A series of new derivatives, related to diphenidol and to its 2-carbonyl analogue, were designed as antimuscarinic agents. The synthesized compounds were evaluated both as hydrochlorides and as methiodides by functional tests at guinea-pig heart (M2), guinea-pig ileum (M3) and rabbit vas deferens (putative M4). Two derivatives (3a and 5a) showed an M3-selective profile similar to that of the reference compounds, though they resulted less ...
