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...

A new series of indolocarbazole-quinoxalines (ICQ, receptors 6 and 7) are prepared and characterized for effective fluoride and acetate anion sensing. The new indole-based system has a highly flat rigid structure with a large pi system, and exhibits high binding affinity and sensitivity for acetate and fluoride anions. Receptors 6 and 7 give abundant and unique spectral features in dimethyl sul...

The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Electrochemical and density functional studies demonstrate that coordination of electrolyte constituents to quinoxalines modulates their electrochemical properties. Quinoxalines are shown to be electrochemically inactive in most electrolytes in propylene carbonate, yet the pred...

A series of novel N-substituted indophenazine derivatives were synthesised and screened for antiviral activity against a panel of human pathogenic viruses. New compounds were synthesised through modifying the N-hydrogen of indophenazine moiety with different substitution and formaldehyde by Mannich reaction. The structure of the synthetic compounds was characterised by means of infra red and nu...

The high commercial demand for quinoxalines needs a rapid, greener and safer synthetic method among the chemists. A series of quinoxaline derivatives has been synthesized by condensation of diamines and dicarboniles in microwave heating conditions and in solvent free media. This environmentally benign synthetic approach gives us excellent yields (80-90%) in shorter reaction time (3.5 minutes.)....

TFA alone was found to be remarkably effective for the intramolecular hydroarylation (IMHA) of alkynes when employed as a solvent in the cyclization of 3-alkynyl substituted 2-(indol-3-yl)quinoxalines. This simple and metal free cyclization method afforded a range of indolophenazines as new and potential cytotoxic agents. The use of excess TFA was found to be crucial for the success of this rea...