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Synthetic route for the preparation of arylchalcones from the reported arylflavones. (A) General synthetic pathway from arylflavones to arylchalcones via arylflavanone intermediates. Reagents and conditions: (i) Pd/C (10%) or Pd(OH)2/C (20%), H2 (1 atm), EtOAc, room temperature, 12 h; (ii) t-BuOK (4 equiv), DMSO, room temperature, 15 min. The percentages shown correspond to the isolated yields obtained for each reaction step: flavone → flavanone (i) and flavanone → chalcone (ii). (B) Structures of the synthesized arylchalcone derivatives (3a–3j). (*): Arylflavones were previously synthesized and reported.