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Published on: June 10, 2021
A new synthetic approach to functionalize pyrimido[4,5-b]quinoline-2,4(1H,3H)-diones via a three-component one-pot
Karen Aknin1, Stéphanie Desbène-Finck, Philippe Helissey
1Laboratoire de Chimie Thérapeutique, UMR CNRS N 8638, Université Paris Descartes, Faculté des Sciences, Pharmaceutiques et Biologiques, 4 avenue de l'Observatoire, 75270, Paris Cedex 06, France.
Abstract:
Functionalized pyrimido[4,5-b]quinoline-2,4 (1H,3H)-diones were synthesized by a three-component one-pot reaction involving barbituric acid, aldehydes, and anilines. The use of commercially available anilines allowed the facile syntheses of pyrimido[4,5-b]quinolinediones substituted in all the positions on the benzene ring with electron donor or electron withdrawing groups. This straightforward method circumvents the preparation of unstable substituted 2-aminobenzaldehydes that limits the scope of previously described syntheses. Furthermore, access to the 5-substituted derivatives is now also possible starting from aliphatic or aromatic aldehydes. Our strategy and methodology offer significant and practical improvements over other methodologies.
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