Pentatomic cyclic agonists and muscarinic receptors: a 20 years review

The results of 20 years of structure-activity relationship (SAR) studies of pentatomic cyclic agonists on muscarinic receptors are reported and commented. Our results are compared with the findings obtained from quantitative structure-activity relationship (QSAR) studies and from those of molecular biology. The results from all three approaches point in the same direction and should help in the future design of new muscarinic agonists.