1044254-00-3Relevant academic research and scientific papers
Structure-reactivity relationship of piperidine nitroxide: Electrochemical, ESR and computational studies
Yamasaki, Toshihide,Mito, Fumiya,Ito, Yuko,Pandian, Sokkar,Kinoshita, Yuichi,Nakano, Koji,Murugesan, Ramachandran,Sakai, Kiyoshi,Utsumi, Hideo,Yamada, Ken-Ichi
scheme or table, p. 435 - 440 (2011/04/19)
We have synthesized several nitroxides with different substituents which vary the steric and electronic environment around the N-O moiety and have systematically investigated the role of substituents on the stability of the radicals. Our results demonstrated the reactivity toward ascorbate correlates with the redox potential of the derivatives. Furthermore, ab initio calculations also indicated a correlation between the reduction rate and the computed singly occupied molecular orbital-lowest unoccupied molecular orbital energy gap, but not with solvent accessible surface area of the N-O moiety, supporting the experimental results and suggesting that the electronic factors largely determine the radicals' stability. Hence, it is possible to perform virtual screening of nitroxides to optimize their stability, which can help to rationally design novel nitroxides for their potential use in vivo.
Effective 2,6-substitution of piperidine nitroxyl radical by carbonyl compound
Sakai, Kiyoshi,Yamada, Ken-ichi,Yamasaki, Toshihide,Kinoshita, Yuichi,Mito, Fumiya,Utsumi, Hideo
experimental part, p. 2311 - 2315 (2010/06/12)
Nitroxyl radicals (nitroxides) with unpaired electron are widely used as antioxidants, contrast agents, and spin probes. Although piperidine nitroxyl radicals have many applications, these are mainly tetramethylpiperidine compounds, and only a few reports consider the substitution of N-O surround as a reaction site, such as 2,2,6,6-tetrasubstituted piperidine nitroxyl radicals. Our results revealed that the 2,6-position of the 2,2,6,6-tetramethylpiperidin-4-one compound was substituted by cyclohexyl groups to produce 2,2,6,6-tetrasubstituted piperidin-4-one derivatives under mild reaction conditions. An interesting result was obtained by using 15N-labeled NH4Cl instead of 14NH4Cl: it gave 15N-labeled 2,2,6,6-tetrasubstituted piperidin-4-one-1-oxyls with a high 15N content. In conclusion, the new method for the synthesis of nitroxyl radicals readily yields 2,2,6,6-tetrasubstituted piperidin-4-one under mild conditions.
