Nuclear oxidation in the flavone series

Part VI. A new synthesis of calycopteretin and 6: 8-dihydroxy-quercetin
  • S. Rajagopalan
  • K. Visweswara Rao
  • T. R. Seshadri


It is shown that 5:6:7:8-hydroxy-flavonols (Calycopterein series) can be made from 5:6:7-hydroxy-flavonols (quercetagetin series) by the nuclear oxidation of the 8-position. Quercetagetin and nor-tangeretin have thus been converted into 6:8-dihydroxy-quercetin and calycopteretin in good yields.


Flavonol Nobiletin Dimethyl Sulphate Tangeretin Potassium Persulphate 
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Copyright information

© Indian Academy of Sciences 1947

Authors and Affiliations

  • S. Rajagopalan
    • 1
  • K. Visweswara Rao
    • 1
  • T. R. Seshadri
    • 1
  1. 1.Department of ChemistryAndhra UniversityWaltair

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