Synthesis of zwitterionic 4-hydroxy-2(1H)-quinolinone derivatives

Zwitterionic 4-hydroxy-2(1H)-quinolinone derivatives were synthesized through a unique reaction of 4-hydroxy-2(1H)-quinolinone with p-benzoquinone and N-heterocyclic aromatics. The zwitterions possessed astropisomeric nature. A possible mechanism of the reaction was presented.