title: Microwave-assisted solvent-free synthesis and in vitro antibacterial screening of quinoxalines and pyrido[2, 3b]pyrazines.
abstract: We report herein the microwave assisted synthesis, without solvents and catalysts, of 6-substituted quinoxalines and 7-substituted pyrido[2,3b]pyrazines. The compounds were obtained in good yields and short reaction times using the mentioned procedure and two new structures are reported. A complete ¹H- and ¹³C-NMR assignment was performed using 1D and 2D-NMR. Additionally, an in vitro screening was performed on Gram-positive and Gram-negative bacteria using amoxicillin as positive reference. Compounds bearing a pyridyl group tended to have higher antibacterial activity, but the best activity against Bacillus subtilis and Proteus mirabilis was observed with quinoxaline derivatives.
authors.affiliation: Department of Organic Chemistry, Escuela Nacional de Ciencias Biológicas del Instituto Politécnico Nacional, Prol. Carpio y Plan de Ayala, México 11340 D. F., Mexico.
authors.forename: J Jesús
authors.initials: JJ
authors.lastname: Morales-Castellanos
authors.forename: Karina
authors.initials: K
authors.lastname: Ramírez-Hernández
authors.forename: Nancy S
authors.initials: NS
authors.lastname: Gómez-Flores
authors.forename: Oscar R
authors.initials: OR
authors.lastname: Rodas-Suárez
authors.forename: Javier
authors.initials: J
authors.lastname: Peralta-Cruz
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D008872:Microwaves; D011719:Pyrazines / Q000737:chemistry* / Q000494:pharmacology; D011810:Quinoxalines / Q000737:chemistry* / Q000494:pharmacology; D012997:Solvents
chemical_list: D000900:Anti-Bacterial Agents; D011719:Pyrazines; D011810:Quinoxalines; D012997:Solvents