@article{oai:repo.qst.go.jp:00043088,
 author = {Saito, Keita and Takeshita, Keizo and Ueda, Junichi and Ozawa, Toshihiko and 齋藤 圭太 and 竹下 啓蔵 and 上田 順市 and 小澤 俊彦},
 journal = {Journal of Pharmaceutical Sciences},
 month = {},
 note = {The exposure of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPOL) to hydroxyl radical (.OH) led to the appearance of a new triplet ESR signal along with a reduction in the intensity of the TEMPOL signal.  The observed spectrum was in good agreement with the spectrum simulated with 4-oxo-2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPON) and TEMPOL, and the addition of sodium borohydride to the product solution led to the disappearance of the new signal.  These indicate the formation of TEMPON during the reaction.  A comparison of the concentration of TEMPON formed with that of nitroxyl compounds which lost the ESR signal showed that the rate of TEMPON formation is one-twelfth that of the paramagnetism-loss caused by .OH.  These results indicate that the 4-position of TEMPOL scavenges .OH to compensate for a decline in the scavenging activity of the nitroxyl group by the faster reaction with .OH, although the reaction is relatively slow.},
 title = {Two reaction sites of spin label, TEMPOL (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl), with hydroxyl radical},
 volume = {92},
 year = {2003}
}