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排序方式: 共有274条查询结果,搜索用时 14 毫秒
91.
Kamil Rahme Julian Oberdisse Dr. Ralf Schweins Dr. Cédric Gaillard Dr. Jean‐Daniel Marty Dr. Christophe Mingotaud Dr. Fabienne Gauffre Dr. 《Chemphyschem》2008,9(15):2230-2236
Hybrid gold–polymer nanoparticles are obtained by self‐assembly of amphiphilic copolymers (Pluronics) in solutions containing preformed gold nanoparticles (diameter ca. 12 nm). Dynamic light scattering, TEM, cryo‐TEM, and small‐angle neutron scattering experiments with contrast variation are used to characterize the structure of the gold–polymer particles. Five Pluronics (F127, F68, F88, F108, P84) with different molecular weights and hydrophilic/hydrophobic balances are investigated. Gold nanoparticles are individually embedded within globules of polymer, even under conditions for which Pluronics micelles do not form in solution. The hybrid particles are several tens of nanometers in size (larger than micelles of the corresponding Pluronics), and the size can be tuned by changing the temperature. 相似文献
92.
Jebors S Fache F Balme S Devoge F Monachino M Cecillon S Coleman AW 《Organic & biomolecular chemistry》2008,6(2):319-329
The synthesis of a series of fully O-derivatised para-acyl-calix[8]arenes is described, where the acyl function is either octanoyl or hexadecanoyl. The groups attached at the phenolic face are, carboxymethoxy (anionic), carboxypropoxy (anionic), 4-sulfonatobutoxy (anionic), ethoxycarboxymethoxy (neutral), ethoxycarboxypropoxy (neutral), 2-methoxyethoxy (neutral) and 2-(2-methoxy)diethoxy (neutral). The use of specific synthetic routes has allowed complete substitution in high yields for all the compounds obtained. The interfacial properties of the compounds have been studied and stable monolayers have been obtained for certain compounds in the series having para-octanoyl substituents; all compounds studied in the series having para-hexadecanoyl substituents formed stable monolayers at the air-water interface. The interactions between O-4-sulfonatobutoxy-para-ocatanoylcalix[8]arene and a series of serum albumins have been studied by dynamic light scattering and specific adsorption of the calix-[8]-arene derivative onto the proteins observed. The anionic derivatives O-4-sulfonatobutoxy-para-ocatanoylcalix[8]arene and O-carboxymethoxy-para-ocatanoylcalix[8]arene have been shown to possess anticoagulant properties but to have no haemolytic toxicity. 相似文献
93.
A tricyclic tetraazatriacetic compound, which is a rigidified derivative of PCTA12 ligand with a cyclohexylene bridge replacing an ethylene one, was prepared. Two synthetic routes have been investigated, both of them implying a common functionalized triamine intermediate. Whatever the route, four synthetic steps were necessary to obtain the target tricyclic ligand. The more effective one (Route B) led to the desired compound in 19% overall yield from the triamine intermediate. The corresponding gadolinium complex of 1/1 stoichiometry was then prepared in order to evaluate it as potential contrast agent for MRI. 相似文献
94.
Isele K Gigon F Williams AF Bernardinelli G Franz P Decurtins S 《Dalton transactions (Cambridge, England : 2003)》2007,(3):332-341
A survey of the crystal structures containing simple {M4O4} cubane units is reported. It shows that the average M-M distance in these complexes is relatively constant for a given metal ion M. The structures are all distorted from the idealised cube to a T(d) structure, and most show a further distortion which, however, usually maintains some elements of symmetry. A system for classifying the different types of ligand in these complexes is proposed. Two new cubanes of cobalt(II) and nickel(II) with the ligand (R,R)-bis-1,2-(1-methylbenzimidazol-2-yl)ethane-1,2-diol, (R,R)- or its enantiomer have been isolated and the crystal structure of the cobalt(II) complex confirms the cubane structure. Electronic, CD and (1)H NMR spectra and magnetic susceptibility data are reported. The magnetic data for these and other compounds in the literature are discussed in terms of the structural parameters. 相似文献
95.
Improved Transversal Relaxivity for Highly Crystalline Nanoparticles of Pure γ‐Fe2O3 Phase 下载免费PDF全文
Dr. Gérald Casterou Vincent Collière Dr. Pierre Lecante Dr. Yannick Coppel Dr. Pierre‐Antoine Eliat Dr. Fabienne Gauffre Dr. Myrtil L. Kahn 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(51):18855-18861
Pure and highly crystalline γ‐Fe2O3 nanocrystals (NCs) are obtained when hydrolysis and oxidation of a FeII organometallic precursor are performed in successive steps. Their synthesis in pure alkylamine leads to NCs of about 6 nm. In aqueous solutions of poly(vinyl)pyrrolidone, such pristine NCs form aggregates of about 150 nm that exhibit a high transversal relaxivity (r2=466 mM ?1 s?1) about four times higher than that of a commercial Feridex magnetic resonance imaging (MRI) contrast agent. Consequently, they provide a significant decrease in the NMR signal at very short echo time (8 ms), which is of paramount importance in clinical practice because of the reduced duration of MRI measurements. 相似文献
96.
Leroy CM Wang HF Fargues A Cardinal T Jubera V Treguer-Delapierre M Boissière C Grosso D Sanchez C Viana B Pellé F 《Physical chemistry chemical physics : PCCP》2011,13(25):11878-11884
Periodic mesoporous Eu(3+) doped titania materials were obtained through the EISA (Evaporation Induced Self Assembly) process. Eu(3+) ions, entrapped within the semi-crystalline walls of the highly porous framework, appear to be advantageous during the probing of surface photochemical reactions. Its emission intensity is very sensitive to the presence of physisorbed molecules, in gas or liquid phase, that reside within the pores. In particular, strong fluctuations in intensity of the (5)D(0)→(7)F(2) transition were observed under UV light exposure on the time scale of tens of seconds. The emission modulation dynamics show a strong correlation with the crystallinity of the titania matrix. Correlation of the emission with the photocatalytic activity of the semiconductor for photodegradation of an organic molecule is observed. A model is proposed to describe the involved mechanisms. 相似文献
97.
Self-assembling mini cell-penetrating peptides enter by both direct translocation and glycosaminoglycan-dependent endocytosis 总被引:1,自引:0,他引:1
Bode SA Thévenin M Bechara C Sagan S Bregant S Lavielle S Chassaing G Burlina F 《Chemical communications (Cambridge, England)》2012,48(57):7179-7181
A small library of cell-penetrating peptides (CPPs) containing a minimized cationic domain and a lipophilic domain of different size was studied. CPPs that could self-assemble were found to enter cells more efficiently, triggering a glycosaminoglycan-dependent pathway. 相似文献
98.
New coumarin derivatives, namely (2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-phenylthiazolidin-3-yl)acetamide, N-(2-(3-methoxyphenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide, 2-(4-methyl-2-oxo-2H-chromen-7-yloxy)-N-(4-oxo-2-(2,3,4trimethoxyphenyl)thiazolidin-3-yl)acetamide and N-(2-(4-bromophenyl)-4-oxothiazolidin-3-yl)-2-(4-methyl-2-oxo-2H-chromen-7-yloxy)acetamide) were synthesized starting from 4-methyl-7-hydroxycoumarin. The structures of the obtained compounds were confirmed by analytical IR and NMR spectra to elucidate the different positions of protons and carbons and as well as theoretical studies (DFT/B3LYP). The new compounds were screened for antibacterial activity. Most of them are more active against E. coli S. aureus and B. subtilis than standard references. 相似文献
99.
Lebon E Bastin S Sutra P Vendier L Piau RE Dixon IM Boggio-Pasqua M Alary F Heully JL Igau A Juris A 《Chemical communications (Cambridge, England)》2012,48(5):741-743
Unexpected room temperature luminescence is observed and rationalized by highly challenging excited state calculations for a functionalized phosphine ligand coordinated on the [Ru(bpy)(tpy)](2+) core. 相似文献
100.
Duygu Ayd?n Tekda?Ufuk Kumru Ay?e Gül GürekMahmut Durmu? Vefa Ahsen Fabienne Dumoulin 《Tetrahedron letters》2012,53(39):5227-5230
A Zn(II) phthalocyanine substituted with eight hydroxylated sulfanyl moieties in non-peripheral positions was designed to exhibit properties desired for photodynamic therapy: hydrophilicity, isomeric purity and near-infrared absorption in addition to high singlet oxygen generation. Photophysical and photochemical studies proved to be promising. 相似文献