Natural and synthetic xanthone derivatives are well known for their ability to act as antioxidants and/or enzyme inhibitors. This paper aims to present a successful synthetic methodology toward xanthenedione derivatives and the study of their aromatization to xanthones. Additionally their ability to reduce Fe(III), to scavenge DPPH radicals, and to inhibit AChE was evaluated. The results demonstrated that xanthenedione derivative 5e, bearing a catechol unit, showed higher reduction capacity than BHT and, similar to quercetin, strong DPPH scavenging activity (EC50 = 3.79 ± 0.06 µM) and it was also shown to be a potent AChEI (IC50 = 31.0 ± 0.09 µM) compared to galantamine (IC50 = 211.8 ± 9.5 µM).