title: Design and synthesis of methyl 2-methyl-7,7-dihalo-5-phenyl-2-azabicyclo[4.1.0]hept-3-ene-4-carboxylates with calcium channel antagonist activity.
abstract: A group of methyl 2-methyl-7,7-dihalo-5-(substituted-phenyl)-2-azabicyclo[4.1.0]hept-3-ene-4-carboxylates were prepared by reaction of dihalocarbenes (:CX2, X = Br, Cl) with methyl 1-methyl-4-(substituted-phenyl)-1,4-dihydropyridine-3-carboxylates. In vitro calcium channel antagonist activities were determined using a guinea pig ileum longitudinal smooth muscle assay. The title compounds exhibited weaker CC antagonist activity (10(-5)-10(-6)M range) than the reference drug nifedipine (1.4 x 10(-8)M). Structure-activity relationship studies showed that the position of a nitro substituent on the C-5 phenyl ring where the relative potency order was ortho > meta > para, and the size and/or electronegativity of the C-7 geminal-dihalo substituents (Br > Cl), were determinants of calcium channel antagonist activity. This class of compounds did not exhibit any inotropic effect on guinea pig left atria. A dihalocyclopropyl moiety is a potential bioisostere for the 2-methyl-3-methoxycarbonylvinyl moiety present in the calcium channel antagonist nifedipine.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2N8.
authors.forename: Javid S
authors.initials: JS
authors.lastname: Mojarrad
authors.forename: Ramin
authors.initials: R
authors.lastname: Miri
authors.forename: Edward E
authors.initials: EE
authors.lastname: Knaus
mesh_terms: D000818:Animals; D001372:Aza Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D002121:Calcium Channel Blockers / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D015220:Calcium Channels / Q000378:metabolism; D002264:Carboxylic Acids / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D015195:Drug Design; D006168:Guinea Pigs; D020128:Inhibitory Concentration 50; D008745:Methylation; D015394:Molecular Structure; D009130:Muscle, Smooth / Q000187:drug effects / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D001372:Aza Compounds; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D002264:Carboxylic Acids