- Synthesis of Triafulvene Precursors for Retro-Diels-Alder Reactions
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Triafulvene precursors exo-15 and endo-15 have been prepared by addition of dibromocarbene to benzobarrelene 12 followed by a lithium-halogen exchange, methylation, and elimination of HBr (12 -> 13 -> 14 -> 15), (Scheme 2).Gas-phase pyrolysis of exo/endo-mixtures of 15 above 400 deg gave minor amounts of naphthalene (16), traces of a hydrocarbon C4H4 identified by MS (presumably triafulvene 1) and predominantly (36percent) the isomerization product 17 (Scheme 3).In a second synthetic approach the well-known cycloheptatriene-norcaradiene equilibrium of type 26->/2,4>nona-6,8-dienes 31 (Scheme 5).However, numerous elimination experiments 31 -> 9 failed so far.The structure of two rearrangement products 33 and 34 (Scheme 6) has been elucidated.
- Krebs, Juerg,Guggisberg, Dominik,Staempfli, Urs,Neuenschwander, Markus
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- Compound for treatment or prevention of breast cancer
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The invention discloses a compound for treatment or prevention of breast cancer, specifically a 2-phenyl benzoselenazole compound, its pharmaceutically acceptable salt and easily hydrolysable prodrug. The invention further discloses a pharmaceutical composition containing the compounds and use of the compound in preparation of drugs for treatment or prevention of breast cancer in mammals. The compound involved in the invention can effectively inhibit or reduce mammalian breast cancer cell growth or proliferation, at the same time, the compound has no inhibiting effect on the growth of partial test cells except for breast cancer cells and has good selectivity. The compound shows more obvious efficacy, high selectivity, low toxicity and small side effect. (formula of the compound).
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Paragraph 0059-0062
(2018/02/04)
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- Sensitive near-infrared fluorescent probes for thiols based on Se-N bond cleavage: Imaging in living cells and tissues
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Cy-NiSe and Cy-TfSe were designed and synthesized as sensitive near-infrared (NIR) fluorescent probes for detecting thiols on the basis of Se-N bond cleavage both in cells and in tissues. Since a donor-excited photoinduced electron transfer (d-PET) process occurs between the modulator and the fluorophore, Cy-NiSe and Cy-TfSe have weak fluorescence. On titration with glutathione, the free dye exhibits significant fluorescence enhancement. The two probes are sensitive and selective for thiols over other relevant biological species. They can function rapidly at pH 7.4, and their emission lies in the NIR region. Confocal imaging confirms that Cy-NiSe and Cy-TfSe can be used for detecting thiols in living cells and tissues. Turn-on fluorescent probes Cy-NiSe and Cy-TfSe, which show weak fluorescence due to donor-excited photoinduced electron transfer, release near-infrared fluorescent dye Cy7-MeAm on cleavage of the Se-N bond by thiols. Thus, they can be used for real-time imaging of thiols such as glutathione in living cells and tissue (see figure). Copyright
- Wang, Rui,Chen, Lingxin,Liu, Ping,Wang, Yunqing,Zhang, Qin
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p. 11343 - 11349,7
(2012/12/12)
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- Synthesis of novel 5-aryl-1H-tetrazoles
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In this study phenylselenocyanate and some of its derivatives (o-Cl, p-Cl, p-Br, o-NO2, p-NO2, o-CH3, p-CH3, o-COOH, p-COOH, p-OCH3 substituted) were synthesized (3a-3j). The synthesized compounds were converted to 5-aryl-1H-tetrazole (4a-4j), by Et 3N · HCl-NaN3 in toluene, which are a new series of phenylselanyl-1H-tetrazoles. The structure of all the presently synthesized compounds were confirmed using spectroscopic methods (FTIR, 1H NMR, MS).
- Oezkan, Hamdi,Yavuz, Serkan,Disli, Ali,Yildirir, Yilmaz,Tuerker, Lemi
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p. 255 - 258
(2008/02/08)
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- Synthesis of diselenadiazafulvalenes and influence of steric strain on their anodic behavior
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A novel family of π-donor molecules, the diselenadiazafulvalenes (DSeDAFs), is presented. The synthetic approach to these donors, from o-nitroaniline, allows the formation of N,N′-dimethyldibenzo DSeDAF and N,N′-ethylenedibenzo DSeDAF. Comparative electrochemical study of these π-donor molecules demonstrates their excellent donor ability and the stabilizing effect of the ethylene bridge on the cation radical species.
- Casar, Zdenko,Leban, Ivan,Marechal, Alenka Majcen-Le,Lorcy, Dominique
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p. 1568 - 1573
(2007/10/03)
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- Benzselenirene as Short-lived Intermediate in the Pyrolysis of 1,2,3-Benzoselenodiazole to 6-Fulvenselone
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In the pyrolysis of 1,2,3-benzoselenodiazole using a short-distance furnace, a short-lived intermediate is detected photoelectron spectroscopically.Mass spectra recorded under similar conditions suggest an isomer C6H4Se rearranging to the more stable final product 6-fulveneselone.The ionization pattern obtained by computerized spectra stripping is assigned to benzselenirene by molecular radical cation state comparison based on MNDO calculations. - Keywords: PE Spectra, Short-lived Intermediates, Selenium Compounds
- Bock, Hans,Aygen, Sitki,Solouki, Bahman
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p. 611 - 615
(2007/10/02)
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