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 - 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 - TY - JOUR A1 - Lambrecht, G. A1 - Feifel, R. A1 - Forth, B. A1 - Strohmann, C. A1 - Tacke, Reinhold A1 - Mutschler, E. T1 - p-Fluoro-hexahydro-sila-difenidol: the first M\(_{2\beta}\)-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-63872 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 - Becker, B. T1 - Synthese und Eigenschaften von (Hydroxymethyl)dimethylgerman und (Hydroxymethyl)diphenylgerman N2 - Die (Hydroxymethyl)diorganylgermane (CH\(_3\))\(_2\)Ge(H)CH\(_2\)OH und (C\(_6\)H\(_5\))\(_2\)Ge(H)CH\(_2\)OH wurden - ausgehend von GeCl\(_4\) - durch eine jeweils vierstufige Synthese mit einer Gesamtausbeute von 15 bzw. 32% dargestellt (GeCl\(_4\) ---+ Cl\(_3\)GeCH\(_2\)Cl -> R \(_2\)Ge(Cl)CH \(_2\)Cl ->R \(_2\)Ge(OAc)CH\(_2\)OAc--) R \(_2\)Ge(H)CH\(_2\)OH; R = CH\(_3\) bzw. C\(_6\)H\(_5\) ). Die chemische Reaktivität der Germane (CH\(_3\))\(_2\)Ge(H)CH\(_2\)OH und (C\(_6\)H\(_5\))\(_2\)Ge(H)CH\(_2\)OH wird durch deren Ge-H- und 0-H-Bindung bestimmt. N2 - Starting from GeCl\(_4\) , the (hydroxymethyl)diorganylgermanes (CH\(_3\)) \(_2\)Ge(H)CH\(_2\)- 0H and (C\(_6\)H\(_5\)) \(_2\)Ge(H)CH\(_2\)OH were prepared by a four-step synthesis in total yields of 15 and 32%, respectively (GeCl\(_4\) ---. Cl\(_3\)GeCH\(_2\)Cl -> R \(_2\)Ge(Cl)CH\(_2\)Cl -> R \(_2\)Ge(OAc)CH\(_2\)OAc--+ R \(_2\)Ge(H)CH\(_2\)OH; R = CH\(_3\) or C\(_6\)H\(_5\) ). The chemical reactivity of (CH\(_3\) ) \(_2\)Ge(H)CH\(_2\)OH and (C\(_6\)H\(_5\)) \(_2\)Ge(H)CH \(_2\)OH was found to be determined by their Ge-Hand 0-H bonds. KW - Anorganische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63895 ER - TY - JOUR A1 - Syldatk, C. A1 - Stoffregen, A. A1 - Wuttke, F. A1 - Tacke, Reinhold T1 - Enantioselective reduction of acetyldimethylphenylsilane: a screening with thirty strains of microorganisms N2 - Thirty strains of microorganisms (bacteria, yeasts, fungi and green algae) were tested as resting free cells for their ability to transform acetyldimethylphenylsilane (1) enantioselectively into (R)-(1-hydroxyethyl) dimethylphenylsilane [(R)-2]. The biotransformations were monitared by GC (packed OV-17 column), and the enantiomeric purities of the products isolated were determined by HPLC (cellulose triacetate column, UV detection). All microorganisms tested were found to reduce 1 enantioselectively to give (R)-2. Under the test conditions used, the yeast Trigonapsis variabilis (DSM 70714) was found to 1 exhibif the highest specific activity (1.5 mg product x g cell wet mass\(^{-1}\) x min\(^{-1}\) ), whereas the highest enantioselectivities were observed for the bacteria Acinetobacter ca lcoaceticus (ATCC 31012) (>95% ee), Brevfbacterium species (ATCC 21860) (90% ee) and Corynebacterium dioxydans (ATCC 21766) (>95% ee), the yeast Candida humico la (OSM 70067) (90% ee), the fungus Cunninghame lla e legans (ATCC 26269) (94% ee), as well as the cyanobacterium Synechococcus leopoliensis (94% ee).· From the green algae tested, Chlamydomonas reinhardii showed the highest.enantioselectivity (85% ee). KW - Anorganische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63906 ER - TY - JOUR A1 - Eltze, M. A1 - Gmelin, G. A1 - Wess, J. A1 - Strohmann, C. A1 - Tacke, Reinhold A1 - Mutschler, E. A1 - Lambrecht, G. T1 - Presynaptic muscarinic receptors mediating inhibition of neurogenic contractions in rabbit vas deferens are of the ganglionic M\(_1\)-type N2 - The present study was designed to further charaeterize the presynaptie musearlnie M\(_1\)-reeeptor responsible for the inhibition of neuragenie eontraetions in the isolated rabbit vas deferens. Eleetrically induced twiteh eontraetions of this preparation were inhibited by the M\(_1\)-agonist, MeN-A-343, and by some of its analogs: 4-ehloro-phenyl derivative> MeN-A-343 > trans-olefinie analog> cis-olefinie analog. The same rank order of potency was observed for these agonists to raise the blood pressure of pithed rats by stimulation of M\(_1\)-receptors in sympathetie ganglia. A highly signifieant eorrelation was found between the antimusearinie potencies of atropine, pirenzepine and a series of 9 antagonists strueturally related to the ganglionie M\(_{1\beta}\)-receptor selective compounds, hexocyclium and hexahydro-difenidol, to antagonize the MeN-A-343-indueed inhibition of twitch eontraetions in rabbit vas deferens or the musearine-indueed depolarization in rat isolated superior eerVieal ganglia. It is suggested that the presynaptie musearlnie receptor that mediates inhibition of neuragenie contraetions in rabbit vas deferens is of the ganglionic M\(_{1\beta}\)-type. KW - Anorganische Chemie KW - Musearlnie aeetyleholine receptor antagonists KW - McN-A-343 analogs KW - Musearlnie receptor subtypes KW - Vas deferens (rabbit) KW - Pithed rat KW - Ganglia (rat) KW - Musearlnie aeetyleholine receptor agonists Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63912 ER -