A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(...A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), or Gd(Ⅲ) and HAAP=3-{[2-(N-1-phenyl-2,3-dimethylpyrazol-3-in-5-on-4-yl)]hydrazone}pent-2,3,4-trione. The ligand and metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, infrared, far infrared and proton NMR spectral data. The spectral data revealed that the ligand existed in the hydrazo form and coordinated to the metal ion without deprotonation in a neutral tridentate manner, through carbonyl oxygen of pyrazolone ring, hydrazo nitrogen and carbonyl oxygen of the acetylace-tone moiety. The molar conductance values adequately supported their non-electrolytic nature. The ligand and the praseodymium(Ⅲ) complex were subjected to X-ray diffraction studies. Thermal decomposition behavior of the lanthanum(Ⅲ) complex was also examined.展开更多
The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine （CI7H16N4O 1） and its perchlorate （C17H17N4O·ClO4 2） have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray...The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine （CI7H16N4O 1） and its perchlorate （C17H17N4O·ClO4 2） have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820（12）, b = 24.934（3）, c = 7.0064（10） A,, β= 97.942（3）°, V = 1502.2（4） A^3, Z = 4, Dc = 1.293 g/cm^3, F（000） = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302（2）, b = 20.347（7）, c = 14.663（6） A, β= 90.200（9）°, V= 1769.201） A^3, Z = 4, Dc = 1.475 g/cm^3, F（000） = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N（1） of pyridine-2-carboxaldehyde-4- aminoantipyrine.展开更多
A multi-walled carbon nanotube （MWCNT）-cetyltrimethylammonium bromide （CRAB） surfactant com- posite modified glassy carbon electrode （GCE） was developed as a novel system for the determination of 4-aminoantipyr...A multi-walled carbon nanotube （MWCNT）-cetyltrimethylammonium bromide （CRAB） surfactant com- posite modified glassy carbon electrode （GCE） was developed as a novel system for the determination of 4-aminoantipyrine（AAP）. The oxidation process was irreversible over the pH range studied and exhibited a diffusion controlled behavior. All experimental parameters were optimized. The combination of MWCNT-CRAB endows the biosensor with large surface area, good biological compatibility, electricity and stability, high selectivity and sensitivity. MWCNT-CTAB/GCE electrode gave a linear response for AAP from 5.0 x 10-9 to 4.0 x 10-8 M with a detection limit of 1.63 x 10 lo M. The modified electrode showed good selectivity against interfering species and also exhibited good reproducibility. The present elec- trochemical sensor based on the MWCNT-CFAB/GCE electrode was applied to the determination of AAP in real samples.展开更多
Various compounds of 4-aminoantipyrine Schiff bases(M1–M12) were synthesized via a condensation reaction of 4-aminoantipyrine with different benzaldehydes through a conventional method of refluxing the mixture for 3...Various compounds of 4-aminoantipyrine Schiff bases(M1–M12) were synthesized via a condensation reaction of 4-aminoantipyrine with different benzaldehydes through a conventional method of refluxing the mixture for 3–4 h. The synthesized Schiff bases were characterized by using elemental analyses, FT-IR, UV-Vis, Mass, 1 H and 13 C NMR spectroscopy. The antimicrobial activity of the synthesized Schiff bases was investigated against 12 bacterial strains(Mycobacterium smegmatis, Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Staphylococcus epidermidis, Klebsiella pneumonia, Escherichia coli, Enterobacter cloacae, Klebsiella oxytoca, Proteus vulgaris, Enterobacter aerogenes, and Pseudomonas aeruginosa), and antifungal activities were tested against seven fungal strains(Aspergillus flavus, Aspergillus carbonarious, Aspergillus parasiticus, Aspergillus fumigatus, Aspergillus niger, Fusarium verticillioides and Fusarium proliferatum). The antimicrobial activities of the synthesized compounds were compared with standard streptomycin and nalidixic acid. The results obtained from antibacterial assay indicated that M1–M12 inhibited potential growth of Proteus vulgaris with minimum inhibitory concentrations(MICs) ranging from 15.6–250 μg/mL compared with the standard nalidixic acid with an MIC of 500 μg/mL. Moreover, we could conclude that most of the tested compounds experienced mild to low activities at 15.6 μg/mL. Their activities could be attributed to their low concentration s. The antifungal analysis showed that the tested fungi were not sensitive to the prepared Schiff bases at the prepared concentration of 500 μg/mL. Therefore, we recommended further analysis on both cytotoxicity and minimum bactericidal concentration(MBC) to ascertain their potential effects against human cells.展开更多
文摘A heterocyclic ligand synthesized by the coupling of diazotized 4-aminoantipyrine with acetylacetone reacted with lanthanide(Ⅲ) nitrate to form complexes of the type [Ln(HAAP)2(NOз)з] where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), or Gd(Ⅲ) and HAAP=3-{[2-(N-1-phenyl-2,3-dimethylpyrazol-3-in-5-on-4-yl)]hydrazone}pent-2,3,4-trione. The ligand and metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV-Visible, infrared, far infrared and proton NMR spectral data. The spectral data revealed that the ligand existed in the hydrazo form and coordinated to the metal ion without deprotonation in a neutral tridentate manner, through carbonyl oxygen of pyrazolone ring, hydrazo nitrogen and carbonyl oxygen of the acetylace-tone moiety. The molar conductance values adequately supported their non-electrolytic nature. The ligand and the praseodymium(Ⅲ) complex were subjected to X-ray diffraction studies. Thermal decomposition behavior of the lanthanum(Ⅲ) complex was also examined.
基金supported by the NSF of Guangxi Province (No. 0575046, 0575049)the Program for New Century Ten-Hundred-Thousand Excellent Talents of Guangxi (No. 2003223)+1 种基金the National Natural Science Foundation of China (No. 20361002, 30460153) as well as TRAPOYTNCET-04-0836 of Chinese Ministry of Education
文摘The Schiff base pyridine-2-carboxaldehyde-4-aminoantipyrine （CI7H16N4O 1） and its perchlorate （C17H17N4O·ClO4 2） have been prepared and characterized by elemental analysis, IR spectra and single-crystal X-ray crystallography analysis. Both 1 and 2 crystallize in the monoclinic system, space group P21/c. For 1, a = 8.6820（12）, b = 24.934（3）, c = 7.0064（10） A,, β= 97.942（3）°, V = 1502.2（4） A^3, Z = 4, Dc = 1.293 g/cm^3, F（000） = 616,μ = 0.084 mm^-1, the final R = 0.0592 and wR = 0.1244. For 2, a = 5.9302（2）, b = 20.347（7）, c = 14.663（6） A, β= 90.200（9）°, V= 1769.201） A^3, Z = 4, Dc = 1.475 g/cm^3, F（000） = 816, μ = 0.254 mm^-1, the final R = 0.0533 and wR = 0.0819. As expected, both molecular structures of 1 and 2 adopt a trans configuration about the central C=N double bond. 2 is an ionic compound with the protonation at N（1） of pyridine-2-carboxaldehyde-4- aminoantipyrine.
文摘A multi-walled carbon nanotube （MWCNT）-cetyltrimethylammonium bromide （CRAB） surfactant com- posite modified glassy carbon electrode （GCE） was developed as a novel system for the determination of 4-aminoantipyrine（AAP）. The oxidation process was irreversible over the pH range studied and exhibited a diffusion controlled behavior. All experimental parameters were optimized. The combination of MWCNT-CRAB endows the biosensor with large surface area, good biological compatibility, electricity and stability, high selectivity and sensitivity. MWCNT-CTAB/GCE electrode gave a linear response for AAP from 5.0 x 10-9 to 4.0 x 10-8 M with a detection limit of 1.63 x 10 lo M. The modified electrode showed good selectivity against interfering species and also exhibited good reproducibility. The present elec- trochemical sensor based on the MWCNT-CFAB/GCE electrode was applied to the determination of AAP in real samples.
基金supported by the Faculty of Science,Department of Applied Chemistrythe University of Johannesburg for providing enabling environment to perform this workthe National Research Foundation(NRF)for the provision of running cost of this work
文摘Various compounds of 4-aminoantipyrine Schiff bases(M1–M12) were synthesized via a condensation reaction of 4-aminoantipyrine with different benzaldehydes through a conventional method of refluxing the mixture for 3–4 h. The synthesized Schiff bases were characterized by using elemental analyses, FT-IR, UV-Vis, Mass, 1 H and 13 C NMR spectroscopy. The antimicrobial activity of the synthesized Schiff bases was investigated against 12 bacterial strains(Mycobacterium smegmatis, Bacillus cereus, Bacillus subtilis, Enterococcus faecalis, Staphylococcus epidermidis, Klebsiella pneumonia, Escherichia coli, Enterobacter cloacae, Klebsiella oxytoca, Proteus vulgaris, Enterobacter aerogenes, and Pseudomonas aeruginosa), and antifungal activities were tested against seven fungal strains(Aspergillus flavus, Aspergillus carbonarious, Aspergillus parasiticus, Aspergillus fumigatus, Aspergillus niger, Fusarium verticillioides and Fusarium proliferatum). The antimicrobial activities of the synthesized compounds were compared with standard streptomycin and nalidixic acid. The results obtained from antibacterial assay indicated that M1–M12 inhibited potential growth of Proteus vulgaris with minimum inhibitory concentrations(MICs) ranging from 15.6–250 μg/mL compared with the standard nalidixic acid with an MIC of 500 μg/mL. Moreover, we could conclude that most of the tested compounds experienced mild to low activities at 15.6 μg/mL. Their activities could be attributed to their low concentration s. The antifungal analysis showed that the tested fungi were not sensitive to the prepared Schiff bases at the prepared concentration of 500 μg/mL. Therefore, we recommended further analysis on both cytotoxicity and minimum bactericidal concentration(MBC) to ascertain their potential effects against human cells.
