Quantitative structure-activity relationships in a set of antimuscarinic agents.

Quantitative structure-activity relationships (QSAR) have been formulated for the interactions of a set of antimuscarinic agents. The antagonistic activity is found to be dependent on hydrophobic-lipophilic character and steric requirements of substituents R1 and R2 in structures of type R1R2N--CH2--CH2--+NR3R4R5. Moreover, it is shown that the incumbrance of R3, R4 and R5 groups and their polar effects on the onium ending greatly affect the antagonistic activity. A binding model which suggests new avenues for exploration is presented.