Abstract Several heterocyclic N-piperidine substituted salts were synthesized that were found to inhibit the specific binding of the antagonist [3 H] quinuclidinyl benzilate in radioligand muscarinic binding assays (3 H-QNB) in bioassays. One of the heterocyclic salts, compound 7, met the significance criteria in these assays (> 50% inhibition) at 10 μM of the nonselective muscarinic antagonist (3 H-QNB) in cells of the Wistar rat cerebral ...