3017-53-6Relevant articles and documents
Interface-controlled calcium phosphate mineralization: effect of oligo(aspartic acid)-rich interfaces
Hentrich, Doreen,Junginger, Mathias,Bruns, Michael,B?rner, Hans G.,Brandt, Jessica,Brezesinski, Gerald,Taubert, Andreas
, p. 6901 - 6913 (2015)
The phase behavior of an amphiphilic block copolymer based on a poly(aspartic acid) hydrophilic block and a poly(n-butyl acrylate) hydrophobic block was investigated at the air-water and air-buffer interface. The polymer forms stable monomolecular films on both subphases. At low pH, the isotherms exhibit a plateau. Compression-expansion experiments and infrared reflection absorption spectroscopy suggest that the plateau is likely due to the formation of polymer bi- or multilayers. At high pH the films remain intact upon compression and no multilayer formation is observed. Furthermore, the mineralization of calcium phosphate beneath the monolayer was studied at different pH. The pH of the subphase and thus the polymer charge strongly affects the phase behavior of the film and the mineral formation. After 4 h of mineralization at low pH, atomic force microscopy shows smooth mineral films with a low roughness. With increasing pH the mineral films become inhomogeneous and the roughness increases. Transmission electron microscopy confirms this: at low pH a few small but uniform particles form whereas particles grown at higher pH are larger and highly agglomerated. Energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy confirm the formation of calcium phosphate. The levels of mineralization are higher in samples grown at high pH.
Construction of a smart glutathione peroxidase mimic with temperature responsive activity based on block copolymer
Yin, Yanzhen,Wang, Liang,Jin, Haiyan,Lv, Chunyan,Yu, Shuangjiang,Huang, Xin,Luo, Quan,Xu, Jiayun,Liu, Junqiu
, p. 2521 - 2529 (2011)
To construct a smart artificial antioxidative enzyme on a nano-scaffold, a novel method for designing glutathione peroxidase (GPx) active sites on block copolymer vesicles was developed by simple blending predesigned temperature-sensitive block copolymers with the main catalytic units of GPx. A series of functional block copolymers, poly(N-isopropylacrylamide)-b- polyacrylamides loaded with recognition and catalytic sites, were synthesized via ATRP and click chemistry. Through altering the molar ratio of the functional copolymers, the optimum GPx mimic based on copolymer vesicles was obtained by self-assembly of temperature-sensitive block copolymers through a blending process. Significantly, the catalytic activity of the optimum GPx mimic can be well modulated by changing the temperature. It was proved that the change in self-assembly structure of the block copolymer played an important role in the modulation of the catalytic activity. This method not only bodes well for designing smart antioxidative enzyme mimics that could be used in cosmetics as antioxidative additives but also highlights the construction of other regulatory biologically related functional biomaterials.
BENZIMIDAZOLE DERIVATIVES
-
Page/Page column 53; 66, (2021/06/26)
The invention relates to benzimidazoles of Formula (I) and pharmaceutically acceptable salts thereof, wherein R1 to R6 are as defined in the description; to their use in medicine; to compositions containing them; to processes for their preparation; and to intermediates used in such processes. The benzimidazoles of Formula (I) are ITK inhibitors and are therefore potentially useful in the treatment of a wide range of disorders including, atopic dermatitis.
Enantioselective Synthesis of N-Benzylic Heterocycles: A Nickel and Photoredox Dual Catalysis Approach
Pezzetta, Cristofer,Bonifazi, Davide,Davidson, Robert W. M.
supporting information, p. 8957 - 8961 (2019/11/11)
Reported herein is a dual nickel- and photoredox-catalyzed modular approach for the preparation of enantioenriched N-benzylic heterocycles. α-Heterocyclic carboxylic acids, easily obtainable from common commercial material, are reported as suitable substrates for a decarboxylative strategy in conjunction with a chiral pyridine-oxazoline (PyOx) ligand, providing quick access to enantioenriched drug-like products. The presence of a directing group on the heterocyclic moiety is shown to be beneficial, affording improved stereoselectivity in a number of cases.
