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91.
Nabil El Brahmi Saïd El Kazzouli Serge Mignani Régis Laurent Sonia Ladeira Anne-Marie Caminade Mosto Bousmina Jean-Pierre Majoral 《Tetrahedron》2017,73(10):1331-1341
Phosphorus-containing dendrimers are attractive carriers for the delivery of bioactive molecules due to their very particular architecture, globular shape and chemical and physical properties. Herein we report a simple synthetic approach of ethacrynic acid derivatives loaded-phosphorus dendrimers by symmetrical grafting of ethacrynic acid analogues by nucleophilic substitution of each chlorine of P(S)Cl2 end groups. We report also for the first time an unsymmetrical grafting of two different phenol derivatives by a selective substitution of one chlorine of P(S)Cl2 end group followed by the grafting of the second phenol. 相似文献
92.
The shape parameter obtained from the geometric model of Ishihara and Hayashida for ovaloid polymers, together with the scaled-particle theory, are applied to a mixture of methane and ethylene. The results are in good agreement with the experimental values, indicating the validity of the model and suggesting application to other polymer properties. 相似文献
93.
Dr. Aude Sourdon Dr. Magali Gary-Bobo Dr. Marie Maynadier Dr. Marcel Garcia Dr. Jean-Pierre Majoral Dr. Anne-Marie Caminade Dr. Olivier Mongin Dr. Mireille Blanchard-Desce 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(14):3637-3649
The synthesis and the photophysical properties of a new class of fully organic monodisperse nanoparticles for combined two-photon imaging and photodynamic therapy are described. The design of such nanoparticles is based on the covalent immobilization of a dedicated quadrupolar dye that combines excellent two-photon absorbing (2PA) properties, fluorescence and singlet oxygen generation ability, in a phosphorous-based dendrimeric architecture. First, a bifunctional quadrupolar dye bearing two different grafting moieties, a phenol function and an aldehyde function, was synthesized. It was then covalently grafted through its phenol function to a phosphorus-based dendrimer scaffold of generation 1. The remaining aldehyde functions were then used to continue the dendrimer synthesis up to generation 2, introducing finally 24 water-solubilizing triethyleneglycol chains at its periphery. A dendrimer confining 12 photoactive quadrupolar units in its inner scaffold and showing water solubility was thus obtained. Interestingly, the G1 and G2 dendrimers retain some fluorescence as well as significant singlet oxygen production efficiencies while they were found to show very high 2PA cross-sections in a broad range of the NIR biological spectral window. Hydrophilic dendrimer G2 was tested in vitro on breast cancer cells, first in one- and two-photon microscopy, which allowed for visualization of their cell internalization, then in two-photon photodynamic therapy. While being nontoxic in the dark and, more importantly, under exposure to daylight, dendrimer G2 proved to be a very efficient cell-death inducer only under two-photon irradiation in the NIR. 相似文献
94.
The nonsphericity parameter γrelated to the Isihara shape factor for ovaloid polymers f by the relation f = (γ/4) + (1/4) is calculated through an expansion of the radius of the molecule in spherical harmonics. The limitations of the method when applied to polymers with high f are discussed. 相似文献
95.
96.
Christopher J. Cramer Anne‐Marie Kelterer Alfred D. French 《Journal of computational chemistry》2001,22(11):1194-1204
Rotational coordinates about the C(3)–O(4) bonds of 2,4‐dioxaheptane (DOH) and 2,4,6‐trioxaheptane (TOH) are compared at correlated levels of electronic structure theory for gauche and trans orientations of the O(2)–C(3) bonds. TOH has overlapping anomeric effects, while DOH does not. The overlapping stereoelectronic effect shows its largest impact on the length of the O(2)–C(3) bond, which is typically 0.02 Å longer in DOH than in TOH. However, the energetic consequences of the overlapping anomeric effect in TOH are very small, as judged by total conformational energies and analysis of delocalization energies within a natural bond orbital framework. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1194–1204, 2001 相似文献
97.
Anne-Marie Chollet-Gravey Liliane Vo-Quang Yen Vo-Quang Francois Le Goffic 《合成通讯》2013,43(18-19):1847-1858
A novel procedure for the preparation of the phosphonic analogue of homoserine is described starting from the commercially available 4-acetoxy-azetidin-2-one. 相似文献
98.
Thomas Lainer Dr. Deepak Dange Michael Pillinger Prof. Dr. Roland C. Fischer Prof. Dr. Anne-Marie Kelterer Prof. Dr. Cameron Jones Dr. Michael Haas 《ChemistryOpen》2022,11(3):e202100240
A convenient metal-free approach towards an N-heterocyclic carbene (NHC)-coordinated disilene 2 is described. Compound 2 , featuring the disilene incorporated in cyclopolysilane framework, was obtained in good yield and characterized using NMR spectroscopy and X-ray crystallography. Density functional theory (DFT) calculations of the reaction mechanism provide a rationale for the observed reactivity and give detailed information on the bonding situation of the base-stabilized disilene. Compound 2 undergoes thermal or light- induced (λ=456 nm) NHC loss, and a dimerization process to give a corresponding dimer with a Si10 skeleton. In order to shed light on the dimerization mechanism, DFT calculations were performed. Moreover, the reactivity of 2 was examined with selected examples of transition metal carbonyl compounds. 相似文献
99.
Raya J Hirschinger J Ovarlez S Giulieri F Chaze AM Delamare F 《Physical chemistry chemical physics : PCCP》2010,12(43):14508-14514
Despite the numerous studies of the famous indigo-based pigment Maya Blue, there are still many questions regarding the elucidation of its structure. Here, two-dimensional (2D) (1)H-(29)Si heteronuclear correlation (HETCOR) spectroscopy with frequency-switched Lee-Goldburg (FSLG) homonuclear decoupling is applied to sepiolite and sepiolite-indigo complexes. Owing to the high resolution in the (1)H dimension of the 2D (1)H-(29)Si HETCOR spectrum obtained by FSLG homonuclear decoupling, the assignment of the (29)Si cross-polarization magic-angle spinning (CPMAS) spectrum of sepiolite is clearly confirmed. Moreover, 2D (1)H-(29)Si FSLG-HETCOR spectroscopy gives the first direct evidence that some indigo molecules are inserted in the sepiolite structure whereas no interaction between indigo and the external side surface (silanol groups) is observed in the (29)Si CPMAS spectra. These results are consistent with the fact that indigo molecules interact with water coordinated to magnesium and suggest that Maya Blue made from sepiolite is not a surface complex. 相似文献
100.
We report on the investigation of thermal effects in high-repetition-rate pulsed optical parametric oscillators emitting in the mid-IR. We find that the thermal load induced by the nonresonant idler absorption plays a critical role in the emergence of thermally induced bistability. We then demonstrate a significant improvement of the conversion efficiency (more than 30%) when a proper axial temperature gradient is applied to the nonlinear crystal by use of a two-zone temperature-controlled oven. 相似文献