In order to examine the structure-activity relationship for cholinergic action, cis-1-methylpiperidine-4, 3-acetolactone methiodide (1a) was designed and synthesized. The reaction of 1-carbobenzoxy-4-piperidone (3) with diethyl phosphonoacetate gave ethyl 1-carbobenzoxy-⊿4, α-piperidine-4-acetate (5), which was isomerized to the endo-isomer (6). Compound 6 was converted to an unsaturated lactone (9). Hydrogenation of 9 followed by methylation gave 1a. The compound 1a showed no acetylcholine-like activity but did show a weak atropine-like antagonistic effect to acetylcholine.