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81.
Palladium-catalyzed oxidative alkynylation of alkenes using tert-propargylic alcohols as alkynylation reagents via C-C bond cleavage under an oxygen atmosphere affords the corresponding ene-yne compounds. 相似文献
82.
Magnetic phase transition in a heteromolecular hydrogen-bonded complex of nitronylnitroxide radicals
Hayakawa K Shiomi D Ise T Sato K Takui T 《The journal of physical chemistry. B》2005,109(19):9195-9197
An organic molecular acid-base complex has been synthesized from pyridine-substituted biradical 2 in a triplet (S = 1) ground state and a benzoic acid derivative of monoradical 3 with S = 1/2. The two constituent molecules are bound by an OH-N hydrogen bond in a crystalline solid state. The complex has been found to exhibit an antiferromagnetic phase transition at 5 K. The complex is the first example of a hydrogen-bonded heterospin, heteromolecular complex exhibiting a magnetic phase transition in purely organic molecule-based materials. 相似文献
83.
Takeji Takui Koichi Itoh Yasuhiro Waka Hajime Kawakami Wasuke Mori 《Chemical physics letters》1975,35(4):461-464
Magnetic circular dichroism of trapped electrons in frozen matrices has been observed for the first time. It is concluded that the excited state of trapped electrons solvated by water molecules at 77 K has orbital angular momentum whereas that of electrons solvated by ethanol molecules at 77 K does not. This indicates that the symmetry of the trapping potential in aqueous glass is high whereas that in ethanol glass is low. 相似文献
84.
85.
Akiko Hashimoto Takeji Takamura‐Enya Yoshimitsu Oda 《Photochemistry and photobiology》2019,95(6):1403-1411
Photodynamic therapy (PDT) is a widely used medicinal treatment for the cancer therapy that utilizes the combination of a photosensitizer (PS) and light irradiation. In this study, we synthesized two novel C60 fullerene derivatives, compounds 1 and 2 , with a psoralen moiety that can covalently bind to DNA molecules via cross‐linking to pyrimidine under photoirradiation. Along with several fullerene derivatives, the biological properties of several novel compounds have been evaluated. Compounds 1 and 2 , which have been shown to induce the production of hydroxyl radicals using several ROS detecting reagents, induced DNA strand breaks with relatively weak activities in the in vitro detection system using a supercoiled plasmid. However, the psoralen‐bound fullerene with carboxyl groups ( 2 ) only showed genotoxicity in the genotoxicity assay system of the umu test. Compound 2 was also seen to have cytotoxic activities in several cancer cell lines at higher doses compared to water‐soluble fullerenes. 相似文献
86.
Joachim Mohn Christina Biasi Samuel Bodé Pascal Boeckx Paul J. Brewer Sarah Eggleston Heike Geilmann Myriam Guillevic Jan Kaiser Kristýna Kantnerová Heiko Moossen Joanna Müller Mayuko Nakagawa Ruth Pearce Isabell von Rein David Steger Sakae Toyoda Wolfgang Wanek Sarah K. Wexler Naohiro Yoshida Longfei Yu 《Rapid communications in mass spectrometry : RCM》2022,36(13):e9296
87.
88.
One-electron reduction of kinetically stabilized dipnictenes: synthesis of dipnictene anion radicals
Sasamori T Mieda E Nagahora N Sato K Shiomi D Takui T Hosoi Y Furukawa Y Takagi N Nagase S Tokitoh N 《Journal of the American Chemical Society》2006,128(38):12582-12588
The redox behavior of kinetically stabilized dipnictenes, BbtE=EBbt [E = P, Sb, Bi; Bbt = 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris(trimethylsilyl)methyl]phenyl], was systematically disclosed using cyclic voltammetry and theoretical calculations. It was found that they showed reversible one-electron redox couples in the reduction region. The anion radical species of the Bbt-substituted diphosphene and distibene were successfully synthesized by the reduction of the corresponding neutral dipnictenes (BbtP=PBbt and BbtSb=SbBbt). Their structures were reasonably characterized by ESR, UV-vis, and Raman spectroscopy, and the distibene anion radical was structurally characterized by X-ray crystallographic analysis. 相似文献
89.