title: Synthesis of 6-methyl-3,4-dihydropyrazinones using an Ugi 4-CR/allenamide cycloisomerization protocol.
abstract: A synthetic approach to the 6-methyl-3,4-dihydropyrazinone core from Ugi adducts is described. This methodology relies on the regioselective C-N bond formation between an allenamide moiety at C-β and an amide anion formed under base-mediated conditions. This protocol allows easy access to tricyclic systems such as pyrazino[2,1-a]isoindole and pyrazino[2,1-a]isoquinoline nuclei.
authors.affiliation: Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, México, D.F., México. lpolindara@iquimica.unam.mx lmiranda@unam.mx.
authors.forename: Estefanía
authors.initials: E
authors.lastname: Icelo-Ávila
authors.affiliation: Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, México, D.F., México. lpolindara@iquimica.unam.mx lmiranda@unam.mx.
authors.forename: Yoarhy A
authors.initials: YA
authors.lastname: Amador-Sánchez
authors.affiliation: Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, México, D.F., México. lpolindara@iquimica.unam.mx lmiranda@unam.mx.
authors.forename: Luis A
authors.identifier: http://orcid.org/0000-0003-3066-2104
authors.initials: LA
authors.lastname: Polindara-García
authors.affiliation: Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, México, D.F., México. lpolindara@iquimica.unam.mx lmiranda@unam.mx.
authors.forename: Luis D
authors.initials: LD
authors.lastname: Miranda