Molecules (Apr 2015)

A Trinuclear Oxo-Chromium(III) Complex Containing the Natural Flavonoid Primuletin: Synthesis, Characterization, and Antiradical Properties

  • Anamaria D. P. Alexiou,
  • Carla C. Decandio,
  • Sabrina da N. Almeida,
  • Marcelo J. P. Ferreira,
  • Paulete Romoff,
  • Reginaldo C. Rocha

DOI
https://doi.org/10.3390/molecules20046310
Journal volume & issue
Vol. 20, no. 4
pp. 6310 – 6318

Abstract

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A new trinuclear oxo-centered chromium(III) complex with formula [Cr3O(CH3CO2)6(L)(H2O)2] (L = 5-hydroxyflavone, known as primuletin) was synthetized and characterized by ESI mass spectrometry, thermogravimetry, and 1H-NMR, UV-Vis, and FTIR spectroscopies. In agreement with the experimental results, DFT calculations indicated that the flavonoid ligand is coordinated to one of the three Cr(III) centers in an O,O-bidentate mode through the 5-hydroxy/4-keto groups. In a comparative study involving the uncoordinated primuletin and its corresponding complex, systematic reactions with the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) showed that antiradical activity increases upon complexation.

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