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(11,13-Dimethyl-1,4,7,10-tetraazacyclotrideca-10,13-dienato)copper(II) perchlorate
Xiao-qiang He
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809001664
Abstract: The title complex, [Cu(C11H21N4)]ClO4, comprises [CuII(L)]+ (L = 11,13-dimethyl-1,4,7,10-tetraazacyclotrideca-10,12-dienate) cations and a perchlorate anion. The Cu atom is located on a twofold crystallographic symmetry axis and is coordinated by four N atoms in a slightly distorted square-planar geometry. Intermolecular N—H...O hydrogen bonds are present.
Preparation of 11-Hydroxylated 11,13-Dihydrosesquiterpene Lactones  [cached]
Howard G. Pentes,Francisco A. Macias,Nikolaus H. Fischer
Revista de la Sociedad Química de México , 2003,
Abstract: Se llevaron a cabo hidroxilaciones de las posiciones α- del grupo carbonilo lactónico en cuatro esqueletos diferentes de 11,13- dihidro- derivados de lactonas sesquiterpénicas (germacranólidas, eudesmanólidas, guayanólidas y elemanólidas), mediante la generación del enolato con LDA y su atrapamiento con oxígeno gaseoso o con un agente oxidante quiral, (canforilsulfonil)aziridina. Las oxidaciones con oxígeno no fueron estereo-específicas y generaron las hidroxi-lactonas 11α- y 11β- en rendimientos combinados que fluctúan entre 13 al 47 %, junto con cetonas nor-sesquiterpénicas, que se forman probablemente por la descomposición de los aniones hidroperóxidos intermediarios. La hidroxilación de la germacranólida 11,13-dihidropartenólida, con (+)- o (-)- (canforilsulfonil)-aziridina produjo la 11β-hidroxi-lactona exclusivamente (66-72 %), sin detectarse la cetona nor-sesquiterpénica.
10α-Hydroxy-13-{[4-(4-methoxyphenyl)piperazin-1-yl]methyl}-4,9-dimethyl-3,8,15-trioxatetracyclo[10.3.0.02,4.07,9]pentadecan-14-one  [cached]
Mohamed Moumou,Ahmed Benharref,Jean Claude Daran,Rachid Outouch
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812005818
Abstract: The title compound, C26H36N2O6, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylen-3,14-dioxa-tricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from fused five- and ten-membered rings with two additional epoxy ring systems and a methoxyphenylpiperazine group as a substituent. The ten-membered ring adopts an approximate chair–chair conformation, while the piperazine ring displays a chair conformation and the five-membered ring shows an envelope conformation with the C atom closest to the hydroxy group forming the flap. The molecular conformation is determined by an O—H...N hydrogen bond between the hydroxy group and a piperazine N atom. The crystal structure is built up by weak C—H...O interactions.
9-Hydroxy-4,8-dimethyl-12-(piperidin-1-ylmethyl)-3,14-dioxatricyclo[9.3.0.02,4]tetradec-7-en-13-one  [cached]
Mohamed Moumou,Ahmed Benharref,Jean-Claude Daran,Ahmed Elhakmaoui
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811038803
Abstract: The title compound, C20H31NO4, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylen-3,14-dioxa-tricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from fused five-and ten-membered rings with the pipyridin-1-yl-methyl group as a substituent. The ten-membered ring adopts an approximate chair–chair conformation, while the six-membered ring display a chair conformation and the five-membered ring an envelope conformation with the C(H)–C–C(H) atom at the flap. The dihedral angle between the ten-membered ring and the lactone ring is 21.7 (4)°. The molecular conformation is stabilized by an O—H...N hydrogen bond and the crystal structure is stabilized by weak intermolecular C—H...O interactions.
10α-Hydroxy-4,9-dimethyl-13-(pipyridin-1-ylmethyl)-3,8,15-trioxatetracyclo[10.3.0.02,4.07,9]tetradecan-14-one
Mohamed Moumou,Ahmed Benharref,Abdelghani Oudahmane,Ahmed Elhakmaoui
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811042644
Abstract: The title compound, C20H31NO5, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylen-3,14-dioxa-tricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The molecule is built up from fused five-and ten-membered rings with the pipyridin-1-yl-methyl group as a substituent. The ten-membered ring adopts an approximate chair–chair conformation, while the six- and five-membered rings display chair and envelope conformations, respectively. The dihedral angle between the mean planes of the ten-membered ring and the lactone ring is 20.8 (3)°. An intramolecular O—H...N hydrogen-bond occurs. The crystal structure is stabilized by weak intermolecular C—H...O hydrogen bonds.
9β-Hydroxy-6,9-dimethyl-3-methylene-3a,4,8,9,9a,9b-hexahydroazuleno[4,5-b]furan-2(3H)-one  [cached]
Mohamed Moumou,Ahmed Benharref,Jean Claude Daran,Fouad Mellouki
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812000165
Abstract: The title compound, C15H18O3, was synthesized from 9α-hydroxyparthenolide (9α-hydroxy-4,8-dimethyl-12-methylen-3,14-dioxa-tricyclo[9.3.0.02,4]tetradec-7-en-13-one), which was isolated from the chloroform extract of the aerial parts of Anvillea radiata. The seven-membered ring of the title compound shows a chair conformation, while the five-membered rings exibit different conformations, viz a twisted one for the lactone ring and an envelope conformation for the other five-membered ring with the C atom closest to the hydroxy group forming the flap. In the crystal, O—H...O hydrogen bonds connect molecules into dimers that are interconnected by C—H...O interactions, producing supramolecular chains along the b axis.
Effects of dimethyl fumarate on neuroprotection and immunomodulation
Philipp Albrecht, Imane Bouchachia, Corinna Zimmermann, Harald H Hofstetter, Zsuzsa Kovacs, Nadine Henke, Dmitrij Lisak, Andrea Issberner, Jan Lewerenz, Pamela Maher, Norbert Goebels, Kim Quasthoff, Anne-Kathrin Mausberg, Hans-Peter Hartung, Axel Methner
Journal of Neuroinflammation , 2012, DOI: 10.1186/1742-2094-9-163
Abstract: We determined time- and concentration-dependent effects of dimethyl fumarate and its metabolite monomethyl fumarate on viability in a model of endogenous neuronal oxidative stress and clarified the mechanism of action by quantitating cellular glutathione content and recycling, nuclear translocation of transcription factors, and the expression of antioxidant genes. We compared this with changes in the cytokine profiles released by stimulated splenocytes measured by ELISPOT technology and analyzed the interactions between neuronal and immune cells and neuronal function and viability in cell death assays and multi-electrode arrays. Our observations show that dimethyl fumarate causes short-lived oxidative stress, which leads to increased levels and nuclear localization of the transcription factor nuclear factor erythroid 2-related factor 2 and a subsequent increase in glutathione synthesis and recycling in neuronal cells. Concentrations that were cytoprotective in neuronal cells had no negative effects on viability of splenocytes but suppressed the production of proinflammatory cytokines in cultures from C57BL/6 and SJL mice and had no effects on neuronal activity in multi-electrode arrays.These results suggest that immunomodulatory concentrations of dimethyl fumarate can reduce oxidative stress without altering neuronal network activity.
A short synthesis of (±)-cherylline dimethyl ether  [cached]
Bhima Y. Kale,Ananta D. Shinde,Swapnil S. Sonar,Bapurao B. Shingate
Beilstein Journal of Organic Chemistry , 2009, DOI: 10.3762/bjoc.5.80
Abstract: A synthesis of (±)-cherylline dimethyl ether is reported. The key steps involved are Michael-type addition, radical azidonation of an aldehyde, Curtius rearrangement, and reduction of an isocyanate intermediate followed by Pictet–Spengler cyclization.
Dimethyl phthalate biodegradation by Dunaliella tertiolecta
Yan Hai,Liu Yun xia
环境科学学报(英文版) , 1998,
Abstract: Dunaliella tertiolecta has an ability to biodegrade dimethyl phthalate(DMP) was found in this study, and the average of the biodegradation rates were 11.3 mg/(L·d) and 30.5 mg/(L·d), and the average of the phthalic acid (PA) production rates were 1.5 mg/(L·d) and 3.6 mg/(L·d), for initial 100 mg/L and 300 mg/L DMP, respectively. The larger amount of accumulation by D. tertiolecta under higher DMP concentration may be responsible for the increase of biodegradation rate, and one of products of DMP biodegradation by D. tertiolecta may be PA. By fitting the process of DMP biodegradation by D. tertiolecta with a kinetic equation newly suggested, the standard deviations between calculated and observed values were 2.5 mg/L and 5.7 mg/L, respectively.
Electrogenerated chemiluminescence of violanthrone in dimethyl sulfoxide  [cached]
K. Hansongnern,P. Chooto,P. Amornpitoksuk
International Journal of Photoenergy , 1999, DOI: 10.1155/s1110662x99000240
Abstract: Violanthrone is an anthraquinone vat dye, which is resistant to photochemical damage. Most previous work has concentrated on its chemiluminescence properties. In this report, electrogenerated chemiluminescence (ECL) of violanthrone has been investigated in dimethyl sulfoxide with 0.1M of tetraethylammonium bromide as electrolyte. Violanthrone luminesces in the potential range between 0.0V and -4:0 V. At the sweep rate 1000 mV/s, the intensity of the violanthrone ECL is about 2% of that of tris(2,2 ¢ € 2-bipyridine) ruthenium(II) ion under the same conditions. It was found that bromine was also produced during the ex- periment, leading to the conclusion that the luminescence arises from the reaction between radical anion of violanthrone and molecular bromine. The mechanism is discussed in detail.
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