Conformations and "nictinic" activites of cyclic analogues of choline aryl ether

The synthesis of cis and trans isomers of N,N-N-trimethyl-2-phenoxycyclohexylammonium bromide, cis-N,N,-N-trimethyl-2(2',6'-xylyloxy)cyclohexylammonium bromide, and N,N-dimethyl-3-phenoxypiperidinium bromide is described. Their structures and conformations were determined by NMR and uv absorption spectroscopy, the minimum torsional angles about the aryl-oxygen gond geing 20, 20, 80, and 27 degrees, respectively. Since the piperidinium compound stimulates ganglia, it is concluded the either planarity of the aryl--O--C system is not essential for this type of activity or receptor interaction can involve appreciable bond distortion. The absence of ganglion-stimulant activity in the remaining compounds indicates the need for a transoid arrangement of the O--C--C--N+ system.