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11.
Firouz Matloubi Moghaddam Zohreh Mirjafary Hamdollah Saeidian Behzad Koushki Foroushani Saghar Nourian 《合成通讯》2013,43(13):1941-1949
The synthesis of bicyclo[3.3.1]nonane systems is reported. The synthesis is based on the tandem 1,3-dinucleophilic addition of 4-hydroxy-2-quinolinone to quinolinium salts. 相似文献
12.
Mohammad Ghaffarzadeh Mohammad Bolourtchian Zohreh Hassanzadeh Fard Mohammad Reza Halvagar Farshid Mohsenzadeh 《合成通讯》2013,43(14):1973-1981
One‐step microwave‐assisted synthesis of phenylacetylenes 2a–j from the corresponding ketones 1a–j in the presence of a new reagent, PCl5–pyridine, is described. The reaction is carried out under a simple operational and experimental procedure, avoiding the use of the complicated and harsh multistep reaction. 相似文献
13.
J. L. Pore D. S. Cross C. Andreoiu R. Ashley G. C. Ball P. C. Bender A. S. Chester A. Diaz Varela G. A. Demand R. Dunlop A. B. Garnsworthy P. E. Garrett G. Hackman B. Hadinia B. Jigmeddorj A. T. Laffoley A. Liblong R. Kanungo B. Noakes C. M. Petrache M. M. Rajabali K. Starosta C. E. Svensson P. J. Voss Z. M. Wang J. L. Wood S. W. Yates 《The European Physical Journal A - Hadrons and Nuclei》2017,53(2):27
14.
Zohreh T. Farahbakhsh Christian Altenbach Wayne L. Hubbell 《Photochemistry and photobiology》1992,56(6):1019-1033
In stoichiometric amounts, the spin label N-tempoyl-(p-chloromercuribenzamide) reacts rapidly with one cysteine residue in membrane-bound bovine rhodopsin. This residue is distinct from the two reactive cysteines previously used as attachment sites for spectroscopic labels, and is on the external surface of the protein near the cytoplasmic membrane/aqueous interface. The spin-labeled side chain has revealed a light-induced conformational change in membrane-bound rhodopsin that is apparently not associated with protein aggregation. The changes are reversible upon the addition of 11-cis retinal, and the magnitude of the change is dependent on the identity of the phospholipid in the surrounding bilayer. Alteration of lipid composition has a much larger effect on bleached rhodopsin than rhodopsin itself, indicating that the former is more readily deformable in response to changes in bilayer properties. This is consistent with the loss of 11-cis retinal binding energy in opsin compared to rhodopsin. These results provide direct structural evidence that the conformation of a membrane protein can be modulated by the lipid properties. 相似文献
15.
The first asymmetric synthesis of α,β-disubstituted γ-phosphono sulfonates is reported. The key step is the Michael addition of a lithiated enantiopure sulfonate bearing an inexpensive chiral sugar auxiliary to α,β-unsaturated phosphonates in good diastereoselectivities. After chromatographic purification, the cleavage of the chiral sugar auxiliary proceeds without any epimerization or racemization to form the corresponding isopropyl sulfonate in very good overall yield (75%) and excellent diastereomeric and enantiomeric excess (de, ee ? 95%). 相似文献
16.
Firouz Matloubi Moghaddam Mostafa Kiamehr Salman Taheri Zohreh Mirjafary 《Helvetica chimica acta》2010,93(5):964-973
An efficient synthesis of polycyclic indole derivatives is achieved via domino Knoevenagel–hetero‐Diels–Alder reaction of O‐acrylated salicylaldehyde derivatives with dihydroindole‐2‐thiones in H2O as solvent. The products are formed in good‐to‐excellent yields with high regio‐ and stereoselectivity. 相似文献
17.
The synthesis of a series of benzoxazocines has been achieved in good yields by tandem C-alkylation and intramolecular O-alkylation of 1,3-dicarbonyl compounds with quinolinium salts. This is a novel example of the synthesis of eight-membered rings via a tandem process, which provides a method for the synthesis of medium-ring heterocycles. 相似文献
18.
Manuel M. Bentlohner Wilhelm Klein Zohreh H. Fard Laura‐Alice Jantke Thomas F. Fssler 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(12):3819-3824
The accessibility of triads with deltahedral Zintl clusters in analogy to fullerene–linker–fullerene triads is another example for the close relationship between fullerenes and Zintl clusters. The compound {[K(2.2.2‐crypt)]4[RGe9‐CHCH CHCH‐Ge9R]}(toluene)2 (R=(2Z,4E)‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl), containing two deltahedral [Ge9] clusters linked by a conjugated (1Z,3Z)‐buta‐1,3‐dien‐1,4‐diyl bridge, was synthesized through the reaction of 1,4‐bis(trimethylsilyl)butadiyne with K4Ge9 in ethylenediamine and crystallized after the addition of 2.2.2‐cryptand and toluene. The compound was characterized by single‐crystal structure analysis as well asNMR and IR spectroscopy. 相似文献
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