title: Enhancement of antioxidant activity of p-alkylaminophenols by alkyl chain elongation.
abstract: The initial finding that the p-methylaminophenol (6) exhibited antioxidant activity led us to investigate whether the length of alkyl chains linked to the aminophenol residue might affect antioxidative activity. Therefore, we synthesized p-butylaminophenol (5), p-hexylaminophenol (4), p-octylaminophenol (3), and p-methoxybenzylaminophenol (7). All p-alkylaminophenols quenched alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radicals, with 7 being the most potent DPPH radical scavenger. Lipid peroxidation by rat liver microsomes was reduced by p-alkylaminophenols in dose- and aminophenol alkyl chain length-dependent fashion (3>4>5>6), with 3 being the most potent lipid peroxidation inhibitor, at approximately 350-fold higher potency than 6. These results indicate that elongation of alkyl chains in p-alkylaminophenols may increase antioxidative activity, and that p-alkylaminophenols may potentially be useful in the development of antioxidants.
authors.affiliation: Faculty of Pharmaceutical Sciences, Hoshi University, 4-41 Ebara 2-Chome, Shinagawa-ku, 142-8501 Tokyo, Japan. t-noriko@hoshi.ac.jp
authors.forename: Noriko
authors.initials: N
authors.lastname: Takahashi
authors.forename: Kayoko
authors.initials: K
authors.lastname: Tamagawa
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kubo
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Fukui
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Wakabayashi
authors.forename: Toshio
authors.initials: T
authors.lastname: Honda
mesh_terms: D000627:Aminophenols / Q000737:chemistry* / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008862:Microsomes, Liver / Q000187:drug effects / Q000502:physiology; D051381:Rats
chemical_list: D000627:Aminophenols; D000975:Antioxidants