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.
Synthesis of poly(methyl methacrylate)-S/oc/c-poly(l-histidine) and its use as a hybrid silver nanoparticle conjugate
Shin, Nam Ho,Lee, Jin Kyu,Li, Haiqing,Ha, Chang-Sik,Shchipunov, Yury A.,Kim
, p. 6948 - 6953 (2010)
Poly[(methyl methacrylate)-block-poly(L-histidine)] (PMMA-b-PHIS) was synthesized by combining atom transfer radical polymerization and living ring-opening polymerization of α-amino acid-N- carboxyanhydride. The resulting hybrid block copolymer forms reverse micelles in the mixture solution of water and N,N-dimethylformamide (DMF) and self-assembles into PHIS/PMMA core/shell spheres with controllable size in the range of 80 to 250 nm depending on the micellization temperature. The self-assembly of PMMA-b-PHIS was carried out in H20/DMF (3/7) mixture in the presence of AgN03. Reduction of the resulting Ag ions encapsulated inside of the reverse micelles yielded an attractive Ag nanoparticle core/polymer shell conjugate system. Copyright
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.
Regioselective 2-alkylation of indoles with α-bromo esters catalyzed by Pd/P,P=O system
Tian, Wei,Li, Bowen,Tian, Duanshuai,Tang, Wenjun
supporting information, p. 197 - 200 (2021/08/13)
A palladium-catalyzed 2-alkylation of indoles with α-bromo esters is developed by employing a P,P=O ligand. The method features excellent regioselectivities, mild reaction conditions, and good functional group compatibility. The employment of the P,P=O ligand as well as 4? molecular sieves were crucial for the success of the transformation. Mechanistic studies indicate the reaction proceed through a radical pathway.
BENZIMIDAZOLE DERIVATIVES
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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.
Pyridine oxygen radical suo ester derivative and its preparation method, herbicidal composition and application (by machine translation)
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Paragraph 0146-0148, (2019/04/10)
The invention belongs to the technical field of agricultural chemicals, in particular to a pyridine oxygen radical suo ester derivative and its preparation method, herbicidal composition and application. The pyridine oxygen radical suo acid ester derivative shown in formula I, Wherein A, B are respectively independently represents halogen, contain or not contain halogen alkyl or cycloalkyl; C represents hydrogen, halogen, alkyl, haloalkyl; Q represents halogen, cyano, cyano alkyl, hydroxy alkyl, amino, nitro, formyl, not containing or halogen-containing alkyl group or the like; the representative of M - alkyl - R, R represents an unsubstituted or substituted heterocyclic radical, aryl, heteroaryl; Y represents O or S; X represents a nitryl or NR1 R2 . The herbicidal activity is excellent, and have higher crop safety, especially for rice, soybean key crops has established a good selectivity. (by machine translation)
PROTECTED ORGANOBORONIC ACIDS WITH TUNABLE REACTIVITY, AND METHODS OF USE THEREOF
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Page/Page column 45, (2017/03/08)
Disclosed are a range of protected organoboronic acid reagents useful in the modular assembly of complex organic compounds. The reactivities of the protected organoboronic acid reagents may be varied predictably by changes to the number and identities of their substituents. Also disclosed are methods of using the protected organoboronic acid reagents in the synthesis of organic compounds.
INHIBITORS OF HUMAN IMMUNODEFICIENCY VIRUS REPLICATION
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Page/Page column 91, (2016/11/17)
Compounds of Formulas I-VI, including pharmaceutically acceptable salts thereof, and compositions and methods for treating human immunodeficiency virus (HIV) infection are set forth. Formula I is exemplified below: Formula (i)
Enantioselective synthesis of quaternary α-amino acids via l -tert-leucine-derived squaramide-catalyzed conjugate addition of α-nitrocarboxylates to enones
Bera, Kalisankar,Satam, Nishikant S.,Namboothiri, Irishi N. N.
, p. 5670 - 5680 (2016/07/14)
Enantioselective Michael addition of tertiary α-nitroesters to β-unsubstituted vinyl ketones has been carried out in the presence of an l-tert-leucine-derived squaramide as organocatalyst. The products, quaternary α-nitroesters, were formed in excellent yield and moderate to good ee's in most cases. Scale-up of the reaction and synthetic applications of the products, including transformation to representative quaternary α-amino acids, have also been demonstrated.