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121.
Vandana Tripathi Lagy T Baby PV Madhusudhana Rao SK Hui R Singh JJ Das P Sugathan N Madhavan AK Sinha 《Pramana》1999,53(3):535-539
The ground state and excited state transfer yields for the 2-neutron pickup channel in the 28Si+68Zn system have been measured explicitly. The recoil mass separator at the nuclear Science Centre, New Delhi was used for the
measurement. A NaI(T1) detector was used for detecting the deexcitation γ’s from the transfer products. The kinematic coincidence technique was employed for the transfer measurement. Simplified coupled
channels calculations show that out of all transfer channels the major contribution to the sub-barrier enhancement comes from
the ground state 2 neutron pickup channel with a ground state Q-value of+1.83 MeV. 相似文献
122.
Conjugated, borole-linked polymers have been self-assembled based on boronate ester formation between a fluorene-2,7-diboronic acid and 1,2,4,5-tetrahydroxybenzene. Readily soluble polymers with molecular weights approaching 60 000 have been generated with materials exhibiting extended conjugation over approximately 3-5 borole linkages. Emission from these polymers reaches into the visible (blue) range, representing a novel class of blue-emitting materials. 相似文献
123.
124.
Guy Lavigne Noël Lugan Soa Rivomanana Faizel Mulla Jean-Marc Soulié Philippe Kalck 《Journal of Cluster Science》1993,4(1):49-58
An attempt to establish a link between the rich chemistry of ruthenium carbonyl clusters doped by nucleophilic anions, and the known effect of promoters in some ruthenium-based catalytic processes. 相似文献
125.
Noël Lugan Jean -Michel Savariault Guy Lavigne Jean -Jacques Bonnet 《Journal of chemical crystallography》1983,13(6):389-405
The title compound is (μ-H)Ru3(CO)7(μ-As(C6H5)CH2As(C6H5)2)((C6H5)2 AsCH2As(C6H5)2)·CH2C12. Crystal data: monoclinic,P21/n, cell parameters (X-ray)a=12.82(2) Å,b=22.91(2) Å,c=17.83(2) Å, β=99.1(3)°; (neutron)a=12.94(1) Å, β=22.95(2)Å,c=17.93(3)Å,β=99.55(5)°. The structure was solved from X-ray data. FinalR indices areR(F)=0.051,R w (F)=0.049 (X-ray);R(F)=0.064,R w (F)=0.048,R(F 2)=0.072,R w (F2)=0.088 (neutron). The complex is derived from Ru3(CO)8(dpam)2 through reaction with hydrogen. The structure consists of a triangular array of metal atoms involving three metal-metal bonds[Ru(1)?Ru(2)=2.912(7)Å;Ru(1)?Ru(3)=2.829(3) A; Ru(2)?Ru(3)=2.845(6) Å]. The metal-metal edge Ru(1)?Ru(2) is supported by a bridging bis(diphenylarsino)methane ligand which lies in the equatorial plane. Activation of the second dpam ligand has generated the new face-bridging ligand unit μ-As(C6H5)CH2As(C6H5)2. In this unit, the bridgehead As atom spans over the Ru(1)?Ru(2) bond, while the second As atom is only bonded to Ru(3). The metal environment is achieved by CO ligands. The hydride ligand is bridging the Ru(1)?Ru(2) vector [Ru(1)?H=1.791(10) Å; Ru(2)?H=1.818(8) Å]. Geometric features of the dibridged Ru(μ-H)(μ-As)Ru bond are discussed. 相似文献
126.
Dmitry A. Valyaev Oleg V. Semeikin Nikolai A. Ustynyuk Alix Sournia-Saquet Guy Lavigne 《Journal of organometallic chemistry》2007,692(15):3207-3211
The present paper reports the unprecedented observation of a catalytic electrochemical proton reduction based on metallocumulene complexes. Manganese phenylvinylidene (η5-C5H5)(CO)(PPh3)MnCC(H)Ph (1) and diphenylallenylidene (η5-C5H5)(CO)2MnCCCPh2 (3) are shown to catalyze the reduction of protons from HBF4 into dihydrogen in CH2Cl2 or CH3CN media at −1.60 and −0.84 V (in CH3CN) vs. Fc, respectively. The working potential for 3 (−0.84 V vs. Fc in CH3CN) is the lowest reported to date for protonic acids reduction in non-aqueous media. The similar catalytic cycles disclosed here include the protonation of 1, 3 into the carbyne cations [(η5-C5H5)(CO)(PPh3)MnC-CH2Ph]BF4 ([2]BF4), [(η5-C5H5)(CO)2MnC-CHCPh2]BF4 ([4]BF4) followed by their reduction to the corresponding 19-electron radicals 2, 4, respectively. Both carbyne radicals undergo a rapid homolytic cleavage of the Cβ-H bond generating an H-radical producing molecular hydrogen with concomitant recovery of the neutral metallocumulenes thereby completing a catalytic cycle. 相似文献
127.
A Direct,Modular, and Efficient Construction of the PCP Structural Motif through Coupling of Manganese Carbyne Complexes with Phosphines 下载免费PDF全文
Dr. Dmitry A. Valyaev Stéphanie Bastin Kamil I. Utegenov Noël Lugan Guy Lavigne Prof. Dr. Nikolai A. Ustynyuk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(8):2175-2178
Easily available carbyne complexes of manganese were used as a source of carbyne fragments in an unconventional synthesis of backbone‐substituted diphosphinomethanes and cyclic P‐ylides upon coupling with secondary or tertiary phosphines, respectively, followed by demetalation under mild conditions. 相似文献
128.
Dr. Christopher D. Fage Dr. Thomas Lathouwers Michiel Vanmeert Dr. Ling-Jie Gao Dr. Kristof Vrancken Eveline-Marie Lammens Angus N. M. Weir Ruben Degroote Prof. Harry Cuppens Dr. Simone Kosol Prof. Thomas J. Simpson Prof. Matthew P. Crump Prof. Christine L. Willis Prof. Piet Herdewijn Prof. Eveline Lescrinier Prof. Rob Lavigne Prof. Jozef Anné Dr. Joleen Masschelein 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10636-10643
The enoyl-acyl carrier protein reductase enzyme FabI is essential for fatty acid biosynthesis in Staphylococcus aureus and represents a promising target for the development of novel, urgently needed anti-staphylococcal agents. Here, we elucidate the mode of action of the kalimantacin antibiotics, a novel class of FabI inhibitors with clinically-relevant activity against multidrug-resistant S. aureus. By combining X-ray crystallography with molecular dynamics simulations, in vitro kinetic studies and chemical derivatization experiments, we characterize the interaction between the antibiotics and their target, and we demonstrate that the kalimantacins bind in a unique conformation that differs significantly from the binding mode of other known FabI inhibitors. We also investigate mechanisms of acquired resistance in S. aureus and identify key residues in FabI that stabilize the binding of the antibiotics. Our findings provide intriguing insights into the mode of action of a novel class of FabI inhibitors that will inspire future anti-staphylococcal drug development. 相似文献
129.
The crystals of the iron(II)-thioglycolic acid complex 1-1, Fe(CH2SCOO)·H2O, are monoclinic, with lattice constants a = 7.54±0.02 Å, b = 8.57±0.01 Å, c = 6.95±0.01 Å and β = 90° 57′±9′. The space group is P21/c, each unit cell containing four entities Fe(CH2SCOO)·H2O. The structure consists of sheets of iron-sulfur chain assemblies. The iron atoms of two chains are connected by double oxygen bridges and thioglycolic anions; each iron is at the center of a highly distorted octahedron. 相似文献
130.
Jean -Jacques Bonnet Guy Lavigne Foune Papageorgiou 《Journal of chemical crystallography》1986,16(4):475-482
The title compound is Ru3(-Cl)2(CO)8(PPh3)2. Crystal data: formula C44H30O8Cl2P2Ru3;f
w
=1122.9; monoclinic,P21; cell parameters (at 293 K)a=10.971(2) Å,b=17.066(2) Å,c=11.833(2) Å,=92.91(1)°,V=2213 Å3,Z=2,
calcd=1.68,
meas=1.68. Final discrepancy indices areR(F)=0.030,R
W
(F)=0.036. The structure consists of an open trinuclear unit involving two metal-metal bonds [Ru(1)-Ru(2)=2.845(1) Å, Ru(2)-Ru(3)=2.860(1) Å]. The open edge of the metal framework [Ru(1)Ru(3)=3.254(1) Å] is supported by two symmetric bridging chloride ligands [Cl(1)-Ru(1)=2.461(2) Å; Cl(1)-Ru(3)=2.464(2) Å; Cl(2)-Ru(1)=2.470(2) Å; Cl(2)-Ru(3)=2.472(2) Å]. Both phosphorus ligands are cis to the Cl atoms and trans to the unique ruthenium atom Ru(2). Geometric features of the edge dibridged complex are discussed. 相似文献