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31.
A convenient route to new 3-quinolinonyl-pyrazoles and isoxazoles is described through cyclization of 3-[(E)-3-(dimethylamino)-2-propenoyl]-4-hydroxy-1-methyl-2(1H)-quinolinone. The phototoxicity as well as the cytotoxic activities of the title compounds are evaluated against leukemia- and adenocarcinoma-derived cell lines in comparison to the normal human keratinocytes. 相似文献
32.
Giovannelli Tommaso Liuzzi Giampaolo Lucidi Stefano Rinaldi Francesco 《Computational Optimization and Applications》2022,82(2):293-327
Computational Optimization and Applications - In this paper, mixed-integer nonsmooth constrained optimization problems are considered, where objective/constraint functions are available only as the... 相似文献
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Some results on configurations realizing minimum blocking sets of a finite projective plane are obtained by introducing a suitable attraction property.Dedicated to Professor M. Scafati Tallini on the occasion of her 65th birthday 相似文献
35.
Copper(II) complexes with the herbicide N-(phosphonomethyl)glycine (glyphosate) have been investigated in aqueous solution by means of pH-metric measurements at different temperatures, 5 = T = 45 degrees C, calorimetry and visible spectrophotometry. Potentiometric data, at all the considered temperatures in the range 2.5 = pH = 10.5, can be explained assuming the formation of the species CuLH(0), CuL(-), CuLH(2 -)(- 1), CuL(4 -)(2) and Cu(2)L(+). By using thermodynamic data and calculated electronic spectra for each complex a structural definition is proposed for the different species. Copper(II)-glyphosate complexes are quite stable and must be taken into account in the speciation of natural fluids. 相似文献
36.
M. Curini A. Bianchi F. Epifano R. Bruni L. Torta A. Zambonelli 《Chemistry of Natural Compounds》2003,39(2):191-194
Essential oils of Erigeron canadensis L. and Myrtus communis L. were tested in vitro as growth inhibitors against phytopathogenic fungi Rhizoctonia solani Kuhn, Fusarium solani (Mart.) Sacc. and Colletotrichum lindemuthianum (Sacc. & Magn.) Briosi & Cav. Both showed weak fungicidal acitivity, except the essential oil of M. communis that exerted a 60% growth inhibition against R. Solani at a dose of 1600 ppm. Microscopic observation revealed that the essential oil of M. Communis caused morphological alterations of hyphae of all fungi at 1600 ppm, while, at the same dose, only the hyphal morphology of C. Lindemuthianum was affected by the essential oil of Er. Canadensis. 相似文献
37.
Carlo Mealli Stefano Midollini Simonetta Moneti Thomas A. Albright 《Helvetica chimica acta》1983,66(2):557-569
The reaction of [(C3Ph3)Ni(PPh3)2]ClO4 with P(CH2CH2PPh2)3(pp3) and NaBPh4 yields the [(C3Ph3)Ni(pp3)]BPh4-complex. After long exposure of the solution of this compound in acetone/butanol to the air a new derivative [(C3Ph3)-Ni(pp2po)]BPh4· 0.5 C4H9OH, where pp2po is (Ph2PCH2CH2)2P(CH2 CH2POPh2), is obtained. Complete X-ray analysis has been carried out for the latter complex: a=18.303 (5); b=29.445 (6), c=13.305 (5) Å, β=112.70 (9)°; space group monoclinic, P21/a, Z=4. Disorder problems were encountered in the refinement of the structure. The best R is 0.093. One of the arms of the parent pp3-molecule, not coordinated to the metal, undergoes oxidation. The Ni-atom, coordinated by the three remaining P-atoms of the ligand, is also linked in a roughly η3-mode to the cyclopropenium ligand. The geometry of the molecule is examined in detail. Extended HMO-calculations were performed to interpret how the variation of P? Ni? P angles affects the bonding between the NiP3- and C3H3-fragments. The conclusion is that the overall energy of the complex may be lowered in spite of a weakening of the Ni-cyclopropenium linkage. Extensions are made to other systems containing a linkage between a metal and a X3-ring (X=P,As). 相似文献
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Riccò M Shiroka T Carretta S Bolzoni F Femoni C Iapalucci MC Longoni G 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(9):2856-2861
The magnetic behaviour of the even-electron [Ni16Pd16(CO)40]4- cluster, in its [NnBu4]+ salt, has been investigated by magnetometry and muon spin rotation/relaxation (muSR) spectroscopy. The susceptibility measurements show an exceptionally high magnetic moment corresponding to a total spin value J=2. This suggests a Hund filling of a quadruplet ground state, quite unique in carbonyl-metal clusters. SQUID magnetometry shows a departure from the Curie-Weiss law, for T>150 K, and strong deviation from a Brillouin behaviour of the magnetisation curves. muSR spectroscopy in zero applied field shows a temperature independent decay of the muon spin polarisation, similar to that of a purely paramagnetic system. The observed muon spin repolarisation in a moderate external longitudinal field, however, invalidates this simple picture and suggests the presence of a local anisotropy field acting on the cluster's magnetic moment. A consistent interpretation of magnetometry and muSR results implies the occurrence of an additional interaction of the cluster spin with an effective crystalline field. The inclusion of this interaction in a model Hamiltonian allows us to successfully reproduce both the susceptibility and magnetisation data. 相似文献