title: Regioselective one-pot synthesis of 9-alkyl-6-chloropyrido[3,2-e][1,2,4]triazolo[4,3-a]pyrazines. Reactivity of aliphatic and aromatic hydrazides.
abstract: [reaction: see text] The one-pot synthesis of new 9-alkyl-6-chloropyrido[3,2-e][1,2,4]triazolo[4,3-a]pyrazines has been achieved. Hydrazides regioselectively reacted as nucleophiles with the 3-chloro substituent of 2,3-dichloropyrido[2,3-b]pyrazine. An intramolecular cyclization afforded the tricycle nonxanthine adenosine receptor antagonists.
authors.affiliation: Departamento de Química Farmacéutica y Orgánica, Facultad de Farmacia, Campus Cartuja s/n, 18071 Granada, Spain.
authors.forename: Asier
authors.initials: A
authors.lastname: Unciti-Broceta
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Pineda-de-las-Infantas
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Díaz-Mochón
authors.forename: Romeo
authors.initials: R
authors.lastname: Romagnoli
authors.forename: Pier G
authors.initials: PG
authors.lastname: Baraldi
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Gallo
authors.forename: Antonio
authors.initials: A
authors.lastname: Espinosa