Abstract: Compounds of formula (I): ##STR1## wherein Z.sup.1 and Z.sup.2 are the same or different and each represents a methylenedioxy substituent, or up to three methoxy substituents;R.sup.2 and R.sup.3 are the same or different and each is alkyl having 1-3 carbon atoms, prop-2-enyl or prop-2-ynyl;R.sup.4 and R.sup.5 are the same or different and each is a benzyl or phenethyl group wherein the phenyl ring is optionally substituted by one or more of halogen, alkoxy having 1 to 3 carbon atoms and methylenedioxy;A and B are the same or different and each is an alkylene radical containing 1,2, or 3 carbon atoms;L is an alkylene chain having from 2 to 12 carbon atoms or is a group --L.sup.1.0.L.sup.2 -- wherein each of L.sup.1 and L.sup.2 is alkylene having at least two carbon atoms and taken together L.sup.1 and L.sup.2 having up to 11 carbon atoms; andX.sup.- is an anion;may be used to effect neuromuscular paralysis in mammals.