Various novel polycyclic thiopyranoindol annulated [3,4-c]quinolone derivatives were synthesized via domino Knoevenagel-hetero-Diels–Alder reactions of indoline-2-thions and novel N-acrylated anthranilaldehydes in refluxing ethanol as a solvent in the presence of 20 mol% ZnBr₂ as a Lewis acid catalyst. All reactions proceed with high yields with excellent regio- and stereoselectivity.

中文翻译：

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ZnBr2催化多米诺Knoevenagel-杂-Diels-Alder反应：一种有效的途径来制备多环硫代吡喃并吲哚环化的[3,4-c]喹诺酮衍生物

在20 mol的乙醇存在下，通过吲哚-2-噻吩的多米诺酮的Knoevenagel-杂Diels-Alder反应和新颖的N-丙烯酸蒽醛在回流的乙醇中作为溶剂合成了各种新的多环硫吡喃吲哚环化的[3,4-c]喹诺酮衍生物。 ％ZnBr ₂作为路易斯酸催化剂。所有反应均以高产率进行，具有优异的区域选择性和立体选择性。