It has previously been shown [i, 3] that bisquaternary salts of~-dialkylaminoalkyl 1, 3- diphenylcyclobutane-2, 4-dicarboxylates have pronounced curariform activity. From a large number of compounds of this type synthesized and examined, two of the most active, cyclobutonium (I) and anatruxonium (II)[4] were selected, and after extensive pharmacological and clinical studies these were accepted by the Pharmacological ...