Synthesis and antioxidant properties of new chromone derivatives.
Nowadays, the recognition of the benefits of antioxidants is eliciting an increasingly interest in the search for new molecules with improved activity. The aim of the present work was to search for improved reactive oxygen species (ROS) and reactive nitrogen species (RNS) scavengers by testing new structures of 2-styrylchromones (2-SC) and 3-substituted flavones, which were synthesised by the Baker-Venkataraman approach. The new compounds were also tested for their metal chelating capacity and reducing activity. The obtained results showed that the methylation of hydroxyl groups decreases the scavenging of ROS and RNS by 2-SC. The decrease in the scavenging activities was, generally, more evident when the methylation occurred in B-ring, except for O2*- and (1)O(2). On the other hand, the introduction of a substituent, either hydroxyl or methoxyl, in position 8 was sometimes favourable and others unfavourable to the scavenging activities, depending on the reactive species. In conclusion, the study of the antioxidant properties of the new 2-SC and flavones allowed establishing new structure-activity relationships and brought out, in some cases, pharmacophores with improved activity.
Gomes
Ana
A
REQUIMTE, Departamento de Química-Física, Faculdade de Farmácia, Universidade do Porto, Rua Aníbal Cunha, 164, 4099-030 Porto, Portugal.
Neuwirth
Ondrej
O
Freitas
Marisa
M
Couto
Diana
D
Ribeiro
Daniela
D
Figueiredo
Andrea G P R
AG
Silva
Artur M S
AM
Seixas
Raquel S G R
RS
Pinto
Diana C G A
DC
Tomé
Augusto C
AC
Cavaleiro
José A S
JA
Fernandes
Eduarda
E
Lima
José L F C
JL
D000975:Antioxidants / Q000138:chemical synthesis* / Q000494:pharmacology*; D002867:Chromones / Q000138:chemical synthesis* / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008745:Methylation; D026361:Reactive Nitrogen Species / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
D000975:Antioxidants; D002867:Chromones; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species