KW - Anorganische Chemie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64358 ER -