1-Methyl-4-(2-hydroxyethyl)-1,2,3,6-tetrahydropyridine and 1-methyl-4-acetyl-1,2,3,6-tetrahydropyridine (isoarecolone) methiodides and their reduced analogs have been prepared for study of the nicotinic acetylcholine receptor. Isoarecolone methiodide is a potent nicotinic agonist in the rectur abdominus muscle assay. Minimum energy conformations of these ligands were calculated by molecular modeling using a modified version of MM2 with ammonium parameters.