ChemInform Abstract: New Imidazo[1,2‐a]quinoxaline Derivatives: Synthesis and in vitro Activity Against Human Melanoma.

Abstract

Pyrazine derivatives R 0550New Imidazo[1,2-a]quinoxaline Derivatives: Synthesis and in vitro Activity Against Human Melanoma. -Imidazoquinoxaline analogues (XI) are synthesized via a bimolecular condensation of imidazole carboxylic acid (I), coupling of condensation product (II) with o-fluoroaniline (III), and subsequent substitution on the imidazole moiety by Suzuki cross-coupling under microwave assistance. The new strategy not only reduces the number of purification steps but also offers a new common route for the preparation of unsubstituted imidazoquinoxalines on the imidazole core starting from the unsubstituted carboxylic acid. It also permits the introduction of a substituent in the last steps of the procedure. The new analogues (XI) demonstrate high antitumor activities against human melanoma and can be considered as promising lead compounds. -(DELEUZE-MASQUEFA*, C.; MOARBESS, G.; KHIER, S.; DAVID, N.; GAYRAUD-PANIAGUA, S.; BRESSOLLE, F.; PINGUET, F.; BONNET, P.-A.; Eur.

Scope of Tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the Synthesis of Triazoloquinoxalines, Imidazoloquinoxalines, and Rhenium-complexes thereof

“…Imidazo [1,2-a]quinoxalines have been reported to possess anticancer and antitumor properties [27,28] and show activity as adenosine receptor antagonists [29] as well as PDE4 inhibitors [30]. The reaction of ring-fused tetrazoles to imidazole-fused products via denitrogenative annulation leading to 2 is, compared to the ever-present CuAAC, less known and was only shown with one example so far.…”