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81.
《Journal of Coordination Chemistry》2012,65(16):2912-2922
Two d10 metal coordination polymers, [Zn(µ-Me2biim)Cl2] n (1) and [Cd3(MeHbiim)2(1,4-BDC)3] n (2) (Me2biim?=?N,N′-dimethyl-2,2′-biimidazole, MeHbiim?=?N-methyl-2,2′-biimidazole, 1,4-BDC?=?1,4-benzenedicarboxylate), were synthesized under hydrothermal conditions and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single-crystal X-ray crystallography. Complex 1 features an infinite neutral zigzag 1-D chain. Interchain hydrogen-bonding interactions further extend the 1-D arrangement to generate a 2-D supramolecular architecture. Complex 2 features a 3-D coordination polymer with α-Po net topology, based on linear trinuclear {Cd3O14N4} clusters. Both complexes have high thermal stability and exhibit strong luminescence at room temperature. 相似文献
82.
Exhaled breath condensate is a promising, non-invasive, diagnostic sample obtained by condensation of exhaled breath. Starting from a historical perspective of early attempts of breath testing towards the contemporary state-of-the-art breath analysis, this review article focuses mainly on the progress in determination of non-volatile compounds in exhaled breath condensate. The mechanisms by which the aerosols/droplets of non-volatile compounds are formed in the airways are discussed with methodological consequences for sampling. Dilution of respiratory droplets is a major problem for correct clinical interpretation of the measured data and there is an urgent need for standardization of EBC. This applies also for collection instrumentation and therefore various commercial and in-house built devices are described and compared with regard to their design, function and collection parameters. The analytical techniques and methods for determination of non-volatile compounds as potential markers of oxidative stress and lung inflammation are scrutinized with an emphasis on method suitability, sensitivity and appropriateness. The relevance of clinical findings for each group of possible non-volatile markers of selected pulmonary diseases and methodological recommendations with emphasis on interdisciplinary collaboration that is essential for future development into a fully validated clinical diagnostic tool are given. 相似文献
83.
《Journal of Coordination Chemistry》2012,65(22):4102-4116
The tetra α- or β-thiophene substituted metal and metal-free phthalocyanines (Pcs) M[Pc(α-OCH2Thiopen)4] and M[Pc(β-OCH2Thiopen)4] {(α-ThMet-MPc), (β-ThMet-MPc) [ThMet: Thiophene methoxy], M = Zn(II), Co(II) and, 2H} were synthesized from the corresponding 3’-(thiophen-3-ylmethoxy)phthalonitrile or 4’-(thiophen-3-ylmethoxy)phthalonitrile (ThMePN). The structural characterization, spectral, and antioxidant properties of a series of new Pcs were also presented. Both α- and β-substituted Pc complexes increased solubility in polar solvents, such as THF, DMF, and DMSO. FT-IR, 1H-NMR, 13C-NMR, UV–vis, MALDI-TOF/MS spectral, and elemental analysis data were used to characterize the compounds. The aggregation behaviors of 3–8 were also investigated at different concentrations in THF. Antioxidant test methods, α,α-diphenyl-β-picrylhydrazyl radical scavenging activity, metal chelating activity, and reducing power, were used to determine the antioxidant activities. 6 showed very good ferrous ion chelating activity of 81 ± 1%. 6, 5, 4, and 3 showed better reducing power than trolox, ascorbic, acid and butylated hydroxytoluene, commercially used antioxidants. 相似文献
84.
《Tetrahedron》2019,75(43):130624
An Fe(III)-catalyzed efficient method has been developed for the synthesis of selenoester derivatives in high yields through the coupling of α-amino carbonyl/glycine derivatives and diselenides under ambient air. A library of benzoselenoate derivatives having a variety of substituents has been synthesized. A plausible reaction pathway has been predicted. Experimental results suggest that the reaction proceeds through a radical pathway. Operational simplicity, compatibility with various α-amino carbonyls and diselenides, high yields, fast reaction and mild reaction conditions are the notable advantages of this procedure. We have also shown the practical application of the synthesized selenoesters which is useful to generate peptide bonds in biological sciences. 相似文献
85.
Tejal Barkhade Ambadas Phatangare Shailendra Dahiwale Santosh Kumar Mahapatra Indrani Banerjee 《Surface and interface analysis : SIA》2019,51(9):894-905
The advent of nano-biotechnology has inspired the interface interaction study between engineered nanoparticles (NPs) and biomolecules. The interaction between Fe content titanium dioxide (TiO2) NPs and adenosine triphosphate (ATP) biomolecules has been envisioned. The effect of Fe content in TiO2 matrix was studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The increase in Fe content caused a decrease in particle size with change in morphology from spherical to one-dimensional rod structure. The Fe incorporation in the TiO2 matrix reduced the transition temperature from anatase to rutile (A-R) phase along with formation of haematite phase of iron oxide at 400°C. The interaction of Fe content TiO2 NPs with ATP molecule has been studied using spectroscopic method of Raman scattering and infrared vibration spectrum along with TEM. Fe content in TiO2 has enhanced the interaction efficiency of the NPs with ATP biomolecules. Raman spectroscopy confirms that the NPs interact strongly with nitrogen (N7) site in the adenine ring of ATP biomolecule. Engineering of Fe content TiO2 NP could successfully tune the coordination between metal oxide NPs with biomolecules, which could help in designing devices for biomedical applications. 相似文献
86.
Yakun Wang Qinghe Gao Nan Li Yifan Chen Jingwen Cui Feiyu Gao Qingwei Meng 《Tetrahedron》2018,74(30):4126-4133
A facile and efficient protocol for α-benzoyloxylation and α-hydroxylation of β-keto amides by phase-transfer catalysis is presented. This methodology provides mild and practical access to a variety ofα-oxygenated β-keto amides. Furthermore, α-benzoyloxylation products can be easily converted into α-hydroxylation compounds, which are useful synthetic precursors of biological targets. 相似文献
87.
Phthalimide derivatives as nitrogen nucleophiles with α,β‐unsaturated aldehydes for asymmetric aza‐Michael additions have been reported. The reactions proceed smoothly to afford corresponding Michael adducts in good yields (up to 98%) and enantioselectivities (up to 95% ee). 相似文献
88.
Samia Guezane Lakoud Malika Berredjem Nour-Eddine Aouf 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):762-768
Abstract A new series of modified α-amidophosphonates (or β-ketophosphonate) was synthesized by an efficient method, starting from aminoesters and chloroacetyl chloride. We have established that chloroacetyl chloride is a suitable reagent allowing the introduction a halogen moiety for the Arbuzov reaction. The α-amidophosphonates were prepared in two steps (acetylation, phosphorylation). Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
89.
Mohamed Abass Hassan A. Allimony Heba Hassan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1799-1810
Abstract Oxidation of 3-acetyl-1-alkyl-4-hydroxyquinolin-2(1H)-ones using selenium dioxide under Riley conditions was described. The oxidation reaction produced a mixture of 2 unexpected α-keto acid and its dehydrated dimer derivatives. The oxidation reaction was studied under different reaction conditions in order to maximize the yields and optimize reaction conditions. Also, 1-alkyl-4-hydroxy-3-(2-nitroacetyl)quinolin-2(1H)-one and/or 3-acetyl-1-alkyl-4-diflouro-boryloxyquinolin-2(1H)-one derivatives were subjected to the same oxidation reaction giving rise improved reaction yields and selectivity in case of the boron-complex. Alkaline degradation of the dehydrated dimers led to formation of the 4-hydroxy-2-oxoquinoline-3-carboxylic acids while under the same conditions the α-keto acids underwent deoxalylation. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures]. 相似文献
90.
《Tetrahedron》2019,75(28):3856-3863
Without employing any transition metal, organic solvent and base, a facile, economical and environmentally friendly strategy has been developed for the α-hydroxylation of β-keto esters and β-keto amides with peroxides via radical cross-coupling reaction in water under open-air conditions. This protocol allows a convenient access to various α-hydroxy-β-keto esters and α-hydroxy-β-keto amides with up to 92% yield (34 examples). Moreover, the reaction was successfully scaled up to gram quantity and mechanistic studies showed the radical pathway was involved in this hydroxylation. 相似文献