title: Cholinergic activity of acetylenic imidazoles and related compounds.
abstract: A series of acetylenic imidazoles related to oxotremorine (1a) were prepared and evaluated as cholinergic agents with in vitro binding assays and in vivo pharmacological tests in mice. 1-[4-(1H-Imidazol-1-yl)-2-butynyl]-2-pyrrolidinone (1b) was a cholinergic agonist with one-half the potency of oxotremorine. Analogues of 1b with a 5- or 2-methyl substituent in the imidazole ring (compounds 1c and 1g) were cholinergic partial agonists. Analogues of 1b with a methyl substituent at the 5-position in the pyrrolidinone ring (7b) or at the alpha-position in the acetylenic chain (8b) were antagonists. Various analogues of these imidazole acetylenes where the pyrrolidinone ring was replaced by an amide, carbamate, or urea residue were prepared. Several compounds which contained 5-methylimidazole as the amine substituent were partial agonists. The activities of the imidazole compounds are compared with those of the related pyrrolidine and dimethylamine analogues. Agonist and antagonist conformations for these compounds at muscarinic receptors are proposed.
authors.affiliation: Department of Medicinal Chemistry, Upjohn Company, Kalamazoo, Michigan 49001.
authors.forename: M W
authors.initials: MW
authors.lastname: Moon
authors.forename: C G
authors.initials: CG
authors.lastname: Chidester
authors.forename: R F
authors.initials: RF
authors.lastname: Heier
authors.forename: J K
authors.initials: JK
authors.lastname: Morris
authors.forename: R J
authors.initials: RJ
authors.lastname: Collins
authors.forename: R R
authors.initials: RR
authors.lastname: Russell
authors.forename: J W
authors.initials: JW
authors.lastname: Francis
authors.forename: G P
authors.initials: GP
authors.lastname: Sage
authors.forename: V H
authors.initials: VH
authors.lastname: Sethy
mesh_terms: D000114:Acetylene / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000378:metabolism; D007093:Imidazoles / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D015394:Molecular Structure; D018727:Muscarinic Antagonists; D010095:Oxotremorine / Q000031:analogs & derivatives* / Q000737:chemistry; D051381:Rats; D011976:Receptors, Muscarinic / Q000187:drug effects* / Q000502:physiology; D012472:Salivation / Q000187:drug effects; D013329:Structure-Activity Relationship; D013666:Tears / Q000187:drug effects / Q000378:metabolism; D014202:Tremor / Q000139:chemically induced; D014961:X-Ray Diffraction
chemical_list: D007093:Imidazoles; D018727:Muscarinic Antagonists; D011976:Receptors, Muscarinic; D010095:Oxotremorine; D000114:Acetylene