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31.
Hitchcock PB Lappert MF Liu DS Sablong R 《Chemical communications (Cambridge, England)》2002,(17):1920-1921
The compounds [K((mu-N(SiMe3)C(Ph))2CH)(thf)2]infinity 1, [K(mu-N(SiMe3)C(Ph)C(H)C(Ph)NH)L]2 [L = (thf)2 2, tmen 3], [K(mu-NSi(Me)2C(Ph)C(H)C(Ph)N)(thf)3]2 4 and [K(N(H)C(Ph))2CH](thf)0.5 5 have been prepared from K[(N(SiMe3)C(Ph))2CH] and the X-ray structures of 1-4 are reported. 相似文献
32.
The aim of this work was the preparation of enantiomerically pure bis(pinene-bipyridine) ligands containing the ferrocenyl moiety. Several such ligands (1-3) were synthesized and completely characterized. These molecules can be diastereoselectively deprotonated at the acidic methylene group of the pinene moiety using a strong and sterically hindered base such as LDA. Subsequent reaction of the formed anion with alkyl halides yield the family of C(2)-symmetric enantiopure compounds (1a-c). Copper(I), silver(I), or zinc(II) complexes with several ligands (C1-C8) were prepared and structurally characterized in the solid state and in solution. Self-assembled helical species are formed in several cases. It became evident that the chiral groups present in the ligand do not completely determined the helical configuration of the assemblages. Diastereoselectivity is thus not complete with this type of ligands, contrary to other, similar ligands studied before. 相似文献
33.
GITR (glucocorticoid-induced TNF receptor) is a recently identified member of the TNF receptor superfamily. The receptor is preferentially expressed on CD4(+)CD25(+) regulatory T cells and GITR signals break the suppressive activity of the subset. In this study, we wanted to reveal the in vivo function of GITR in herpes simplex virus type 1 (HSV-1) infection. A single injection of anti-GITR mAb (DTA-1) immediately after viral infection significantly increased the number of CD4(+) and CD8(+) T cells expressing CD25, an activation surface marker, and secreting IFN-gamma. We confirmed these in vivo observations by showing ex vivo that re-stimulation of CD4(+) or CD8(+) T cells with a CD4(+) or CD8(+) T-cell-specific HSV-1 peptide, respectively, induced a significant elevation in cell proliferation and in IFN-gamma secretion. Our results indicate that GITR signals play a critical role in the T-cell immunity to HSV-1. 相似文献
34.
Geney R Sun L Pera P Bernacki RJ Xia S Horwitz SB Simmerling CL Ojima I 《Chemistry & biology》2005,12(3):339-348
A new computational docking protocol has been developed and used in combination with conformational information inferred from REDOR-NMR experiments on microtubule bound 2-(p-fluorobenzoyl)paclitaxel to delineate a unique tubulin binding structure of paclitaxel. A conformationally constrained macrocyclic taxoid bearing a linker between the C-14 and C-3'N positions has been designed and synthesized to enforce this "REDOR-taxol" conformation. The novel taxoid SB-T-2053 inhibits the growth of MCF-7 and LCC-6 human breast cancer cells (wild-type and drug resistant) on the same order of magnitude as paclitaxel. Moreover, SB-T-2053 induces in vitro tubulin polymerization at least as well as paclitaxel, which directly validates our drug design process. These results open a new avenue for drug design of next generation taxoids and other microtubule-stabilizing agents based on the refined structural information of drug-tubulin complexes, in accordance with typical enzyme-inhibitor medicinal chemistry precepts. 相似文献
35.
A.J. Poë 《Journal of organometallic chemistry》1975,94(2):235-239
Pt(CO)2Cl2 reacts in benzene, toluene or tetrahydrofuran with 3-hexyne to give carbonylplatinumbis[di-μ-chloro,chloro(tetraethylcyclobutadiene)platinum](I), bis[dichloro(tetraethylcyclopentadienone)platinum] (III), dichloro-(tetraethyl-p-benzoquinone)platinum (IV) and dichloro(tetraethylcyclobutadiene)platinum (II). This last compound is also obtained by treating I with 1 to 3 moles of triphenylphosphine or p-toluidine. p ]The structure and reactions of III are discussed; the anion exchange reaction gives the iodo-analogue, while treatment with donor ligands gives adducts of formula [(C2H5)4C4CO]PtCl2L(L = triphenylphosphine, p-toluidine, benzylamine and pyridine) and [(C2H5)4C4CO]PtCl2L2(L = benzylamine, 3-methylpyridine). p ]2-Butyne reacts with dichlorodicarbonylplatinum to give the methyl analogous of compounds I–III. 相似文献
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39.
Anthony Poë 《Journal of organometallic chemistry》1976,120(1):C20-C21
The palladium(I) and platinum(I) complexes [(CH3NC)6M2]2+ undergo substitution reactions with isocyanides, phosphines and halide or pseudohalide ions. With triphenylphosphine, axial substitution is preferred. The product [(CH3NC)5(Ph3P)Pd2]2+ is fluxional. 相似文献
40.
N.E. Schore B.E. La Belle M.J. Knudsen H. Hope X-J. Xu 《Journal of organometallic chemistry》1984,272(3):435-446
Dicobalt octacarbonyl is shown to react with acetylene and carbon monoxide under mild conditions in dimethoxyethane or benzene to produce, in low yields, bicyclo[3.3.0]octa-3,7-diene-2,6-dione, benzoquinone, and the cyclopentadienone-derived products 3a,4,7,7a-tetrahydro-2,7-methanoindene-1,10-dione, 1-indanone, tetracyclo[5.5.2.02,608,12]tetradeca-4,10,13-triene-3,9-dione, and tetracyclo[5.5.2.02,608,12]tetradeca-4,9,13-triene-3,11-dione. Possible mechanisms for the formation of these products are discussed. 相似文献