38582-76-2Relevant academic research and scientific papers
Nitronyl nitroxide as a coupling partner: Pd-mediated cross-coupling of (nitronyl nitroxide-2-ido)(triphenylphosphine)gold(i) with aryl halides
Tanimoto, Ryu,Suzuki, Shuichi,Kozaki, Masatoshi,Okada, Keiji
, p. 678 - 680 (2014/05/20)
A cross-coupling reaction using nitronyl nitroxide (NN) as a coupling partner was developed: Refluxing a mixture of [AuI(NN-2-ido)(PPh3)] and aryl iodide (ArI) in THF in the presence of 10 mol% [Pd(PPh3)4] produced a cross-coupling product NN-Ar in a high yield. This method allowed the direct introduction of the NN radical onto various poly- and heterocyclic aromatic rings.
Novel 1-oxyl-2-substitutedphenyl-4,4,5,5-tetramethylimidazolines: Synthesis, selectively analgesic action, and QSAR analysis
Zhao, Ming,Li, Zheng,Peng, Li,Tang, Yu-Rong,Wang, Chao,Zhang, Ziding,Peng, Shiqi
, p. 2815 - 2826 (2007/10/03)
Based on the knowledge that imidazoline can result in analgesic action due to its selective binding with the prostacyclin receptor, 20 1-oxyl-2-substitutedphenyl-4,4,5,5-tetramethylimidazolines (3a-t) were prepared in moderate yields. At 0.13 mmol/kg dose, their in vivo analgesic activities were evaluated after the mice were administered at 30, 60, 90, and 150 min. Compared with the pain threshold (12.27 ± 9.56-17.71 ± 7.00%) of normal saline (NS) receiving mice, the pain threshold (23.42 ± 8.14% to 102.58 ± 10.66%) of 3a-t receiving mice increases significantly. Considering a prostacyclin receptor targeting analgesic agent usually had bleeding action and to appraise the bleeding risk, the in vivo tail bleeding time of 1.30 mmol/kg 3a-t receiving mice was found to be ranged from 116.3 ± 8.2 s to 120.3 ± 9.2 s, which was substantially equal to that (117.8 ± 8.4 s to 119.0 ± 8.6 s) of NS receiving mice. Based on the possibility of imidazoline acting as vasodilator, the in vitro vasorelaxations of 3a-t were tested using the rat aortic strip model. When the aortic strip contracted by noradrenaline (NE, final concentration 10-7 mol/l) was treated with 3a-t (final concentration 5 × 10-4 mol/l), only lower percentage inhibitions (6.55 ± 5.70-37.40 ± 4.07%) were recorded, implying that the vasorelaxation of 3a-t was neglectable. By selecting appropriate molecular descriptors generated from e-dragon server, the QSAR model of the analgesic activities of 3a-t was constructed using the multiple linear regression method. The established QSAR model showed reasonable accuracy and thus it is promising to be used for screening new 1-oxyl-2-substitutedphenyl-4,4,5,5-tetramethylimidazoline derivatives as analgesic agents.
Novel 2-substituted nitronyl nitroxides as free radical scavengers: Synthesis, biological evaluation and structure-activity relationship
Wu, Yihui,Bi, Lanrong,Bi, Wei,Li, Zeng,Zhao, Ming,Wang, Chao,Ju, Jingfang,Peng, Shiqi
, p. 5711 - 5720 (2007/10/03)
To develop more potent small molecules with enhanced free radical scavenger properties, we designed and synthesized a series of nitronyl nitroxide derivatives 4a-h. A lead compound 4f was discovered based on Ach-induced vascorelaxation assay. Further chemical modification based on this scaffold provided a new series of 2-substituted phenylnitronyl nitroxide derivatives 6a-s. The newly synthesized compounds 6a-s possess improved radical scavenger's activity based on PC12 cell survival assay. Compounds 6g,n,o, and s are some of the most potent compounds in terms of NO, H2O2, and OH scavenging ability. 2-Substitued phenylnitronyl nitroxides had a higher radical scavenging activity with the electron-donating group (EDG). In contrast, the introduction of electron-withdrawing group (EWG) to the aromatic ring led to a dramatic decrease in its radical scavenging activity. These results suggest that the electron-donating group (EDG) of the aromatic ring may be an important factor influencing the radical scavenging behavior of these compounds, and the potency of free radical scavenging activity largely depended on the position and electronic properties of the phenyl ring substituents. The enhanced radical scavenging capacities of the novel 2-substituted nitronyl nitroxides may be potential drug leads against the deleterious action of ROS (reactive oxygen species)/RNS (reactive nitrogen species).
Design, preparation, and electronic structure of high-spin cation diradicals derived from amine-based spin-polarized donors
Sakurai, Hiromi,Izuoka, Akira,Sugawara, Tadashi
, p. 9723 - 9734 (2007/10/03)
Amine-based donor radicals, such as dimethylamino-, diethylamino-and morpholinonitronyl nitroxides, were synthesized, and their donor abilities were examined by cyclic voltammetry. ESR spectra of the singly oxidized donor radicals showed ground state triplet signals derived from the cation radicals of these donor radicals. The result was interpreted by the presence of the ferromagnetic coupling between the generated π-spin and the localized unpaired electron on the radical unit. According to the molecular orbital calculations, the ferromagnetic coupling between these two spins is originated from the space-sharing nature between SOMO which is localized on the radical unit and SOMO' which is derived from HOMO of the donor radical upon one-electron oxidation. Therefore, the cation-radicals of these donor radicals can be regarded as a heteroanalogue of trimethylenemethane. p-and m-dimethylaminophenyl nitronyl nitroxides were synthesized in order to expand the π-electronic structure of the donor unit, and the singly oxidized species were also found to afford triplet ESR signals. The origin of the ferromagnetic coupling of these aminophenyl nitronyl nitroxides was discussed on the same basis. Charge transfer complexes of some of the donor radicals with chloranil or 2,3-dichloro5,6-dicyano-1,4-benzoquinone were prepared, and the conducting and magnetic properties were examined.
