Antioxidant behaviour of 2′‐hydroxy‐chalcones: a study of their electrochemical properties

Abstract

The electrochemical behaviour of 13 chalcone analogues was systematically studied by means of cyclic voltammetry and chronoamperometry at a glassy carbon (GC), gold and platinum working electrodes using two different supporting electrolyte/solvent combinations. It was found that chalcone analogues can be easily oxidized at both GC and gold working electrodes, but not at a platinum electrode. Principal component analysis was further employed to reveal similarities/dissimilarities between oxidation potentials, chronoamperometric signals and ability of the compounds to scavenge the reactive oxygen species H 2 O 2 . The study reveals the inverse proportional relationship between the scavenging ability of H 2 O 2 , expressed as IC 50 , and chronoamperometric signal at 800 mV using gold as working electrode.

Studies on the Laccase‐Catalyzed Oxidation of 4‐Hydroxy‐Chalcones

“…The first stereoisomer (2R,3R)-3 a was eluted with a retention time of 36.8 min, the second one, (2S,3S)-3 b, at 44.6 min, and the third stereoisomer 3 c with a retention time of 49.2 min. 1 H NMR, 13 C NMR of (2R,3R)-3 a and (2S,3S)-3 b were identical to the above reported data for C. 1…”

“…The organic phase was dried (Na 2 SO 4 ), the solvent evaporated and the crude residue by silica gel flash chromatography to yield the chalcones 2 a-2 d. ). 13 [18] 13 [19] 13 [18] [18] UPDATES asc.wiley-vch.de…”

“…In this way, two stereoisomers could be isolated: compound C and compound D (see Figure 9.1 in Supplementary Materials). 13 13…”

“…The separation of the dimeric products was carried out by preparative scale HPLC using the chiral column and an isocratic elution (mobile phase: water/acetonitrile, 45:55; flow rate 5 mL min À 1 , detection at 400 nm). The first stereoisomer (2R,3R 13 13…”

“…Despite the fact that chalcones and specifically hydroxyl-chalcones are well-known antioxidants, [12,13] to our surprise there are only very few reports specifically devoted to the study of the outcome of oxidation reactions of these compounds [14] and, to the best of our knowledge, none of them describes the oxidation of 4-hydroxy chalcones (like our substrates 1 a-1 c and 2 a-2 d).…”