One-Pot Synthesis of New 2,3-Disubstituted Thiazolo[4,5-b]quinoxalines through Pd-Catalyzed Coupling Reaction/Hetero-Annulation

The Sonogashira cross-coupling reaction of terminal acetylenes with aryl or vinyl halides has been evidenced to be a powerful method for the creation of substituted alkynes, which has been widely applied in the synthesis of heterocyclic compounds [1]. The thiazoloquinoxaline ring system dramatically increases a variety of biological properties such as the anti-bacterial, anti-viral, and anti-amoebic activities [2-3].In this work, we synthesized a number of 3- benzyl-2-(4-styryl)-2,3-dihydrothiazolo[4,5-b]quinoxaline3 derivatives from the Sonogashira coupling reaction of 2-chloro-3-(prop-2-ynylthio)quinoxaline 1 with various aryl iodides followed by hydroamination and the subsequent cyclization of the resulting 2-chloro-3-((3-(4- nitrophenyl)prop-2-yn-1-yl)thio) quinoxaline2in a One-Pot procedure. Theproducts obtained were characterized by the spectroscopic data and screened for anti-bacterial activity.