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971.
合成了β-芳氧基丙酸芳酯及β-芳氧基丙酰芳胺等17种化合物,经IR,UV,HNMR和元素分析确定了它们的结构,并对它们的生物活性进行了初步考察。 相似文献
972.
Koji Yagi Veronica Garcia Ma. E. Rivas Javier Salas Andres Camargo Takeo Tabata 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(1-2):179-184
Some crown ethers were found to show significant antifungal activity against some wood-decay fungi, phytopathogenic fungi and eumycetes,Trichophytons for dermatomycosis. Their toxicity was evaluated by the paper disc method as well as by determining the values of ED50, i.e., the concentration which inhibits the mycelium growth by 50%. The fungi examined areTyromyces palustris, Picnoporous coccineus, Coriolous versicolor, Pyricularia filamentosa, Fusarium sp., Trichophyton rubrum, Trichophyton sp., etc. Among the 26 crown ethers tested, 3,5-di-t-butyl-benzo-15-crown-5 showed relatively high activity, the highest ED50 value of which being 8 M or 3 ppm. Other alkylbenzocrown ethers, dicyclohexyl crown ethers and Kryptofix 22DD also showed considerable activity. On the other hand, unsubstituted crown ethers, benzocrown ethers with a polar substituent, Kryptofix 222B and Kryptofix 221 were inactive. 相似文献
973.
Wei Jun Jin 《Analytica chimica acta》2004,522(1):1-8
Luminescent surface-modified CdSe semiconductor quantum dots (QDs), with nanoparticle (NP) size distribution in the order of 2-7 nm, have been synthesized for optical determination of cyanide ions. The nanoparticles have been functionalised with tert-butyl-N-(2-mercaptoethyl)-carbamate (BMC) groups and exhibit a strong fluorescent emission at about 580 nm with rather long fluorescence lifetimes (several hundred nanoseconds) in aerated methanolic solution. The observed luminescence emitted by the synthesized nanocrystals was tremendously increased by photo-activation under sunlight exposure. The functionalised QDs turned out to exhibit excellent long-term stability when stored in the dark (no significant changes in QDs luminescence emission intensity was observed even after two months from synthesis). The functionalisation of the NPs with carbamate ligand allowed a highly sensitive determination of free cyanide via analyte-induced changes in the photoluminescence (fluorescence quenching of intensity at 580 nm and lifetime changes) of the modified quantum dots (excited at 400 nm). A detection limit of 1.1 × 10−7 M (2.9 μg l−1) of cyanide ions was obtained, while the interfering effect of other inorganic anions (including NO3−, Cl− or SCN−) was negligible even at 200-fold level concentrations in excess of cyanide. 相似文献
974.
The mouse immunoglobulin G (mouse IgG) as a kind of bio-molecule was labeled with two different luminescent colloidal semiconductor quantum dots (QDs), green-emitting CdTe quantum dots and red-emitting CdTe quantum dots in this work. As a result of the fluorescence resonance energy transfer (FRET) between the two different sizes nanoparticles with mouse IgG as the binding bridge, a significant enhancement of the emission of the red-emitting CdTe quantum dots and the corresponding quenching of the emission of green-emitting CdTe quantum dots were observed. The relationship between the concentration of the mouse immunoglobulin G and the fluorescence intensity ratio (Ia/Id) of acceptors and donors was studied also. Under optimal conditions, the calibration graph is linear over the range of 0.1–20.0 mg/L mouse IgG. 相似文献
975.
Xu-Fang Chen Li Liu Jian-Gong Ma Long Yi Peng Cheng Dai-Zheng Liao Shi-Ping Yan Zong-Hui Jiang 《Journal of Molecular Structure》2005,750(1-3):94-100
A series of chromium(III) complexes [Cr(bipy)(HC2O4)2]Cl·3H2O (1), [Cr(phen)(HC2O4)2]Cl·3H2O (2), [Cr(phen)2(C2O4)]ClO4 (3), [Cr2(bipy)4(C2O4)](SO4)·(bipy)0.5·H2O (4) and [Mn(phen)2(H2O)2]2[Cr(phen)(C2O4)2]3ClO4·14H2O (5) were synthesized (bipy=4,4′-bipyridine, phen=1,10-phenanthroline), while the crystal structures of 1 and 3–5 have been determined by X-ray analysis. 1 and 3 are mononuclear complexes, 4 contains binuclear chromium(III) ions and 5 is a 3D supromolecule formed by complicated hydrogen bonding. 1–3 are potential molecular bricks of chromium(III) building blocks for synthesis heterometallic complexes. When we use these molecular bricks as ligands to react with other metal salts, unexpected complexes 4 and 5 are isolated in water solution. The synthesis conditions and reaction results are also discussed. 相似文献
976.
HUANG Wei-Ping ZHANG Xin-Jie WU Shi-HuaMA Shu-Yin ZHANG Shu-Ji ZHAO Wei-Jun 《天然气化学杂志》1997,6(3):252-257
IntroductionIn1962,N.V.Kutepow'SgroupfirstusedcomplexesofFe,CoandNiascatalyststocatalyzecarboXylationofethanoltopreparepropanoicacidanditsderivants.Thereactionpressurewashighandtheyieldwaslow.LateronPaulalsandhiscolleagueusedabC13andiodineascatalyst,which… 相似文献
977.
The alkyl (aryl)-bishydroxymethylphosphines react with primary amines to give the title compounds. With optically active amines optically active phosphines are formed. 相似文献
978.
The nitrosyl-hemoglobin (HbNO) is the carrier of nitric oxide (NO) which is the important messenger molecule displaying multiple physiologic and pathophysiologic roles. However it is still not clear for the fate of HbNO molecules during the venous-arterial transit. In this letter, the HbNO transition in vitro was studied by using the electron paramagnetic resonance (EPR) spectra. It was found that HbNO molecules were stable when oxygen did not exist in the system but not stable in aerobic conditions. The absorption spectra further revealed that the methemoglobin (metHb) was the product of HbNO in aerobic environment, showing that the HbNO changed to metHb when there were enough oxygen molecules in the system. 相似文献
979.
1—酰基—4—氯环己烷与取代芳烃的区域与立体选择性反应 总被引:2,自引:0,他引:2
从环己烯合成了1-酰基-4-氯环己烷,发现在其在AlCl3催化与苯,氯苯,溴苯等优先生成反式1-芳基-4-酰基环己烷,与联苯反应时选择性较差。 相似文献
980.
P. Molina Ma. J. Vilaplana P. L. Andreu J. Mller 《Journal of heterocyclic chemistry》1987,24(5):1281-1284
N-Aryl-N-(α-phenylphenacyl)oxamoyl chlorides react with N3-arylsubstituted amidrazones to give functionalized 1,2,4-triazoles which undergo ring-closure by the action of thionyl chloride to give 1,2,4-triazolo[1,5-a]-pyrazinium chlorides in excellent yields. 相似文献