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Updated: Aug 12, 2026

Subcutaneous Administration of Muscarinic Antagonists and Triple-Immunostaining of the Levator Auris Longus Muscle in Mice
Published on: September 8, 2011
Synthesis and structure-activity relationships of new muscarinic antagonists
V I Cohen1, R E Gibson, R C Reba
1Section of Radiopharmaceutical Chemistry, George Washington University Medical Center, Washington, DC 20037.
Abstract:
In an attempt to develop more selective muscarinic acetylcholine receptor (m-AcChR) antagonists, (R)-1-azabicyclo[2.2.2]oct-3-yl-thioxanthene-9-carboxylate, (R,S)-thiochromane-4-carboxylate, and (R,S)-chromane-4-carboxylate were synthesized. Evaluation of the binding affinities of these compounds to muscarinic receptors indicates that replacing the oxygen by sulfur in the xanthenyl and chromanyl moieties does not significantly change selectivity, but does reduce the affinity of 5 and enhance the affinity of 9a.
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