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101.
102.
Saab AM Lampronti I Borgatti M Finotti A Harb F Safi S Gambari R 《Natural product research》2012,26(23):2227-2231
There are four kinds of Cedar: Cedrus libani naturally occurring in Lebanon, Syria and Turkey, Cedrus atlantica in Morocco and Algeria, Cedrus brevefolia in Cyprus Island and Cedrus deodara which is distributed in Himalayan Mountains. Wood essential oils obtained from C. libani, C. atlantica and C. deodara were tested for the inhibition of K562 cell proliferation and for the induction of erythroid differentiation. The wood essential oils of C. libani, C. atlantica and C. deodara inhibited the proliferation of the K562 cell line exhibiting IC(50) values 23.38?±?1.7, 59.37?±?2.6 and 37.09?±?1.4?μg?mL(-1), respectively. Meanwhile, C. libani wood oils induced a percentage of erythroid differentiation of 15?±?2% at concentration 5?μg?mL(-1). Cedrus deodara wood oil indicated a percentage of erythroid differentiation of 20?±?2% at concentration 25?μg?mL(-1) and C. atlantica wood oils showed a percentage of erythroid differentiation of 12?±?1.8% at concentration 10?μg?mL(-1). 相似文献
103.
Reduction in situ of WCl4(MeCN)2 with zinc in the presence of diazadiene ligands 1b-f is reported and produces a series of diamagnetic complexes (DAD)WCl22b-f. All complexes were characterized by 1H, 13C NMR and IR spectroscopic data. The crystal structures of complexes 2b and 2e were solved by X-ray diffraction methods. 相似文献
104.
A new helically chiral hexacyclic system, bearing an acetoxymethyl group, was prepared from a simple naphthalene building block in good yield and purity, via a four-step sequence involving palladium-catalysed Heck couplings and oxidative photocyclizations. Suitable crystals of the latter indicate that its conformation closely resembles that of unsubstituted [6]helicene, whose idealized symmetry is C2. The optical properties of the hexacyclic helicene were investigated and show interesting behaviour. 相似文献
105.
Mouna Ferchichi Erwann JeanneauBernard Fenet Faouzi MeganemUlrich Darbost Isabelle Bonnamour 《Tetrahedron letters》2012,53(32):4047-4050
The synthesis of a series of six new per-substituted p-tert-butylcalix[9]arenes derivatives has been achieved. Functions such as ester, nitrile, or carbonate have been grafted on the phenolic oxygens of calix[9]arene: p-tert-butylcalix[9]arene nona-ethyl acetate, p-tert-butylcalix[9]arene nona-carboxylic acid, p-tert-butylcalix[9]arene nona-cyanopropyloxy, p-tert-butylcalix[9]arene nona-tert-butoxycarbonyle, p-tert-butylcalix[9]arene nona-acetyl, and p-tert-butylcalix[9]arene nona-trifluoroacetyl have been obtained in good yields (from 48% to 78%) and fully characterized. The X-ray structures of p-tert-butylcalix[9]arene nona-tert-butoxycarbonyl and p-tert-butylcalix[9]arene nona-ethyl acetate have been determined. A dynamic NMR study has revealed the high conformational mobility of such structures, even at low temperature. 相似文献
106.
107.
High yield of cationic palladium β-diimine complexes [(CH2(MeCNAr)2)Pd(η3-C4H7)][Y] (Ar = C6H5, Y = PF6 (8); 2-Me-C6H4, Y = PF6 (9); 2,6-Me2-C6H3, Y = PF6 (10); 2,6-iPr2-C6H3, Y = PF6 (11), Y = B(3,5-(CF3)2-C6H3)4 (12)) have been obtained by an oxidative addition of the methallyloxyphosphonium salts (5, 6) to a preformed complex Pd(dba)2 (7) in the presence of the β-iminoamine ligands (1-4).These complexes are thermally stable and have been characterized by 1H and 13C{1H} NMR as well as IR spectroscopy. The structure of the cationic allyl palladium complex (12) has been solved by X-ray crystallography. 相似文献
108.
The crown ethers dibenzo-16-crown-4 and dibenzo-18-crown-5 and a diaryl polyether were complexed by the chromium tricarbonyl group for the purpose of selective functionalization. This complexation did indeed permit exclusive functionalization of the complexed ring. CHO and CH2OH functionalities were introduced ortho to the ether group. It was noted that the nature of the two ether chains had a strong influence on the regioselectivity of the functionalization, which occurred preferentially on the side with the polyether chain. Photochemical decomplexation produced functionalized organic crown ethers. 相似文献
109.
Fatimah Mohammed Alzahrani Norah Salem Alsaiari Khadijah Mohammedsaleh Katubi Abdelfattah Amari Abubakr M. Elkhaleefa Faouzi Ben Rebah Mohamed A. Tahoon 《Molecules (Basel, Switzerland)》2021,26(16)
We report in the present study the in situ formation of magnetic nanoparticles (Fe3O4 or Fe) within porous N-doped carbon (Fe3O4/N@C) via simple impregnation, polymerization, and calcination sequentially. The synthesized nanocomposite structural properties were investigated using different techniques showing its good construction. The formed nanocomposite showed a saturation magnetization (Ms) of 23.0 emu g−1 due to the implanted magnetic nanoparticles and high surface area from the porous N-doped carbon. The nanocomposite was formed as graphite-type layers. The well-synthesized nanocomposite showed a high adsorption affinity toward Pb2+ toxic ions. The nanosorbent showed a maximum adsorption capacity of 250.0 mg/g toward the Pb2+ metallic ions at pH of 5.5, initial Pb2+ concentration of 180.0 mg/L, and room temperature. Due to its superparamagnetic characteristics, an external magnet was used for the fast separation of the nanocomposite. This enabled the study of the nanocomposite reusability toward Pb2+ ions, showing good chemical stability even after six cycles. Subsequently, Fe3O4/N@C nanocomposite was shown to have excellent efficiency for the removal of toxic Pb2+ ions from water. 相似文献
110.
Abderrahmen Guesmi Mohamed Faouzi Zid Ahmed Driss 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):511-512
In the title compound, disodium cobalt tetrakis(dihydrogenphosphate) tetrahydrate, the CoII ion lies on an inversion centre and is octahedrally surrounded by two water molecules and four H2PO4 groups to give a cobalt complex anion of the form [Co(H2PO4)4(OH2)]2?. The three‐dimensional framework results from hydrogen bonding between the anions. The relationship with the structures of Co(H2PO4)2·2H2O and K2CoP4O12·5H2O is discussed. 相似文献