Synthesis and pharmacological evaluation of a new class of 2-oxo-8-azaspiro (4,5)decan-1-ones as analogues of the muscarinic agonist RS-86.

A new series of 8-substituted-2-oxo-8-azaspiro (4,5)decan-1-ones has been synthesized and compounds tested for their cholinergic properties in comparison with the muscarinic agonist RS-86. Preliminary in vitro and in vivo pharmacological data indicate that none of them is provided with significant cholinergic effects either at central or peripheral level. A possible explanation for the lack of activity is given on the basis of conformational studies.