title: Synthesis and antibacterial properties of new N4-acetylated hexahydro-2,7-dioxopyrido[2,3-f]quinoxaline-8-carboxylic acids.
abstract: Direct interaction between 7-chloro-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid and primary α-amino acids (exemplified by glycine, alanine, and l-valine) in aqueous ethanolic NaHCO(3) at 70-80°C for 24-72 h produced the respective N-(4-oxoquinolin-7-yl)-α-amino acids (6a-c). The latter derivatives underwent reductive lactamization upon treatment with Na(2)S(2)O(4) in aqueous ethanol to afford moderate yields of the corresponding pyrido[2,3-f]quinoxaline-8-carboxylic acids (8a-c). Acetylation of 8a-c using acetyl chloride afforded N(4)-acetylated hexahydro-2,7-dioxopyrido[2,3-f]quinoxaline-8-carboxylic acids (9a-c). The structures, assigned to these new heterocyclic products, are supported by analytical and spectral data. The synthesized compounds (6a-c/9a-c) showed appreciable antibacterial activity as compared with ciprofloxacin.
authors.affiliation: Department of Pharmacy, University of Jordan, Amman, Jordan.
authors.forename: Yusuf M
authors.initials: YM
authors.lastname: Al-Hiari
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Shakya
authors.forename: Muhammed H
authors.initials: MH
authors.lastname: Alzweiri
authors.forename: Tariq M
authors.initials: TM
authors.lastname: Al-Qirim
authors.forename: Ghassan
authors.initials: G
authors.lastname: Shattat
authors.forename: Mustafa M
authors.initials: MM
authors.lastname: El-Abadelah
mesh_terms: D000107:Acetylation; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D002264:Carboxylic Acids / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D011804:Quinolines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D002264:Carboxylic Acids; D011804:Quinolines