TY - JOUR A1 - Feifel, R. A1 - Wagner-Röder, M. A1 - Strohmann, C. A1 - Tacke, Reinhold A1 - Waelbroeck, M. A1 - Christophe, J. A1 - Mutschler, E. A1 - Lambrecht, G. T1 - Stereoselective inhibition of muscarinic receptor subtypes by the enantiomers of hexahydro-difenidol and acetylenic analogues N2 - 1 Tbc affinities of the (R)- and (S)-enantiomers of hexahydro-difenidol (1) and its acetylenie analogues hexbutinol (2), hexbutinol methiodide (3) and p-fluoro-hexbutinol (4) (stereochemieal purity > 99.8%) for musearlnie receptors in rabbit vas deferens (M1), guinea-pig atria (M2) and guinea-pig ileum (M3) were measured by dose-ratio experiments. 2 The (R)-enantiomers consistently showed higher aßinities than the (S)-isomers. The stereosclectivity ratios [(R)/(S)] wcrc greatest with thc enantiomers of 1 (vas deferens: 550; ilcum: 191; atria: 17) and least with thosc ofthc p-Fluoro-analogue 4 (vas defercns: 34; ileum: 8.5; atria: 1.7). 3 The enantiomerie potency ratios for compounds 1-4 were highest in rabbit vas deferens, intermediate in guinea-pig ileum and much less in guinea-pig atria. Thus, these ratios may serve as a predietor of muscarinic receptor subtype identity. 4 (S)-p-Fluoro-hexbutinol [(S)-4] showed a novel receptor selectivity profile with preference for M\(_3\) receptors: M\(_3\) > M\(_2\) \(\geq\) M\(_1\)• 5 These results do not conform to Pfeiffer's rule that aetivity differences between enantiomers are greater with more potent compounds. KW - Anorganische Chemie Y1 - 1990 UR - https://opus.bibliothek.uni-wuerzburg.de/frontdoor/index/index/docId/5596 UR - https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-64002 ER -