title: In vitro antioxidant properties of potential biotransformation products of salicylate, sulphasalazine and amidopyrine.
abstract: 2,3-and 2,5-dihydroxybenzoate (formed from salicylate by nonenzymatic or enzymatic hydroxylation), and 5-aminosalicylate (a prime metabolite of sulphasalazine) are highly efficient quenchers of the chemiluminescence (CL) produced by an oxy radical flux. Monohydric phenols (including salicylate) and meta-dihydric phenols are virtually inactive. These findings suggest that the para- or ortho-configuration of hydroxy/amino groups is important for this activity. These differences in activity between 2,3- and 2,5-dihydroxybenzoate, 5-aminosalicylate and monohydric phenols/2,4-, 2,6-dihydroxybenzoate were not seen in assays monitoring hydroxyl radicals. 4-aminophenazone (an oxidation product of both amidopyrine/aminopyrine and isopyrine), 4-hydroxyphenazone and some dietary catechols (and ascorbate), are also quenchers of oxy radical-associated CL.
authors.forename: W H
authors.initials: WH
authors.lastname: Betts
authors.forename: M W
authors.initials: MW
authors.lastname: Whitehouse
authors.forename: L G
authors.initials: LG
authors.lastname: Cleland
authors.forename: B
authors.initials: B
authors.lastname: Vernon-Roberts
mesh_terms: D000632:Aminopyrine / Q000031:analogs & derivatives / Q000494:pharmacology; D000975:Antioxidants; D001711:Biotransformation; D005609:Free Radicals; D006878:Hydroxides; D017665:Hydroxyl Radical; D066298:In Vitro Techniques; D008163:Luminescent Measurements; D010636:Phenols / Q000494:pharmacology*; D012459:Salicylates / Q000494:pharmacology; D020156:Salicylic Acid; D013329:Structure-Activity Relationship; D012460:Sulfasalazine / Q000031:analogs & derivatives / Q000494:pharmacology; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors
chemical_list: D000975:Antioxidants; D005609:Free Radicals; D006878:Hydroxides; D010636:Phenols; D012459:Salicylates; D000632:Aminopyrine; D017665:Hydroxyl Radical; D012460:Sulfasalazine; D014969:Xanthine Oxidase; D020156:Salicylic Acid