共查询到20条相似文献,搜索用时 15 毫秒
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El Sayed H. El Ashry Mohamed M.A. Abdel Rahman Mahmoud A. Nassr Adel Amer 《Carbohydrate research》1978,67(2):403-414
The difference in reactivity of the two amino groups in 4-chloro-o-phenylene-diamine allowed it to react with l-threo-2,3-hexodiulosono-1,4-lactone to give, after further reaction with various hydrazines, 6-chloro-3-(1-substituted-hydrazono-l-threo-2,3,4-trihydroxybutyl)-2-quinoxalinones (5-14), whose structures were deduced from their reactions, as well as from mass spectrometry of the (p-nitrophenyl)-hydrazone. Elimination of one mole of water per mole from these hydrazones gave the 1-aryl-6-chloro-3-(l-threo-glycerol-1-yl)flavazoles; the mass spectrum of one of these flavazoles is discussed. Elimination of two moles of water per mole from the hydrazones (5, 7, and 8) occurred with simultaneous cyclization to give 3-[l-aryl-5- (hydroxymethyl)pyrazol-3-yl]-6-chloro-2-quinoxalinones. whose acetylation gave the corresponding- monoacetyl derivatives (that could also be obtained by the action of boiling acetic anhydride on the starting hydrazones). Periodate oxidation of the hydrazones and the flavazole derivatives afforded the corresponding aldehydes (that could react with hydrazines). 相似文献
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Muhammad Amjad Sajjad H. Sumrra Muhammad Safwan Akram 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):88-97
AbstractMetal-based ethanolamines, (L1)–(L4) coordinated with Co(II), Cu(II), Ni(II) and Zn(II) metals in 1:2 (metal:ligand) molar ratio to produce new compounds have been reported. These compounds were screened for their bactericidal/fungicidal activity against a number of bacterial (Escherichia coli, Shigella flexneri, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus and Bacillus subtilis) and fungal strains (Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glabrata) alongside against a shrimp species known as Artemia salina. The screening results indicated that metal complexes have significantly higher activity than uncomplexed ligands against one or more bacterial/fungal species due to chelation. The ligand (L4) displayed good bacterial and fungal activity as compared to other ligands. The antibacterial results revealed that the Zn(II) complex (16) of (L4) was found to be the most active complex and Co(II) complex (14) of the same ligand (L4), demonstrated the highest antifungal activity. 相似文献
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A selective medium containing 6 μg/ml furoxone was developed for routine isolation of cutaneous propionibacteria from mixed floras including staphylococci. 相似文献
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Fractionation of sediment phosphate with chelating compounds: a simplification, and comparison with other methods 总被引:20,自引:2,他引:20
H. L. Golterman 《Hydrobiologia》1996,335(1):87-95
The NTA/EDTA fractionation of sediment-bound, inorganic phosphate was improved and made more effective. The iron-bound phosphate
is now extracted with Ca-EDTA plus dithionite and followed by an extraction of calcium-bound phosphate by Nat-EDTA at pH =
4.5. A comparison is made with two other sequential extraction procedures: the SEDEX and the Hieltjes & Lijklema extractions.
The EDTA extractions have an advantage over the other two methods. 相似文献
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Dr. Jan A. M. de Bont Annie Scholten Will J. J. van den Tweel 《Current microbiology》1985,12(5):267-271
The microbial potential to degrade acetylenic compounds (alkynes) was investigated, and several fungi and bacteria were isolated on 2-propyn-1-ol, 3-butyn-1-ol, propynoic acid, and 2-butyne-1,4-diol. The results indicate that a wide variety of microorganisms may degrade alkynes in nature. 相似文献
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Glasshouse evaluation of systemic compounds, derivatives of dithiocarbamic acid and other fungicides for the control of clubroot 总被引:1,自引:0,他引:1
Seventy-one fungicides were mixed with an artificially infested soil/peat mixture in which cabbage seedlings were subsequently grown in pots in a glasshouse. The incidence and severity of clubroot and any toxic effects on the plants were recorded. Carbendazim, chloraniformethan, maneb, ferbam, zinc N-methyl dithiocarbamate, zinc diethanolamine dithiocarbamate and ziram were selected as suitable for further evaluation as they gave disease control as good as the standard calomel treatment and were of comparably low phototoxicity. 相似文献
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Reaction of histamine with o-phthalaldehyde: isolation and analysis of the fluorophore 总被引:1,自引:0,他引:1
Histamine reacts with o-phthalaldehyde (OPT) to form colored as well as highly fluorescent derivatives. After large-scale synthesis, the chromophores were eliminated and the pale yellowish fluorophore was isolated by a series of chromatographic steps, followed by semipreparative high-performance liquid chromatography. Structural analysis of the fluorophore was performed using NMR and mass spectrometry. The isolated fluorophore was found to be a condensation product of 2 molecules of OPT and 1 molecule of histamine, arranged to form a complex dihydrophenantroline derivative with a quaternary amine group. The molecular weight of its chloride salt was 379.5. It was shown that the fluorophore exists in aqueous milieu as an equilibrium between three isomers. 相似文献