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71.
Bollermann T Schwedler I Molon M Freitag K Gemel C Seidel RW Fischer RA 《Dalton transactions (Cambridge, England : 2003)》2011,40(46):12570-12577
The reactions of heteroleptic GaCp*/CO containing transition metal complexes of iron and cobalt, namely [(CO)(3)M(μ(2)-GaCp*)(m)M(CO)(3)] (Cp* = pentamethylcyclopentadienyl; M = Fe, m = 3; M = Co, m = 2) and [Fe(CO)(4)(GaCp*)], with ZnMe(2) in toluene and the presence of a coordinating co-solvent were investigated. The reaction of the iron complex [Fe(CO)(4)(GaCp*)] with ZnMe(2) in presence of tetrahydrofurane (thf) leads to the dimeric compound [(CO)(4)Fe{μ(2)-Zn(thf)(2)}(2)Fe(CO)(4)] (1). Reaction of [(CO)(3)Fe(μ(2)-GaCp*(3))Fe(CO)(3)] with ZnMe(2) and stoichiometric amounts of thf leads to the formation of [(CO)(3)Fe{μ(2)-Zn(thf)(2)}(2)(μ(2)-ZnMe)(2)Fe(CO)(3)] (2) containing {Zn(thf)(2)} as well as ZnMe ligands. Using pyridine (py) instead of thf leads to [(CO)(3)Fe{μ(2)-Zn(py)(2)}(3)Fe(CO)(3)] (3) via replacement of all GaCp* ligands by three{Zn(py)(2)} groups. In contrast, reaction of [(CO)(3)Co(μ(2)-GaCp*)(2)Co(CO)(3)] with ZnMe(2) in the presence of py or thf leads in both cases to the formation of [(CO)(3)Co{μ(2)-ZnL(2)}(μ(2)-ZnCp*)(2)Co(CO)(3)] (L = py (4), thf (5)) via replacement of GaCp* with {Zn(L)(2)} units as well as Cp* transfer from the gallium to the zinc centre. All compounds were characterised by NMR spectroscopy, IR spectroscopy, single crystal X-ray diffraction and elemental analysis. 相似文献
72.
On irradiation (350 nm) in the presence of 2,3‐dimethylbuta‐1,3‐diene, benzoxepinone 2 and dioxepinone 3 were converted regio‐ and diastereoselectively to trans‐fused oxabicyclo[5.2.0]nonanones 5 and 9 , respectively. 相似文献
73.
Bollermann T Freitag K Gemel C Molon M Seidel RW von Hopffgarten M Jerabek P Frenking G Fischer RA 《Inorganic chemistry》2011,50(20):10486-10492
The synthesis, structural characterization, and bonding situation analysis of a novel, all-zinc, hepta-coordinated palladium complex [Pd(ZnCp*)(4)(ZnMe)(2){Zn(tmeda)}] (1) is reported. The reaction of the substitution labile d(10) metal starting complex [Pd(CH(3))(2)(tmeda)] (tmeda = N,N,N',N'-tetramethyl-ethane-1,2-diamine) with stoichiometric amounts of [Zn(2)Cp*(2)] (Cp* = pentamethylcyclopentadienyl) results in the formation of [Pd(ZnCp*)(4)(ZnMe)(2){Zn(tmeda)}] (1) in 35% yield. Compound 1 has been fully characterized by single-crystal X-ray diffraction, (1)H and (13)C NMR spectroscopy, IR spectroscopy, and liquid injection field desorption ionization mass spectrometry. It consists of an unusual [PdZn(7)] metal core and exhibits a terminal {Zn(tmeda)} unit. The bonding situation of 1 with respect to the properties of the three different types of Zn ligands Zn(R,L) (R = CH(3), Cp*; L = tmeda) bonded to the Pd center was studied by density functional theory quantum chemical calculations. The results of energy decomposition and atoms in molecules analysis clearly point out significant differences according to R vs L. While Zn(CH(3)) and ZnCp* can be viewed as 1e donor Zn(I) ligands, {Zn(tmeda)} is best described as a strong 2e Zn(0) donor ligand. Thus, the 18 valence electron complex 1 nicely fits to the family of metal-rich molecules of the general formula [M(ZnR)(a)(GaR)(b)] (a + 2b = n ≥ 8; M = Mo, Ru, Rh; Ni, Pd, Pt; R = Me, Et, Cp*). 相似文献
74.
Structure-activity-based design of a synthetic malaria peptide eliciting sporozoite inhibitory antibodies in a virosomal formulation 总被引:1,自引:0,他引:1
Okitsu SL Kienzl U Moehle K Silvie O Peduzzi E Mueller MS Sauerwein RW Matile H Zurbriggen R Mazier D Robinson JA Pluschke G 《Chemistry & biology》2007,14(5):577-587
The circumsporozoite protein (CSP) of Plasmodium falciparum is a leading candidate antigen for inclusion in a malaria subunit vaccine. We describe here the design of a conformationally constrained synthetic peptide, designated UK-39, which has structural and antigenic similarity to the NPNA-repeat region of native CSP. NMR studies on the antigen support the presence of helical turn-like structures within consecutive NPNA motifs in aqueous solution. Intramuscular delivery of UK-39 to mice and rabbits on the surface of reconstituted influenza virosomes elicited high titers of sporozoite crossreactive antibodies. Influenza virus proteins were crucially important for the immunostimulatory activity of the virosome-based antigen delivery system, as a liposomal formulation of UK-39 was not immunogenic. IgG antibodies elicited by UK-39 inhibited invasion of hepatocytes by P. falciparum sporozoites, but not by antigenically distinct P. yoelii sporozoites. Our approach to optimized virosome-formulated synthetic peptide vaccines should be generally applicable for other infectious and noninfectious diseases. 相似文献
75.
Ruud Peters Ingrid Elbers Anna Undas Eelco Sijtsma Sophie Briffa Pauline Carnell-Morris Agnieszka Siupa Tae-Hyun Yoon Loïc Burr David Schmid Jutta Tentschert Yves Hachenberger Harald Jungnickel Andreas Luch Florian Meier Jovana Kocic Jaeseok Kim Byong Chon Park Barry Hardy Colin Johnston Kerstin Jurkschat Jrg Radnik Vasile-Dan Hodoroaba Iseult Lynch Eugenia Valsami-Jones 《Molecules (Basel, Switzerland)》2022,27(15)
76.
Expression of Hepatoma-derived growth factor family members in the adult central nervous system 总被引:1,自引:0,他引:1
Heba M El-Tahir Frank Dietz Ralf Dringen Kerstin Schwabe Karen Strenge S?rge Kelm Mekky M Abouzied Volkmar Gieselmann Sebastian Franken 《BMC neuroscience》2006,7(1):6
Background
Hepatoma-derived growth factor (HDGF) belongs to a polypeptide family containing five additional members called HDGF related proteins 1–4 (HRP-1 to -4) and Lens epithelial derived growth factor. Whereas some family members such as HDGF and HRP-2 are expressed in a wide range of tissues, the expression of others is very restricted. HRP-1 and -4 are only expressed in testis, HRP-3 only in the nervous system. Here we investigated the expression of HDGF, HRP-2 and HRP-3 in the central nervous system of adult mice on the cellular level by immunohistochemistry. In addition we performed Western blot analysis of various brain regions as well as neuronal and glial cell cultures. 相似文献77.
78.
Optimal lower bounds for cubature error on the sphere 总被引:6,自引:1,他引:5
We show that the worst-case cubature error E(Qm;Hs) of an m-point cubature rule Qm for functions in the unit ball of the Sobolev space Hs=Hs(S2),s>1, has the lower bound , where the constant cs is independent of Qm and m. This lower bound result is optimal, since we have established in previous work that there exist sequences of cubature rules for which with a constant independent of n. The method of proof is constructive: given the cubature rule Qm, we construct explicitly a ‘bad’ function fmHs, which is a function for which Qmfm=0 and . The construction uses results about packings of spherical caps on the sphere. 相似文献
79.
A novel convenient synthetic route for poly-functional 21-monothiatetraphenylporphyrins of the type A4 und AB3 having base labile substituents in meso position was developed. Using this method a series of symmetric and asymmetric 21-thiaporphyrins containing different functional groups at the meso position is reported. The new products were characterized by NMR, UV-Vis and mass spectroscopy. 相似文献
80.