Results 101 to 110 of about 435 (116)

Chemiluminescence in decomposition of bridged 1,2,4,5-tetraoxanes catalyzed by ferrocene

Mendeleev Communications, 2017
Chemiluminescence was observed in ferrocene-catalyzed decomposition of bridged 1,2,4,5-tetraoxanes, namely, 2,3,5,6-tetraoxabicyclo[2.2.1]heptanes. The chemi- and photoluminescence spectra revealed the main products and luminescence emitters to be β-diketones.
Ramil G. Bulgakov, Dim I. Galimov, Alexander O. Terent'ev, D. R. Gazeeva   +3 more
openaire   +2 more sources

The effect of the structure of mixed tetraoxanes on their chromatographic behavior on different adsorbents

Journal of Planar Chromatography – Modern TLC, 2004
The retention behavior of 29 biologically active compounds, mixed 1,2,4,5-tetraoxanes, has been investigated by thin-layer chromatography on unmodified silica, CN-silica, and RP-18-silica. The binary mobile phases ethyl acetate-petroleum ether and ethyl acetate-toluene were used under normal-phase conditions and water-organic modifier (methanol ...
Gaica, Sandra, Opsenica, Dejan, Šolaja, Bogdan, Tešić, Živoslav, Milojković-Opsenica, Dušanka   +4 more
openaire   +4 more sources

Radiation‐induced solid state polymerization of tetraoxane

Journal of Polymer Science Part B: Polymer Letters, 1963
The radioinduced polymerization of tetraoxane is reported and compared with that of trioxane. Under gamma irradiation at 80 deg C and at a dose rate of 2.5 x 10/sup 4/ r/hr, tetraoxane became gradually opaque. After 18 hr irradiation a polymer crystal with the shape of the monomer crystal was obtained at 94% conversion. However, no polymer was obtained
M. Nishii, H. Ochi, Koichiro Hayashi, Y. Miyake, S. Okamura   +4 more
openaire   +2 more sources

Synthesis of Novel Conjugates of Tetraoxane Endoperoxide with Bis(Quaternary Ammonium Salts)

Bioscience, Biotechnology, and Biochemistry, 2009
Novel water-soluble conjugates of 1,2,4,5-tetraoxane bis(quaternary ammonium salts) were synthesized in a relatively stable crystalline form via four steps starting from methyltrioxorhenium-catalyzed endo-peroxidation of ethyl 4-oxocyclohexanecarboxylate with hydrogen peroxide in hexafluoro-2-propanol.
Shuhei Nakajima, Minoru Izumi, Hirotaka Furukawa, Arnold N. Onyango, Naomichi Baba, Michiyo Kobayashi, Hye Sook Kim, Naokazu Kumura, Yusuke Wataya   +8 more
openaire   +3 more sources

Mixed steroidal tetraoxanes induce apoptotic cell death in tumor cells

Investigational New Drugs, 2008
In this study we investigated the antiproliferative activity of six mixed steroidal tetraoxanes against various tumor cell lines, the toxicity against normal peripheral blood mononuclear cells (PBMC), and the mode of HeLa cell death induced by these compounds.
Žižak, Željko, Juranić, Zorica, Opsenica, Dejan, Šolaja, Bogdan   +3 more
openaire   +5 more sources

Different behavior of artemisinin and tetraoxane in the oxidative degradation of phospholipid

Chemistry and Physics of Lipids, 2009
The reaction of trioxane and tetraoxane endoperoxides with unsaturated phospholipid 1 in the presence of Fe(II) was investigated in the absence of oxygen by means of tandem ESI-MS analysis. The spectral analyses for the reaction mixtures showed that artemisinin 2 with a trioxane structure gave no peak except that for the remaining intact phospholipid 1
Hirotaka Furukawa, Minoru Izumi, Hye Sook Kim, Arnold N. Onyango, Hideyuki Ito, Naomichi Baba, Tsutomu Hatano, Naokazu Kumura, Shuhei Nakajima, Yusuke Wataya   +9 more
openaire   +3 more sources

Steroidal geminal dihydroperoxides and 1,2,4,5-tetraoxanes: Structure determination and their antimalarial activity

Steroids, 1996
Cholestane-derived gem-dihydroperoxides and tetraoxanes were synthesized starting from 5 alpha- and 5 beta-cholestan-3-ones by acid-catalyzed addition of hydrogen peroxide to the ketone. They were characterized by IR, NMR, and mass spectroscopy analysis aided by molecular mechanics calculations, and, in the instance of 5 beta-cholestane-3 alpha,3 beta ...
Todorović, Nina, Stefanović, Milutin, Tinant, Bernard, Declercq, Jean-Paul, Makler, Michael T, Šolaja, Bogdan   +5 more
openaire   +5 more sources

Retracted: Tetraoxanes: Synthetic and medicinal chemistry perspective

Medicinal Research Reviews, 2011
AbstractThe following article from Medicinal Research Reviews, Tetraoxanes: Synthetic and medicinal chemistry perspective by Nitin Kumar, Ram Singh, Diwan S. Rawat, published online on 21 December 2009 in Wiley Online Library (http://www.wileyonlinelibrary.com), has been retracted by agreement between the authors, the journal Editor in Chief, Binghe ...
Nitin Kumar, Ram Singh, Diwan S. Rawat
openaire   +2 more sources

Access to Nonsymmetrical Tri- and Tetraoxanes with Silica Sulfuric Acid [PDF]

Synfacts, 2021
Paul Richardson, Johnny W. Lee
openaire   +1 more source

Polymerization of tetraoxane by radical initiators

Journal of Polymer Science Part B: Polymer Letters, 1971
Yoshiaki Nakase, Akihiko Ito, Masaru Yoshida   +2 more
openaire   +2 more sources