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61.
Martinez-Diaz MV Rodriguez-Morgade MS Feiters MC van Kan PJ Nolte RJ Stoddart JF Torres T 《Organic letters》2000,2(8):1057-1060
[formula: see text] New unsymmetrically substituted DB24C8-phthalocyanines, which are able to form complexes with suitable dialkylammonium cations, have been prepared. These complexes most probably have a pseudorotaxane geometry. 相似文献
62.
The advantages and technical problems related to the on-line connection of liquid chromatography and mass spectrometry are described, with special emphasis on applications in pharmaceutical chemistry. The most important characteristics of various interfaces, such as direct liquid introduction, Magic, continuous flow fast atom bombardment and thermospray, are discussed. Special applications to the study of thermally very labile compounds are considered. 相似文献
63.
Haiwen Zhang David W. Norman Tracey M. Wentzell Alison M. Irving Janet P. Edwards Susan L. Wheaton Christopher M. Vogels Stephen A. Westcott Felix J. Baerlocher Andreas Decken 《Transition Metal Chemistry》2005,30(1):63-68
Reactions of salicylaldehydes with boronate ester derivatives of aniline have been examined. Addition of these Schiff base ligands to palladium acetate or Na2PdCl4 afforded novel boron-containing trans-bis(N-arylsalicylaldiminato) palladium complexes.Condensation of salicylaldehyde (2-HOC6H4C(O)H) with H2NC6H4Bpin (pin=1,2-O2C2Me4) afforded the boron-containing Schiff bases, 2-HOC6H4C(H)=NC6H4Bpin (1–3a). Similar reactivity with 2-hydroxy-5-nitrobenzaldehyde and 2-hydroxy-1-naphthaldehyde gave the corresponding Schiff bases (1-3b) and (1-3c), respectively. Reaction of Schiff bases (2) and (3) with palladium acetate or Na2PdCl4 afforded complexes of the type PdL2
(4,5), where L=deprotonated Schiff base. The molecular structure of the nitro-salicylaldehyde 4-Bpin palladium complex (5b) was characterized by an X-ray diffraction study. All new palladium compounds have been characterized fully and tested for their antifungal activity against Aspergillus niger and Aspergillus flavus. 相似文献
64.
An automated Flow-Injection Liposome ImmunoAnalysis (FILIA) system has been modified from a previous design, using a specific environmental contaminant, the herbicide alachlor, as a model analyte. Signal amplification by means of fluorescent marker-loaded, analyte-tagged liposomes provides high sensitivity. The computer controlled system is composed of commercially available components, with the exception of the column packing material, which has to be prepared for each specific analyte to be determined. The use of such components means that the system is easily modified. The relationships between antibody concentration and assay speed and sensitivity are explored, and the possibilities of using the system for determination of multiple analytes is discussed. 相似文献
65.
The room-temperature diffuse-reflectance spectra of compositions within the Li1+xTi2?xO4 spinel system () show three absorption bands in the range 4000 to 48,000 cm?1. Two high-energy absorption bands correspond to charge-transfer transitions from the oxygen-2p valence band to the titanium t2g and σ1 conduction bands, where the σ1 band of eg character has hybridized titanium-3d and titanium-4s parentage. The absorption band arising from promotion of electrons to the empty σ1 band does not alter with composition whereas the absorption band arising from promotion of electrons to the partially filled t2g band narrows as the concentration of conduction electrons in the t2g band decreases. These two high-energy absorption bands fall entirely within the ultraviolet spectral region, and the absorption edge in occurs at 24,300 cm?1 (3.02 eV). A low-energy absorption band is observed in compositions with and in samples of reduced in hydrogen at elevated temperatures. This band straddles the boundary between the visible and infrared spectral regions and shifts toward lower energy as the concentration of conduction electrons in the t2g band decreases. The possible origins of the band are discussed; the argument is in favor of a d-d interband transition from states in the partially filled t2g band to states in the empty σ1 band. 相似文献
66.
M. L. Edwards 《Journal of heterocyclic chemistry》1980,17(2):383-384
Amidoalkylation of three benzoheterocycles, benzimidazole-2-one, 1,3-dihydrobenzo[c]-thiophene 2,2-dioxide and 1,3-dihydro-2,1,3-benzothiadiazole using N-acylhippuric acids was successful. The corresponding phenylglycine analogs were prepared by removal of the N-acyl protecting group. 相似文献
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