title: Imidazo[1,5-a]pyrimidine and benzo[4,5]imidazo-[1,2-a]pyrimidine derivatives as calcium antagonists.
abstract: Several bicyclic dihydropyrimidines were synthesized and evaluated for their calcium antagonistic activities by comparison with the usual 1,4-dihydropyridine calcium antagonist reference compound nifedipine. The solid-state structure of the isopropyl 2-methyl-4-(3'-nitrophenyl)-1,4-dihydrobenzo[4,5]imidazo[1,2- a]pyrimido-3-carboxylate shows that these compounds can adopt the most important structural features of the 1,4-dihydropyridine and 1,4-dihydropyrimidine calcium channel blockers. The high-potassium depolarized rat aorta assay was used for testing the compounds as calcium channel blockers. Some compounds showed interesting vasorelaxant activity.
authors.affiliation: Departamento de Química Orgánica, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Alajarin
authors.forename: J J
authors.initials: JJ
authors.lastname: Vaquero
authors.forename: J
authors.initials: J
authors.lastname: Alvarez-Builla
authors.forename: M F
authors.initials: MF
authors.lastname: de Casa-Juana
authors.forename: C
authors.initials: C
authors.lastname: Sunkel
authors.forename: J G
authors.initials: JG
authors.lastname: Priego
authors.forename: P
authors.initials: P
authors.lastname: Gomez-Sal
authors.forename: R
authors.initials: R
authors.lastname: Torres
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004353:Drug Evaluation, Preclinical; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008958:Models, Molecular; D015394:Molecular Structure; D011743:Pyrimidines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014665:Vasodilator Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology
chemical_list: D002121:Calcium Channel Blockers; D011743:Pyrimidines; D014665:Vasodilator Agents