TY - JOUR A1 - Sperlich, Jörg A1 - Becht, Joachim A1 - Mühleisen, Mathias A1 - Wagner, Stephan A. A1 - Mattern, Günter A1 - Tacke, Reinhold T1 - Zwitterionische Bis[vic-arendiolato(2-)][(morpholinio)alkyl]silicate: Synthese sowie strukturelle Charakterisierung in Lösung und im Kristall N2 - No abstract available. KW - Silicate KW - Bis[1,2-benzendiolato(2-)][(morpholinio)alkyl]silicates KW - Bis[2,3-naphthalenediolato(2-)][(morpholinio)alkyl]silicates KW - Zwitterionic [lambda]5-Spirosilicates Y1 - 1993 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-73153 ER - TY - JOUR A1 - Sheldrick, W. S. A1 - Linoh, H. A1 - Tacke, Reinhold A1 - Lambrecht, G. A1 - Moser, U. A1 - Mutschler, E. T1 - Crystal and molecular structures of the (R)-enantiomer and the racemate of the antimuscarinic agent (cyclohexyl)phenyl[2-(pyrrolidin-1-yl)ethyl]silanol (sila-procyclidine) N2 - The crystal structures of the (R)-enantiomer (2b) and the racemate (1 b) of (cyclohexyl)phenyl[2- (pyrrolidin-1-yl)ethyl]silanol (sila--procyclidine) have been determined by X -ray structural analysis. The absolute configuration of (2b) was established. (2b) crystallizes in the orthorhombic space group P2\(_1\)2\(_1\)2\(_1\), with a = 15.221 (1 ), b = 17.967(1 ), c = 6.463(1) A, and Z = 4. (1 b) crystallizes in the monoclinic space group P2\(_1\)/c, with a = 6.441 (1 ), b = 17.1 82(7), c = 16.707(4) A, ß = 1 03.86(2r, and Z = 4. The structures were refined to respective R factors of 0.044 and 0.058. The molecular conformation of sila-procyclidine is identical in the two different structures. lntermolecular 0-H • • • N hydrogen bonding is observed in both crystallattices.ln (1 b) (R)- and (S)-configurated molecules form centrosymmetric dimers, in (2b) the (R)-configurated molecules are linked into infinite chains parallel to the c axis. The (R)-configurated sila--procyclidine (2b) has higher affinity for ileal and atrial muscarinic receptors of the guinea pig than the (S)-configurated enantiomer (3b). KW - Anorganische Chemie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63776 ER - TY - JOUR A1 - Schomburg, D. A1 - Link, M. A1 - Linoh, H. A1 - Tacke, Reinhold T1 - Molekülstruktur der Akarizide Chlortrineophylstannan, Chlortris[(dimethylphenylsilyl)methyl]stannan und Trineophyl(1,2,4-triazol-1-yl)stannan-hemihydrat sowie des 2,5-Dimethyl-2,5-diphenylhexans (Bineophyl) N2 - Die Kristall- und Molekülstrukturen der Akarizide Chlortrineophylstannan (Ia), Chlortris[ ( dimethylphenylsilyl)methyl]stannan (tb) und Trineophyl(1,2,4-triazol-1- yl)stannan-hemihydrat (2a · 0.5H\(_2\)0) wurden durch Einkristall-Röntgenstrukturanalysen bestimmt. Zu V ergleichszwecken wurde ausserdem die Struktur des 2,5-Dimethyl-2,5-diphenylhexans (Bineophyl, 4) untersucht. Die Knüpfung von drei sehr raumerfüllenden N eophyl-Resten an ein Zinnatom führt zu einer deutlichen Verzerrung der tetraedrischen Geometrie [ta: C-Sn-C 117.2°, C-Sn-Cl99.7°; 2a·0.5H20: C-Sn-C 116.9° (Mittelwert), C-Sn-N 100.2° (Mittelwert)]. Austausch der zentralen Kohlenstoffatome in den Neophyt-Substituenten von la durch Siliciumatome führt zu einer Verringerung des Raumbedarfs und dadurch zu einer erkennbaren Angleichung an die tetraedrische Geometrie [lb: C-Sn-C 113.3° (Mittelwert), C-Sn-Cl 105.3° (Mittelwert)]. N2 - The crystal and molecular structures of the acaricides chlorotrineophylstannane (ta), chlorotris[( dimethylphenylsilyl)methyl]stannane (tb ), and trineophyl(1,2,4-triazol- 1-yl)stannane hemihydrate (2a · 0.5H\(_2\)0), have been determined by single-crystal X-ray diffraction studies. The structure of 2,5-dimethyl-2,5-diphenylhexane (4) was also investigated for comparison. Binding of three very bulky neophyl ligands around tin causes serious distortion of the tetrahedral geometry [la: C-Sn-C 117.2°, C-Sn-Cl 99.7°; la · 0.5H20: C-Sn-C 116.9° (mean), C-Sn-N 100.2° (mean)]. Replacement of the central carbon atoms in the neophyl substituents of ta by silicon atoms Ieads to a decrease in steric strain and hence to a much smaller distortion of the tetrahedral geometry [lb: C-Sn-C 113.3° (mean), C-Sn-Cl105.3° (mean)]. KW - Anorganische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63840 ER - TY - JOUR A1 - Sarge, S. A1 - Cammenga, H. K. A1 - Becker, B. A1 - Rohr-Aehle, R. A1 - Tacke, Reinhold T1 - Energetic and kinetic investigation of thermally induced molecular rearrangements of esters of (hydroxymethyl)hydridosilanes by DSC N2 - No abstract available KW - Anorganische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63850 ER - TY - JOUR A1 - Saad, S. M. A1 - Tacke, Reinhold T1 - 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) N2 - No abstract available. KW - Anorganische Analyse Y1 - 1977 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86958 ER - TY - JOUR A1 - Rettenmayr, N. M. A1 - Rodrigues de Miranda, J. F. A1 - Rijntjes, N. V. M. A1 - Russel, F. G. M. A1 - van Ginneken, C. A. M. A1 - Strohmann, C. A1 - Tacke, Reinhold A1 - Lambrecht, G. A1 - Mutschler, E. T1 - Pharmacokinetic properties of the antimuscarinic drug [\(^3\)H]-hexahydro-sila-difenidol in the rat N2 - The pharmacokinetics of tritiated hexahydrosila- difenidol ([\(^3\)H]-HHSiD) were examined in rats. Furthermore, the distribution of radioactivity was studied by means of whole body autoradiography. After i. v. administration of 2.9 mg/kg HHSiD plus [\(^3\)H]-HHSiD to anaesthetized rats bearing a catheter implanted in the ductus choledochus and receiving a mannitol infusion, HHSiD was rapidly distributed and metabolized. Only 5% ofthe radioactivity was recovered in blood after 23 s and 0.4% after 2.5 h. 64% of the plasma radioactivity could be extracted with hexane from the samples taken 23 s after administration. 52% of the radioactivity was eliminated within 2.5 h, 13% by urinary and 39% by biliary excretion. Following oral administration of 8.6 mg/kg HHSiD plus [\(^3\)H]-HHSiD there was an absorption of approximately one fourth of the administered radioactivity within 4 h. By means of whole body autoradiography (i. v. injection) as well as by tissue distribution measurement the highest Ievels of radioactivity were found in bile, urine, lung, kidney, adrenals, liver and .pancreas. Thus, after i. v. administration to rats HHSiD is rather quickly distributed, metabolized and excreted. This explains its low antimuscarinic potency in vivo. KW - Anorganische Chemie KW - Pharmacokinetics KW - [3H]-Hexahydro-siladifenidol KW - Sila-drug KW - Rat KW - Autoradiography Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64022 ER - TY - JOUR A1 - Polidori, C. A1 - Massi, M. A1 - Lambrecht, G. A1 - Mutschler, E. A1 - Tacke, Reinhold A1 - Melchiorre, C. T1 - Selective antagonists provide evidence that M\(_1\) muscarinic receptors may mediate carbachol-induced drinking in the rat N2 - The present study served to investigate the ability of seven selective muscarinic antagonists to inhibit carbachol-induced drinking in the rat. The muscarinic antagonists were given by intracerebroventricular (i.c.v.) injection 1 min before the i.c.v. injection of carbachol (1 \(\mu\)g/rat). The M\(_2\) antagonist, methoctramine, was inactive up to 80.3 nmol/rat. The M\(_3\) antagonist, p-fluoro-hexahydro-sila-difenidol, elicited a modest (42%) but statistically significant inhibition of drinking only at 80 nmol/rat. On the other band, the selective M\(_1\) antagonists, (R)-trihexyphenidyl, o-methoxy-sila-hexocyclium and pirenzepine, produced a marked and dose-dependent inhibition of carbachol-induced drinking, their 1050 values being 0.51. 7.36 and 9.31 nmoljrat. Also the M\(_1\)/M\(_3\) antagonists, 4-diphenylacetoxy-Nmethylpiperidine methiodide and hexahydro-sila-difen.idol, were potent inhibitors of carbachol-induced drinking, their ID\(_50\) values (0.28 and 11.09 nmoljrat) being related to their pA\(_2\) values for M1 receptors in rabbi t vas deferens. These data suggest that carbachol-induced drinking may be mediated by activation of muscarinic M\(_1\) receptors. KW - Anorganische Chemie KW - Carbachol-induced drinking KW - Muscarinic receptor antagonists KW - Muscarinic receptor subtypes KW - Muscarinic M1 receptors; Muscarinic M2 receptors Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64044 ER - TY - JOUR A1 - Mühleisen, M. A1 - Tacke, Reinhold T1 - 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 N2 - 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). KW - Anorganische Chemie KW - Silicon KW - pentacoordinate KW - Lambda5Si-Spirosilicate KW - zwitterionic KW - Citrato(2-)-03 KW - 04ligand Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64388 ER - TY - JOUR A1 - Mühleisen, M. A1 - Tacke, Reinhold T1 - 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 N2 - 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. KW - Anorganische Chemie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64396 ER - TY - JOUR A1 - Lambrecht, G. A1 - Gmelin, G. A1 - Rafeiner, K. A1 - Strohmann, C. A1 - Tacke, Reinhold A1 - Mutschler, E. T1 - o-Methoxy-sila-hexocyclium: a new quaternary M\(_1\)-selective muscarinic antagonist N2 - No abstract available KW - Anorganische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63862 ER -