biostudies-literatureGruber NConsejo Nacional de Investigaciones Científicas y TécnicasUniversidad de Buenos Aires27391-27402https://www.ebi.ac.uk/biostudies/studies/S-EPMC10498151biostudies-literatureUnknown13(39)We present herein an in-depth study on the activity of amidinoquinoxaline <i>N</i>-oxides 1 against Gram-positive and Gram-negative anaerobic bacteria. Based on 5-phenyl-2,3-dihydropyrimidoquinoxaline <i>N</i>-oxide 1a, the selected structural variations included in our study comprise the substituents <i>α</i>- to the <i>N</i>-oxide function, the benzofused ring, substitution and quaternization of the amidine moiety, and the amidine ring size. Compounds 1 showed good to excellent antianaerobic activity, evaluated as the corresponding CIM₅₀ and CIM₉₀ values, and an antimicrobial spectrum similar to metronidazole. Six out of 13 compounds 1 had CIM₉₀ values significantly lower than the reference drug. Among them, imidazoline derivatives 1i-l were the most actiRSC advancesAmidinoquinoxaline <i>N</i>-oxides: synthesis and activity against anaerobic bacteria.PMC1049815111220200101694CO20020170100189BAGonzalez Maglio DHPaz MLFernandez-Canigia LGarcia MBGruber NOrelli LRStipa PBisceglia JAKilimciler NBfalseAmidinoquinoxaline <i>N</i>-oxides: synthesis and activity against anaerobic bacteria.We present herein an in-depth study on the activity of amidinoquinoxaline <i>N</i>-oxides 1 against Gram-positive and Gram-negative anaerobic bacteria. Based on 5-phenyl-2,3-dihydropyrimidoquinoxaline <i>N</i>-oxide 1a, the selected structural variations included in our study comprise the substituents <i>α</i>- to the <i>N</i>-oxide function, the benzofused ring, substitution and quaternization of the amidine moiety, and the amidine ring size. Compounds 1 showed good to excellent antianaerobic activity, evaluated as the corresponding CIM₅₀ and CIM₉₀ values, and an antimicrobial spectrum similar to metronidazole. Six out of 13 compounds 1 had CIM₉₀ values significantly lower than the reference drug. Among them, imidazoline derivatives 1i-l were the most acti2023-01-01T00:00:00Z2023 Sep2026-06-04T09:35:16.067Z2024-11-13T01:22:09.172ZS-EPMC104981513771138110.1039/d3ra01184d