Quinoxaline antibiotics are chromopeptide lactones embracing the two families of triostins and quinomycins, each having characteristic sulfur-containing cross-bridges. Interest in these compounds stems from their antineoplastic activities and their specific binding to DNA via bifunctional intercalation of the twin chromophores represented by quinoxaline-2-carboxylic acid (QA). Enzymatic analysi...

A new brush-type HPLC chiral stationary phase (CSP) comprising π-acidic N-(3,5-dinitrobenzoyl)-D-α-phenylglycine chiral units bound to the quinoxaline units of modified γ-aminopropyl silica gel by a 1,2-diaminoethane spacer has been prepared by solid-phase synthesis. To test the CSP attempts were made to separate the enantiomers of twenty-two racemates with different functional groups and the r...

Phospho sulfonic acid (PSA) synthesized as an environmentally safe and efficient solid acid catalyst, and it used for the synthesis of several 2-disubstituted benzimidazoles, 2-substituted benzoxazoles, and 2-substituted quinoxalines in ethanol as a green solvent at ambient temperature is described. (i) A very simple, green and efficient procedure for the synthesis of benzimidazole and also benz...

In the mol-ecule of the title compound, C(12)H(12)N(2)O, the quinoxaline ring is planar with an r.m.s. deviation of 0.007 (15) Å. The dihedral angle between the quinoxaline and propenyl planes is 82.1 (2)°. The crystal packing is stabilized by offset π-π stacking between the quinoxaline rings [centroid-centroid distance = 3.8832 (9) Å].

9,10-Quinoxaline-fused porphycenes 1a-H₂ and 1b-H₂ were synthesized by intramolecular McMurry coupling. As a result of the annulation of the quinoxaline moiety on the porphycene skeleton, 1a-H₂ and 1b-H₂ display absorption and fluorescence in the near infra-red (NIR) region. Additionally, the quinoxaline moieties of 1a-H₂ and 1b-H₂ act as electron-withdrawing groups, introducing lower reduction...