Stereoselectivity of oxotremorine antagonists containing a chiral pyrrolidine group

Oxotremorine (Ia) and its succinimide analogue (IIa) have been substituted in the pyrrolidine ring with a methyl group in the 2- or 3-positions. The compounds are oxotremorine antagonists. The 2-methyl-substituted enantiomers show stereoselectivity, the S-isomers being the most active.