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101.
Leite Irena Andrianov Victor Zelencova-Gopejenko Diana Loza Einars Kazhoka-Lapsa Iveta Domracheva Ilona Stojak Marta Chlopicki Stefan Kalvins Ivars 《Chemistry of Heterocyclic Compounds》2021,57(12):1235-1235
Chemistry of Heterocyclic Compounds - 相似文献
102.
Oriana G. Chavez-Pineda Roberto Rodriguez-Moncayo Diana F. Cedillo-Alcantar Pablo E. Guevara-Pantoja Josue U. Amador-Hernandez Jose L. Garcia-Cordero 《Electrophoresis》2022,43(16-17):1667-1700
Biomarkers are relevant indicators of the physiological state of an individual. Although biomarkers can be found in diseased tissue and different biofluids, sampling from blood plasma is relatively easy and less invasive. Among the molecular biomarkers that can be found circulating in plasma are proteins, metabolites, nucleic acids, and exosomes. Some of these plasma-circulating biomarkers are now employed for patient stratification in a broad range of diseases with high sensitivity and specificity and are useful in early diagnosis, initial risk assessment, and therapy selection. However, there is a pressing need to develop novel approaches for biomarker analysis that can be translated into clinical or other settings without complex methodologies or instrumentation. Microfluidics has been touted as a promising technology to carry out this task because it offers high-throughput, automation, multiplexed detection, and portability, possibly overcoming the bottleneck that prevent the translation of novel biomarkers to the point-of-care (POC). Here, we provide a review of the microfluidic systems that have been engineered to detect circulating molecular biomarkers in blood plasma. We also review the different microfluidic approaches for plasma enrichment, which are now being integrated with microfluidic-based biomarker analyzers. Such integration should lead to cost-effective solutions in in vitro diagnostics, with special relevance to POC platforms. 相似文献
103.
Diana Cruz-Garritz Juventino Garcia-Alejandre Hugo Torrens Cecilio Alvarez Raul A. Toscano Rene Poilblanc Alain Thorez 《Transition Metal Chemistry》1991,16(1):130-135
Summary The thiolato-bridged dinuclear compounds [Rh(-SR)-(COD)]2, where R=p-C6HF4 (1),p-C6H4F (2) and CF3 (3), are obtained from the chloro-bridged analogue by ligand exchange.Compound (1) crystallizes in the space group P1 with a=9.740(3)Å, b=11.642(4)Å, c=13.997(6)Å, =103.87(3)°, =106.98(3)° and =105.10(2)°; z=2. In this dinuclear molecule both Rh atoms have a square planar coordination sharing one edge, namely the two sulphur bridging atoms. The Rh—Rh separation of 2.96 Å is consistent with at most a very weak metal-metal interaction. Upon addition of CO the dimeric [Rh(-SR)(CO)2]2 (4), (5) and (6) are obtained, but addition of PPh3 affords the monomeric species [Rh(SR)(PPh3)-(COD)] (7), (8) and (9). Reactions of the dimeric tetracarbonyl derivatives with PPh3 vary with the nature of R; [Rh(-SR)(PPh3)(CO)]2 is obtained when R=p-C6H4F (10) and CF3 (11) but monomeric [Rh(SR)-(PPh3)(CO)2] (12) is produced when R=p-C6HF4. The latter mononuclear compounds, with R=p-C6H4F (13) and CF3 (14), are also formed by reaction of [Rh(SR)-(PPh3)(COD)] with CO. 相似文献
104.
Ella Kh. Kazakova Julia E. Morozova Diana A. Mironova Alexander I. Konovalov 《Journal of inclusion phenomena and macrocyclic chemistry》2012,74(1-4):467-472
Four water-insoluble tetradodecyloxybenzylcalix[4]resorcinarenes with various functional groups at the upper macrocycle rim (unsubstituted calix[4]resorcinarene 1, carboxylic acid derivative 2, ethyl ester derivative 3 and aminoethylamide derivative 4) were synthesized and tested as sorbents for water-soluble azo dyes methyl orange (MO), acid orange 5 (AO 5) and congo red (CR) by solid–liquid extraction method without background electrolyte. It was observed that the sorption of azo dyes reaches 99% for sorbent 4, which is partial protonated in contact with water and becomes able to electrostatic interactions with the dyes. It was demonstrates that calixresorcinarene 4 has the excellent sorption capacity for AO5 (130.5?mg dye per g of sorbent) due to effective calixresorcinarene—dye association in equal molar ratio mode. 相似文献
105.
Rogelio P. Frutos Isabelle Gallou Diana Reeves Yibo Xu Dhileepkumar Krishnamurthy Chris H. Senanayake 《Tetrahedron letters》2005,46(48):8369-8372
Expedient and practical new methodology for the synthesis of substituted imidazoles was developed to provide a rapid access to a variety of 2-substituted, 1,2-disubstituted and 1,2,4-trisubstituted imidazoles by the direct CuCl-mediated reaction of nitriles with α-amino acetals in an intermolecular as well as intramolecular fashion. 相似文献
106.
Anh N. Hong Diana Luong Mohammed Alghamdi Wei-Cheng Liao Weiyi Zhang Emily Kusumoputro Yichong Chen Prof. P. Alex Greaney Prof. Yongtao Cui Prof. Jing Shi Prof. Xianhui Bu Prof. Boniface P. T. Fokwa Prof. Pingyun Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(52):e202201576
Two new rod-packing metal–organic frameworks (RPMOF) are constructed by regulating the in situ formation of the capping agent. In CPM-s7, carboxylate linkers extend 1D manganese-oxide chains in four additional directions, forming 3D RPMOF. The substitution of Mn2+ with a stronger Lewis acidic Co2+, leads to an acceleration of the hydrolysis-prone sulfonate linker, resulting in presence of sulfate ions to reduce two out of the four carboxylate-extending directions, and thus forming a new 2D rod-packing CPM-s8. Density functional theory calculations and magnetization measurements reveal ferrimagnetic ordering of CPM-s8, signifying the potential of exploring 2D RPMOF for effective low-dimensional magnetic materials. 相似文献
107.
Educators involved in the current reform movement in mathematics education recommend that students be actively involved in constructing their own knowledge and developing powerful mathematical concepts. This study suggests how ideas based on constructivist learning theory can be put into practice in a preservice mathematics education class. 相似文献
108.
López D Buitrago R Sepúlveda-Escribano A Rodríguez-Reinoso F Mondragón F 《Langmuir : the ACS journal of surfaces and colloids》2007,23(24):12131-12137
The catalytic adsorption of NO on activated carbon materials provides an appropriated alternative for the control of low-concentration emissions of this air pollutant. The surface complexes formed upon NO adsorption at 30 degrees C were studied by X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD). The effects of the addition of O2 and the presence of copper as a catalyst were studied. Copper assisted the oxygen transfer to the carbon matrix. For the Cu-impregnated carbon sample, the presence of O2 favored NO adsorption by increasing the breakthrough time, the adsorption capacity, and the formation of nitrogen and oxygen complexes of higher thermal stabilities, which mainly desorbed as NO and CO2. 相似文献
109.
Alexandru MG Visinescu D Madalan AM Lloret F Julve M Andruh M 《Inorganic chemistry》2012,51(9):4906-4908
The first 3d-4f-5d heterotrimetallic complexes using [W(V)(bipy)(CN)(6)](-) as a metalloligand were synthesized (bipy = 2,2'-bipyridine). The structural and magnetic properties of three [Cu(II)Ln(III)W(V)] complexes (Ln = Gd, Ho, Tb) are discussed. 相似文献
110.
Daniele Aiello Hendrik Jonas Anna Carbone Daniela Carbone Camilla Pecoraro Luisa Tesoriere Jens Khler Bernhard Wünsch Patrizia Diana 《Molecules (Basel, Switzerland)》2022,27(21)
Natural products are an excellent source of inspiration for the development of new drugs. Among them, betalains have been extensively studied for their antioxidant properties and potential application as natural food dyes. Herein, we describe the seven-step synthesis of new betalamic acid analogs without carboxy groups in the 2- and 6-position with an overall yield of ~70%. The Folin–Ciocalteu assay was used to determine the antioxidant properties of protected intermediate 21. Additionally, the five-step synthesis of betalamic acid analog 35 with three ester moieties was performed. Using NMR techniques, the stability of the obtained compounds towards oxygen was analyzed. 相似文献