Synthesis and pharmacology of nicotinyl-choline and three bisquaternary related derivatives

Abstract

Nieotinylcholine and three related bisquaternary derivatives, nicotinylcholine iodide methiodide, nicotinylhomocholine iodide methiodide and pyridyl-3-acetycholine iodide methiodide, have been synthesized and studied pharmacologically. Nictinylcholine is in general less potent than naturally-occurring choline esters. It is practically devoid of muscarinic actions, but in cats in doses of 5–10 mg/kg body weight it possesses pronounced nicotinic actions (ganglion-stimulating and neuromuscular-blocking actions). It is split by butyrocholinesterase at approximately the same rate as acetylcholine. On the frog recrus nicotinylcholine is about 300 times less potent than acetylcholine. The corresponding bisquaternary compound, nicotinylcholine iodide methiodide, is not split by cholinesterases, and in doses of 10–20 mg/kg body weight it possesses ganglion-blocking properties. It has no effect on neuromuscular transmission as revealed by the cat sciatic nerve-gastrocnemius preparation. The other two bisquaternary compounds, nicotinylhomocholine iodide methiodide and pyridyl 3-acetylcholine iodide methiodide, have neuromuscular blocking actions in doses of 5–10 mg/kg body weight, but have little effect on the cat blood pressure. They are not split by cholinesterases.