title: New insights into the antioxidant activity of hydroxycinnamic acids: Synthesis and physicochemical characterization of novel halogenated derivatives.
abstract: An interdisciplinary research project was developed combining the synthesis of a series of hydroxycinnamic acid derivatives and the evaluation of their physicochemical parameters (namely redox potentials and partition coefficients), along with the corresponding antioxidant activity. A structure-property-activity relationship (SPAR) approach was then applied aiming at establishing a putative relation between the physicochemical parameters of the compounds under study and their antioxidant activity. The results gathered allow concluding that the redox potentials could contribute to the understanding of the antioxidant activity and that the presence of an electron withdrawing group (EWG) of halogen type, namely a bromo atom, in an ortho position to a phenolic group of the cinnamic scaffold does not influence the antioxidant activity. On the other hand after the introduction of this type of substituent a significant increase on the lipophilicity of cinnamic derivatives was observed, which is a feature of extreme importance in the development of novel lipophilic antioxidants. The SPAR results revealed a relation between the redox potentials and the antioxidant activity of hydroxycinnamic acids and derivatives. The data obtained operate as a positive reinforce of the tendency to use redox properties as a guideline of the rational design of this type of compounds.
authors.affiliation: UQFM/Departamento de Química Orgânica, Faculdade de Farmácia, Universidade do Porto, Rua Aníbal Cunha 164, 4050-030 Porto, Portugal.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Gaspar
authors.forename: E Manuela
authors.initials: EM
authors.lastname: Garrido
authors.forename: Mário
authors.initials: M
authors.lastname: Esteves
authors.forename: Elias
authors.initials: E
authors.lastname: Quezada
authors.forename: Nuno
authors.initials: N
authors.lastname: Milhazes
authors.forename: Jorge
authors.initials: J
authors.lastname: Garrido
authors.forename: Fernanda
authors.initials: F
authors.lastname: Borges
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis*; D003373:Coumaric Acids / Q000138:chemical synthesis* / Q000494:pharmacology; D054879:Halogenation; D006801:Humans; D010084:Oxidation-Reduction; D021281:Quantitative Structure-Activity Relationship
chemical_list: D000975:Antioxidants; D003373:Coumaric Acids