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  - Bentlage, Anke
A1  - Towart, Robertson
A1  - Möller, Eike
T1  - Sila-pharmaca, XXV. Sila-analogues of nifedipine-like dialkyl 2,6-dimethyl-4-aryl-1,4 dihydropyridine-3,5-dicarboxylates, III
N2  - 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-Dünnschichtchromatographie wurde gezeigt, daß die Sila- bzw. Disila-Analoga lipophiler sind als die entsprechenden C-Verbindungen. Bezüglich der spasmolytischen in vitra-Aktivitäten zeigen die Si-Verbindungen in erster Näherung ähnliche Struktur-Wirkungs-Beziehungen wie ihre Carba-Analoga. Dagegen konnten hinsichtlich der ill vlva-Effekte (cardiovasculäre und antihypertensive Aktivität) in einigen Fällen große Unterschiede nachgewiesen werden.
N2  - 15 new C/Si-analogue pairs (C-compounds and sila- or disila-substituted derivatives, respectively), which are structurally related to nifedipine, have been synthesized. These and some further C/Si-pairs have been investigated comparatively with respect to their physicochemical and pharmacological properties. Using reversed-phase thin-layer chromatography it was shown that both the sila- and disila-analogues are more Iipophilic than the corresponding C-compounds. With respect to the in vitra spasmolytic potencies the Si-compounds show approximately similar structure-activity relationships to their carba-analogues. However, in some cases marked differences in in vivo effects (cardiovascular and antihypertensive activity) could be demonstrated.
KW  - Anorganische Chemie
Y1  - 1983
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78357
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Wuttke, F.
A1  - Henke, H.
T1  - Zur Stereochemie der mikrobiellen Reduktion von rac-Acetyl( t-butyl)methylphenylsilan mit Trigonopsis variabilis (DSM 70714) und Corynebacterium dioxydans (ATCC 21766): Aufklärung der absoluten Konfiguration der Biotransformationsprodukte (SiR,CR)- und ( SiS ,CR)-t-Butyl( 1-hydroxyethyl)methylphenylsilan
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64176
ER  - 
TY  - JOUR
A1  - Braunschweig, Holger
A1  - Damme, Alexander
T1  - 1,2-Bis(dimethylamino)-1,2-bis(2,4,6-triisopropylphenyl)diborane(4)
N2  - In the molecular structure of the title compound, C34H58B2N2, each B atom of the diborane(4) is connected to one dimethylamino group and one Tip ligand (Tip = 2,4,6-triisopropylphenyl). These findings indicate that the increased steric demand of the Tip groups exerts influence solely on the B—B separation but not on the overall geometry of the title compound.
KW  - Anorganische Chemie
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-67639
ER  - 
TY  - JOUR
A1  - Braunschweig, Holger
A1  - Dewhurst, Rian D.
A1  - Schwab, Katrin
A1  - Wagner, Katharina
T1  - {N ',N ''-Bis[2,6-bis(1-methylethyl)phenyl]-N,N-dimethylguanidinato-kappa N-2 ',N ''}dibromidoborane
N2  - In the molecular structure of the title compound, C27H40N3BBr2, the B atom is connected to two bromide substituents and a guanidinate scaffold, forming a four– membered ring. An aryl group is connected to each N atom in the ring that contains two isopropyl groups in positions 2 and 6.
KW  - Anorganische Chemie
Y1  - 2010
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-67622
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mühleisen, M.
T1  - 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
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64400
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  - Tacke, Reinhold
A1  - Mühleisen, M.
T1  - Hexacoordinate silicon in a compound with an F\(_5\)SiC unit
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64378
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  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Lopez-Mras, A.
A1  - Jones, P. G.
T1  - 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
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64339
ER  - 
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  - 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  - Wagner, S. A.
A1  - Brakmann, S.
A1  - Wuttke, F.
A1  - Eilert, U.
A1  - Fischer, L.
A1  - Syldatk, C.
T1  - 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.
N2  - 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.
KW  - Anorganische Chemie
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64299
ER  - 
TY  - JOUR
A1  - Eltze, M.
A1  - Ullrich, B.
A1  - Mutschler, E.
A1  - Moser, U.
A1  - Bungardt, E.
A1  - Friebe, T.
A1  - Gubitz, C.
A1  - Tacke, Reinhold
A1  - Lambrecht, G.
T1  - Characterization of muscarinic receptors mediating vasodilation in rat perfused kidney
N2  - 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.
KW  - Anorganische Chemie
KW  - Kidney (perfused
KW  - rat)
KW  - Muscarinic receptor agonists
KW  - Muscarinic receptor antagonists
KW  - Arterioles (submucosal)
KW  - Ileum; Atrium
KW  - Vas deferens
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64283
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Becht, J.
A1  - Lopez-Mras, A.
A1  - Sheldrick, W. S.
A1  - Sebald, A.
T1  - Syntheses, X-ray crystal structure analyses, and solid-state NMR studies of some zwitterionic organofluorosilicates
N2  - No abstract available
KW  - Anorganische Chemie
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64272
ER  - 
TY  - JOUR
A1  - Waelbroeck, M.
A1  - Camus, J.
A1  - Tastenoy, M.
A1  - Mutschler, E.
A1  - Strohmann, C.
A1  - Tacke, Reinhold
A1  - Schjelderup, L.
A1  - Aasen, A.
A1  - Lambrecht, G.
A1  - Christophe, J.
T1  - Stereoselective interaction of procyclidine, hexahydro-difenidol, hexbutinol and oxyphencyclimine, and of related antagonists, with four muscarinic receptors
N2  - 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.
KW  - Anorganische Chemie
KW  - Muscarinic receptors
KW  - Hexahydro-difenidol
KW  - Oxyphencyclimine
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64237
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Becker, B.
A1  - Berg, D.
A1  - Brandes, W.
A1  - Dutzmann, S.
A1  - Schaller, S.
T1  - 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
N2  - 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 üpolytica and Pyricularia oryzae, the mode of action being primarily an inhtbition of oxidative C14-demethylation.
KW  - Anorganische Chemie
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64224
ER  - 
TY  - JOUR
A1  - Bungardt, E.
A1  - Vockert, E.
A1  - Feifel, R.
A1  - Moser, U.
A1  - Tacke, Reinhold
A1  - Mutschler, E.
A1  - Lambrecht, G.
A1  - Suprenant, A.
T1  - Characterization of muscarinic receptors mediating vasodilation in guinea-pig ileum submucosal arterioles by the use of computer-assisted videomicroscopy
N2  - 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.
KW  - Anorganische Chemie
KW  - Muscarinic receptor subtypes; Muscarinic rcceptor agonists (M 1-selective)
KW  - Muscarinic receptor antagonists (M 3-selective)
KW  - Vidcomicroscopy
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64206
ER  - 
TY  - JOUR
A1  - Tacke, Reinhold
A1  - Mahner, K.
A1  - Strohmann, C.
A1  - Forth, B.
A1  - Mutschler, E.
A1  - Friebe, T.
A1  - Lambrecht, G.
T1  - Cyclohexyl(4-fluorophenyl)(3-piperidinopropyl)silanol (p-fluoro-hexahydro-sila-difenidol, p-F-HHSiD) and derivatives: synthesis and antimuscarinic properties
N2  - 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.
KW  - Anorganische Chemie
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64162
ER  - 
TY  - JOUR
A1  - Hengelsberg, H.
A1  - Tacke, Reinhold
A1  - Fritsche, K.
A1  - Syldatk, C.
A1  - Wagner, F.
T1  - Synthesis and enantioselective enzymatic hydrolysis of rac-dimethylphenyl[1-(phenylacetamido)- ethyl]silane
N2  - 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.
KW  - Anorganische Chemie
Y1  - 1991
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64153
ER  -