Homologues of benzilylcholine mustard

Seven homologues of the alkylating muscarinic antagonist benzilylcholine mustard (BCM) have been prepared. The rate of reaction of the aziridinium ion derivatives with water is largely independent of the structure, whereas the rate of reaction with the muscarinic receptor drops markedly when the N-alkyl group is larger than n-propyl. PrBCM is practically equiactive with BCM. Recovery from block caused by PrBCM was first-order with a half-time of 32 h at 37°.