QSAR in a series of muscarinic agents. Note V. New sets of rigid and flexible ligands.

A deeper insight of muscarinic receptor attachment points is obtained on studying new sets of rigid and flexible ligands. The quantitative analysis of the correspondence between biological response and structural ligand features confirms that pD2 values are strongly dependent on hydrophobic and steric parameters. Moreover, it is shown that receptor attachment points are interrelated and their simultaneous perturbations contribute to enhance the activity with comparable effectiveness.