New Route to N-Aryl and N-Heteroaryl Derivatives of 4-Hydroxy-3-quinolinecarboxamides
The synthesis of N-aryl and N-heteroaryl substituted 4-hydroxy-3-quinolinecarboxamides 1 is described.The attack of dianions 12 of N-aryl substituted acetamides on the C-4 carbonyl of 4H-3,1-benzoxazin-4-ones 11 gave rise to ketoamides 13, which smoothly cyclized in the presence of bases to afford quinolinecarboxamides 1.By this method, a large number of 2-substituted 4-hydroxyquinolinecarboxamides can be prepared.