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661.
Dr. Christiane E. I. Knappke Dr. Sabine Grupe Dominik Gärtner Martin Corpet Dr. Corinne Gosmini Prof. Dr. Axel Jacobi von Wangelin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):6828-6842
Reductive cross‐electrophile coupling reactions have recently been developed to a versatile and sustainable synthetic tool for selective C?C bond formation. The employment of cheap and abundant electrophiles avoids the pre‐formation and handling of organometallic reagents. In situ reductive coupling is effected in the presence of a transition‐metal catalyst (Ni, Co, Pd, Fe) and a suitable metallic reductant (Mn, Zn, Mg). This Concept article assesses the current state of the art and summarizes recent protocols with various combinations of alkyl, alkenyl, allyl, and aryl reagents and highlights key mechanistic studies. 相似文献
662.
Michele Cezimbra Perim Joelma da Costa Borges Eulália Maria Lima da Silva Thiago Antônio de Sousa Araújo Ana Carolina Oliveira da Silva Valéria Christiane da Silva 《Natural product research》2019,33(16):2383-2388
This study reported the antimicrobial activity of the bark extract of Davilla nitida on multidrug resistant bacteria isolated from Diabetic Foot Infections. Antibacterial activity of the bark extract was evaluated by agar Disk-Diffusion (DD), Broth Dilution (BD), Checkerboard and Time-kill methods. The extract showed a significant antibacterial activity against all groups of bacteria tested. BD was more sensitive for determining the antibacterial activity of the bark extract than the DD method. The bark extract inhibited the growth of bacteria with high-levels of antibiotic-resistance, such as Pseudomonas spp. (100.0%), Enterobacer spp. (88.89%), Staphylococcus aureus (54.55%), Streptococcus pneumoniae (75.0%), Staphylococcus saprophyticus (92.86%). The combination of extract with antibiotics resulted in an additive effect against most of the strains tested. Time-kill kinetics profiles of bark extract showed bactericidal and time-dependent properties. Our results suggest that the bark extract of Davilla nitida is a source of bioactive compounds, which may be useful against antibiotic-resistant bacteria. 相似文献
663.
The complex formation of uranyl UO(2)(2+) with chloride ions in acetonitrile was studied by UV-vis and U L(III) EXAFS spectroscopy. The investigations unambiguously point to the existence of a [UO(2)Cl(4)](2-) species in solution with D(4)(h)() symmetry. The distances in the U(VI) coordination sphere are U-O(ax) = 1.77 +/- 0.01 Angstroms and U-Cl = 2.68 +/- 0.01 Angstroms. 相似文献
664.
Pascale Léon Christiane Garbay-Jaureguiberry Jean-Bernard Le Pecq Bernard P. Roques 《Tetrahedron letters》1985,26(40):4929-4932
The 6-ethyl-10-methoxy-7H-pyrido[4,3-c ]carbazole is synthesized via a novel and convenient method involving the condensation of the 2-lithio-5-methoxyindole with the appropriate alkyl pyridyl ketone. Quaternarization of this compound by means of a rigid bis(ethyl-piperidyl) linking chain leads to a new potential antitumour dimer. 相似文献
665.
The holographic techniques are applied to the kinetic study of a photopolymerization reaction under steady state illumination. A theoretical approach of this problem is introduced which allows the intrinsic initiating activity of several amine-derived radicals to be determined. 相似文献
666.
667.
Ansgar Stratmann Thomas Schupp Christiane Toupet Wolfgang Schilling Lukas Oberer Rene Traber 《ChemInform》2002,33(41):222-222
668.
Raimund Ziegler Dr. Markus Seibald Dr. Christiane Stoll Prof. Dr. Hubert Huppertz 《欧洲无机化学杂志》2023,26(20):e202300174
The new zinc borate Zn3B4O9 was synthesized at high-pressure/high-temperature conditions of 10 GPa and 1173 K in a Walker-type multianvil pressure device. It crystallizes in the space group P (no. 2) with a=5.5028(2) Å, b=6.7150(3) Å, c=7.8887(3) Å, α=83.99(1)°, β=73.38(1)°, γ=74.75(1)°, V=269.35(2) Å3, and two formula units (Z=2) per unit cell. The structure was confirmed via single-crystal X-ray diffraction. Zn3B4O9 can be synthesized phase pure, which is shown with a Rietveld refinement. IR-spectroscopic data of a powder sample were collected. 相似文献
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670.