Paralysing Activity of some Further Heterocyclic Decamethylene-αω-bisQuaternary Ammonium Salts

Abstract

IN our recent communication on the synthesis and paralysing activity of a series of heterocyclic bisquaternary ammonium salts1, we directed attention to the fact that introduction of a methoxyl group into the nucleus increased the activity of the parent compounds. We have now synthesized further compounds of the type already described but containing more than one methoxyl group. We find that decamethylene-αω-bis 6.7-dimethoxy 1.2.3.4-tetra-hydroisoquinolinium methiodide (14) is more active than the corresponding 6-methoxy compound (12), and that the 6.7.8-trimethoxy compound (15) is still more active. Compound 15 abolishes the righting reflex of rabbits at an intravenous dose of 20 µgm. per kgm. We believe that in the rabbit this compound is the most active purely synthetic paralysing substance yet reported. It is about seven times as effective as decamethonium iodide in abolishing the righting reflex of this animal. It is worthy of note that compound 15 is antagonized by neostigmine.