@article{oai:repo.qst.go.jp:00045941,
 author = {Kobayashi, Shigeki and Waki, Tsukasa and Nakanishi, Ikuo and Matsumoto, Kenichiro and Anzai, Kazunori and 中西 郁夫 and 松本 謙一郎},
 issue = {11},
 journal = {Chemical & Pharmaceutical Bulletin},
 month = {Aug},
 note = {New potent antioxidants conjugating the catechol (=pyrocatechol; pyrCat) group to two N-termini of modified double-stranded tyrosine residues were synthesized and showed radical-scavenging activity with 2,2-diphenyl-1-picrylhydrazyl radical (DPPH radical) as a free radical model, second-order rate constants for the DPPH radical-scavenging reaction, and the results from electron spin resonance (ESR) studies.  It was found that the tyrosine (Tyr) residue and pyrCat containing new antioxidants developed in the study have about 3-20 times more potent antioxidative activity than Trolox, pyrCat, and L-ascorbic acid (VC).  In order to elucidate the relationship between antioxidative activity and the molecular orbital states, and to design potent antioxidants we present an interesting approach using an absolute hardness-absolute electronegativity diagram based on chemical hardness.  It was shown that quantum chemicals were required to develop potent antioxidants.},
 pages = {1442--1446},
 title = {Potent 2,2-Diphenyl-1-picrylhydrazyl Radical-Scavenging Activity of Novel Antioxidants, Double-Stranded Tyrosine Residues Conjugating Pyrocatechol},
 volume = {58},
 year = {2010}
}