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971.
The β-glycosyl esters of cis-cinnamic acid were synthesized directly using Hannesian’s unprotected glycosyl donor and the carboxylic acid in toluene. This protocol does not require protecting groups on the glycosyl donors, and high stereoselectivity was achieved. The first synthesis of a potent allelochemical, 1-O-cis-cinnamoyl-β-d-glucopyranose, is also described. 相似文献
972.
Glucose oxidase (GOD) was encapsulated in vesicles containing a photoionizable Malachite Green leuconitrile derivative (MGL). Subsequent UV irradiation of MGL afforded the fusion of GOD- and glucose-encapsulating vesicles and thus decreased the concentration of glucose in the vesicles. The time dependence of the vesicle fusion was studied using fluorescent probe molecules. This phototriggered fusion could be instrumental in the development of a system for the production of nanometer-sized bioreactors. 相似文献
973.
Birendra Babu Adhikari Manju Gurung Hidetaka Kawakita Keisuke Ohto 《Journal of inclusion phenomena and macrocyclic chemistry》2011,71(3-4):479-487
Complexation behavior of plural ion-exchangeable p?Ct-butylcalix[5]arene pentacarboxylic acid derivative towards trivalent indium has been investigated along with its monomeric analog from weakly acidic media into chloroform. The cyclic structure of calixarene ligand providing certain cavity and cooperativity of functional groups significantly affect the complexation behavior and calixarene derivative is an excellent extractant over monomeric analog. The extraction mechanism is ion exchange and carboxylic acid groups are adequate functional sites for extraction. Mononuclear and/or polynuclear species of indium and monomeric or bridged dimeric species of calixarene are involved in complexation and the composition of extracted complex varied with solution pH. One mole of calix[5]arene derivative tend to extract 3.5 mol of indium. The loaded indium was quantitatively back extracted with 1 mol dm?3 hydrochloric acid solution. 相似文献
974.
Rao KP Kondo M Sakamoto R Kusamoto T Nishikawa M Kume S Nihei M Oshio H Nishihara H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(50):14010-14019
The donor-acceptor-donor (D-A-D) conjugated molecules 1,4-bis(diarylaminophenylethynyl)anthraquinone (1,4-Am(2)Aq) and 1,4-bis(ferrocenylethynyl)anthraquinone (1,4-Fc(2)Aq), undergo a double proton cyclization reaction with bis(trifluoromethanesulfone)imide acid (TFSIH) to yield 1,4-bis(diarylaminophenyl or ferrocenyl) dipyrylium salts [1,4-R(2)Pyl(2)](TFSI)(2) (R=Am or Fc) with novel planar pentacyclic structures similar to the aromatic benzo[e]pyrene-type skeleton. [1,4-Am(2)Pyl(2)](TFSI)(2) could be reduced to give the neutral molecule [1,4-Am(2)Pyl(2)](0), which is stable and maintains the benzo[e]pyrene-type skeleton. To the best of our knowledge, this is the first oxygen-atom-containing polycyclic aromatic hydrocarbon with 22 (4n+2) π-electrons. The obtained condensed-ring benzo[e]pyrene-type skeleton compounds show physical and chemical properties that are significantly different from those of [1,5-Am(2)Pyl(2)](TFSI)(2), which has a perylene-type skeleton. 相似文献
975.
976.
977.
978.
Ito Y Tomiyasu Y Kawanabe T Uemura K Ushimizu Y Nishino H 《Organic & biomolecular chemistry》2011,9(5):1491-1507
Cyclophane-type macrocyclic compounds from 21 to 56 members having two fused dihydrofuran rings were synthesized by the manganese(III)-mediated oxidation of terminal dienes with bis(3-oxobutanoate)s containing aromatics. The reaction detail, characterization and reaction pathways are described. 相似文献
979.
Nihei M Takahashi N Nishikawa H Oshio H 《Dalton transactions (Cambridge, England : 2003)》2011,40(10):2154-2156
Iron(II) complexes with neutral and oxidized tetrathiafulvalene (TTF) moieties were prepared and X-ray crystallographic analyses, magnetic and electrical resistivity measurements suggested an interaction of spin transition and electrical conductivity. 相似文献
980.
Arikawa Y Matsumoto N Asayama T Umakoshi K Onishi M 《Dalton transactions (Cambridge, England : 2003)》2011,40(10):2148-2150
The hydroxido-bridged dinuclear ruthenium complex 4, which is supported by Tp ligands, has been prepared from protonation of the oxido-bridged dinuclear ruthenium complex 3. Additional protonation of 4, affording the aqua-bridged dinuclear ruthenium complex 5 in situ, and subsequent treatment with NO gave rise to the dicationic dinitrosyl complex 2. These indicate completion of the NO reduction cycle on the dinuclear ruthenium complex. 相似文献