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1.
G. D. Andreetti F. Ugozzoli A. G. Giumanini P. Traldi L. Lassiani A. Varnavas 《Journal of chemical crystallography》1991,21(6):721-728
The decomposition of the gaseous positive ions of the title compounds obtained by electron impact have been completely mapped. The X-ray structural determinations of these two substances established their identity definitively and allowed to reveal some interesting features of these molecules of pharmaceutical interest. 相似文献
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Arduini A Ferdani R Pochini A Secchi A Ugozzoli F 《Angewandte Chemie (International ed. in English)》2000,39(19):3453-3456
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Arduini A Bohmer V Delmau L Desreux JF Dozol JF Carrera MA Lambert B Musigmann C Pochini A Shivanyuk A Ugozzoli F 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(12):2135-2144
Conformationally rigidified tetraCMPO derivatives have been prepared from calix[4]arene bis(crown ether) 4a in which adjacent oxygens are bridged at the narrow rim by two diethylene glycol links. Acylation of the tetraamine 4c with the CMPO-active ester 5b gave the tetraphosphine oxide 6a, while the tetraphosphinate 6b and the tetraphosphonate 6c were obtained by Arbuzov reaction of tetrabromoacetamido derivative 7 with PhP(OEt)2 or P(OEt)3. The extraction ability of these CMPO derivatives was checked for selected lanthanides and actinides and compared with the analogous compounds 1b, 10b and 10d derived from calix[4]arene tetrapentyl ether. All rigidified bis(crown ether) ligands are more effective extractants than their pentyl ether counterparts and require only 1/10 of the concentration (cL= 10 4M) to obtain the same distribution coefficients, while with CMPO itself a 2,000-fold concentration is necessary. This could be a consequence of a better preorganisation of the ligating functions owing to the rigidity which on the other hand did not change the observed selectivity for americium (DAm/DEu=9-19) and for light lanthanides over heavy ones. NMR relaxivity titration curves show that the complex of Gd3+ with ligand 6a is highly oligomerised in anhydrous acetonitrile over a large range of ligand:metal concentration ratios. Nuclear magnetic relaxation dispersion (NMRD) profiles also showed that large oligomers were formed, and their mean tumbling times were deduced from the Solomon-Bloembergen-Morgan equations. The NMR spectra of dia- and paramagnetic lanthanide complexes with 6a agreed with the presence of two conformers with an elongated calix[4]arene skeleton in which the distances between opposite methylene groups are different. Contrary to what was observed with ligand 2a, the addition of nitrate ions does not labilize the metal complexes, presumably because of the rigidification effect of the ether bridges. Single-crystal X-ray structures were obtained for the active ester 5b and for diphenylphosphorylacetic acid 5a. 相似文献
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Anna Maria Manotti Lanfredi Franco Ugozzoli Annamaria Camus 《Journal of chemical crystallography》1996,26(2):141-145
The title compound was obtained from a CS2 solution of bis(2,2-dipyridylamido)copper(II), by insertion of solvent into this complex. In the structure of the dithiocarbamate the metal atom is approximately square-planar coordinated by four S atoms from two chelating ligands. Considering the long interactions between the metal center and the S(2) atom from a centrosymmetrically related complex [Cu(1)...S(2)=3.230 Å], double bridged dimers are formed with the copper atoms in an elongated square-pyramidal coordination. The crystals are monoclinic, space groupP2
1/n witha=14.549(3),b=11.662(3)c=15.329(4) Å and =114.79(2)°. 相似文献
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Lucedio Greci Mirco Pieroni Giorgio Tosi Corrado Rizzoli Paolo Sgarabotto Franco Ugozzoli 《Journal of chemical crystallography》1991,21(6):693-699
Methyl and methoxy substituted nitroarenes were reacted with acethophenone in the presence of sodium ethoxide in ethanol giving arylamino-conjugated diketo derivatives. A case ofipso-substitution of a methoxy group is discussed. The title compound C23H19NO2 (M
r
=341.4) crystallizes in the monoclinic system, space groupP21/n witha=21.579(4),b=8.526(2),c=9.983(2) Å;=92.3(1)°;V=1835.2(7) Å3,Z=4,D
c
=1.24 g cm–3,(Cu-K
)=5.9 cm–1, =1.5418 Å,F(000)=720. The molecule adopts theE configuration with the C=O carbonyl groupstrans with respect to the ethylenic double bond. 相似文献
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