A NADES, choline chloride/water, allows a high yielding preparation of pure quinoxalines embedding acid sensitive and other functional groups at room temperature in very short reaction time.

1. Conditions favouring the condensation of o-phenylenediamine with alpha-oxo acids to form substituted quinoxalines have been investigated. The best yields (85-100%) are obtained by incubation of the reagents in 2m-hydrochloric acid. Substitution of acetic acid for hydrochloric acid, or of halogen-substituted 1,2-diaminobenzenes for phenylenediamine, increases the initial rate of reaction, but...

4,5-Dihydropyrrolo [1,2-a]quinoxalines are interesting druggable scaffolds, with multifaceted biological properties, including anticancer properties targeting the G protein-coupled estrogen receptor 1 (GPER). In this work, synthesis and preliminary antiproliferative activity of a small set new 4,5-dihydropyrrolo[1,2-a]quinoxalines (18-20) pyrrolo[1,2-a]quinoxalines (21, 22) has been reported, i...

Of the utmost importance of chirality in organic compounds and drugs, present work reports structure-chirality relationship three steroidal quinoxalines, which were synthesised by condensing diaminobenzenes with cholestenone. All purified characterised varying analytical tools prior to their chiroptical analysis circular dichroism (CD) technique. The substituent groups on quinoxalines contribut...

A novel strategy for an unconventional Pictet-Spengler reaction has been developed for the regioselective cyclization of the imidazole ring system at the C2 position. The developed strategy was utilized to develop a diversity-oriented parallel synthesis for bis(heterocyclic) skeletal novel analogs of benzimidazole-linked imidazoquinoxalines on a soluble polymer support under microwave condition...

The application of titanium dioxide as an oxidant in tandem oxidation type processes is described. Under microwave irradiation, quinoxalines have been synthesized in good yields from the corresponding alpha-hydroxyketones.

The rotary evaporation of 1,2-diamino aromatic compounds in diethyl oxalate at 50-80 °C and 20 mbar leads to the formation of quinoxalines-2,3-diones, as precipitates. Further purification is not necessary except for washing with ether.

N-glycosides of 6H-indolo[2,3-b]quinoxalines were prepared and structurally characterized. The synthesis relies on the cyclocondensation of isatine-N-glycosides with 1,2-diaminobenzenes. Some products exhibit weak cytotoxic activity against human ceratinocytes (HaCaT).

A series of tunable and regenerable biomimetic hydrogen sources, 4,5-dihydropyrrolo[1,2-a]quinoxalines, have been synthesized and applied in biomimetic asymmetric hydrogenation of 3-aryl-2H-benzo[b][1,4]oxazines and 1-alkyl-3-aryl-quinoxalin-2(1H)-ones, providing the chiral amines with up to 92% and 89% ee, respectively.

The syntheses of quinoxalines derived from 1,2-diamine and 1,2-dicarbonyl compounds under mild reaction conditions was carried out using a nanoparticle-supported cobalt catalyst. The supported nanocatalyst exhibited excellent activity and stability and it could be reused for at least ten times without any loss of activity. No cobalt contamination could be detected in the products by AAS measure...