Objective： A series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipophilic naphthalene ring to render them more capable of penetrating various biomembranes. Methods： Schiff ...Objective： A series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipophilic naphthalene ring to render them more capable of penetrating various biomembranes. Methods： Schiff bases were synthesized by the reaction of naphtha[1,2-d]thiazol-2-amine with various substituted aromatic aldehydes. 2-（2＇-Hydroxy）ben- zylideneaminonaphthothiazole was converted to its Co（Ⅱ）, Ni（Ⅱ） and Cu（Ⅱ） metal complexes upon treatment with metal salts in ethanol. All the compounds were evaluated for their antibacterial activities by paper disc diffusion method with Gram positive Staphylococcus aureus and Staphylococcus epidermidis and Gram negative Escherichia coli and Pseudomonas aeruginosa bacteria. The minimum inhibitory concentrations of all the Schiff bases and metal complexes were determined by agar streak dilution method. Results： All the compounds moderately inhibited the growth of Cram positive and Gram negative bacteria. In the present study among all Schiff bases 2-（2＇-hydroxy）benzylideneaminonaphthothiazole showed maximum inhibitory activity and among metal complexes Cu（Ⅱ） metal complex was found to be most potent. Conclusion： The results obtained validate the hypothesis that Schiff bases having substitution with halogens, hydroxyl group and nitro group at phenyl ring are required for the antibacterial activity while methoxy group at different positions in the aromatic ring has minimal role in the inhibitory activity. The results also indicated that the metal complexes are better antibacterial agents as compared to the Schiff bases.展开更多
In this research two chromium（II][） and （VI） complexes of tetradentate Schiff bases have been prepared by condensing of salicylaldehyde with 4-methyl 1,2-phenylenediamine. Schiff base complexes of chromium（Ill） ...In this research two chromium（II][） and （VI） complexes of tetradentate Schiff bases have been prepared by condensing of salicylaldehyde with 4-methyl 1,2-phenylenediamine. Schiff base complexes of chromium（Ill） have been employed to design and synthesize polynuclear complexes. So they have played an important role in molecular magnetism. Synthesized complexes were characterized by elemental analysis, IR, molar conductivity and NMR. The free ligands were alsc characterized by 1H, 13C NMR spectra. The 13C NMR and IR spectra of free ligand and the complexes are compared and discussed.展开更多
Four cyanide-bridged heterometallic complexes { [CuPb（L1）][FenI（bpb）（CN）2] }2-（C104）2.2H20.2CH3CN （1）, { [CuPb（LI）]2[FeII （CN）6]（HzO）z}＇10H20 （2）, {[Cu2（L2）][Fent（bpb）（CN）2]2}＇2H20＇2CH3OH （...Four cyanide-bridged heterometallic complexes { [CuPb（L1）][FenI（bpb）（CN）2] }2-（C104）2.2H20.2CH3CN （1）, { [CuPb（LI）]2[FeII （CN）6]（HzO）z}＇10H20 （2）, {[Cu2（L2）][Fent（bpb）（CN）2]2}＇2H20＇2CH3OH （3） and {[Cu2（L2）]3[FeIII（CN）6]z（H20）2}-10H20 （4） have been synthesized by treating K[Fem（bpb）（CN）2] [bpb2-=l,2-bis（pyridine-2-carboxamido）benzenate] and K3[Feln（CN）]6 with dinuc[ear compartmental macrocyclic Schiff-base complexes [CuPh（LI）].（C104）2 or [Cu2（L2）]-（CIO4）2, in which H2LJ was derived from 2,6-diformyl-4-methyl-phenol, ethylenediamine, and diethylenetriamine in the molar ratio of 2：1：1 and H2L2 from 2,6-diformyl-4-methyl-phenol and propylenediamine in the molar ratio of 1：1. Single crystal X-ray diffraction analysis reveals that compound 1 displays a cyclic hexanuclear heterotrimetallic molecular structure with alternating [Fem（bpb）（CN）2]- and [CuPb（L＋）]2＋ units. Complex 2 is of a neutral dumb-bell-type pentanuclear molecular configuration consisting of one [Fe（CN）6]4- anion sandwiched in two [CuPu（L1）]2＋ cations, and the pentanuclear moieties are further connected by the hydro- gen bonding to give a 2D supramolecular framework. Heterobimetallic complex 3 is a tetranuclear molecule composed of a centrosymmetric [Cuz（L2）]2＋ segment and two terminal cyanide-containing blocks [Fetn（bpb）（CN）2]-. Octanuclear compound 4 is built from two [Fe（CN）6]3- anions sandwiched in the three [Cu2L2]2＋ cations. Investigation of their magnetic properties reveals the overall antiferromagnetic behavior in the series of complexes except 2.展开更多
文摘Objective： A series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipophilic naphthalene ring to render them more capable of penetrating various biomembranes. Methods： Schiff bases were synthesized by the reaction of naphtha[1,2-d]thiazol-2-amine with various substituted aromatic aldehydes. 2-（2＇-Hydroxy）ben- zylideneaminonaphthothiazole was converted to its Co（Ⅱ）, Ni（Ⅱ） and Cu（Ⅱ） metal complexes upon treatment with metal salts in ethanol. All the compounds were evaluated for their antibacterial activities by paper disc diffusion method with Gram positive Staphylococcus aureus and Staphylococcus epidermidis and Gram negative Escherichia coli and Pseudomonas aeruginosa bacteria. The minimum inhibitory concentrations of all the Schiff bases and metal complexes were determined by agar streak dilution method. Results： All the compounds moderately inhibited the growth of Cram positive and Gram negative bacteria. In the present study among all Schiff bases 2-（2＇-hydroxy）benzylideneaminonaphthothiazole showed maximum inhibitory activity and among metal complexes Cu（Ⅱ） metal complex was found to be most potent. Conclusion： The results obtained validate the hypothesis that Schiff bases having substitution with halogens, hydroxyl group and nitro group at phenyl ring are required for the antibacterial activity while methoxy group at different positions in the aromatic ring has minimal role in the inhibitory activity. The results also indicated that the metal complexes are better antibacterial agents as compared to the Schiff bases.
文摘In this research two chromium（II][） and （VI） complexes of tetradentate Schiff bases have been prepared by condensing of salicylaldehyde with 4-methyl 1,2-phenylenediamine. Schiff base complexes of chromium（Ill） have been employed to design and synthesize polynuclear complexes. So they have played an important role in molecular magnetism. Synthesized complexes were characterized by elemental analysis, IR, molar conductivity and NMR. The free ligands were alsc characterized by 1H, 13C NMR spectra. The 13C NMR and IR spectra of free ligand and the complexes are compared and discussed.
基金financially supported by the National Natural Science Foundation of ChinaMinistry of Education of China+1 种基金Beijing Municipal Commission of EducationFundamental Research Funds for the Central Universities
文摘Four cyanide-bridged heterometallic complexes { [CuPb（L1）][FenI（bpb）（CN）2] }2-（C104）2.2H20.2CH3CN （1）, { [CuPb（LI）]2[FeII （CN）6]（HzO）z}＇10H20 （2）, {[Cu2（L2）][Fent（bpb）（CN）2]2}＇2H20＇2CH3OH （3） and {[Cu2（L2）]3[FeIII（CN）6]z（H20）2}-10H20 （4） have been synthesized by treating K[Fem（bpb）（CN）2] [bpb2-=l,2-bis（pyridine-2-carboxamido）benzenate] and K3[Feln（CN）]6 with dinuc[ear compartmental macrocyclic Schiff-base complexes [CuPh（LI）].（C104）2 or [Cu2（L2）]-（CIO4）2, in which H2LJ was derived from 2,6-diformyl-4-methyl-phenol, ethylenediamine, and diethylenetriamine in the molar ratio of 2：1：1 and H2L2 from 2,6-diformyl-4-methyl-phenol and propylenediamine in the molar ratio of 1：1. Single crystal X-ray diffraction analysis reveals that compound 1 displays a cyclic hexanuclear heterotrimetallic molecular structure with alternating [Fem（bpb）（CN）2]- and [CuPb（L＋）]2＋ units. Complex 2 is of a neutral dumb-bell-type pentanuclear molecular configuration consisting of one [Fe（CN）6]4- anion sandwiched in two [CuPu（L1）]2＋ cations, and the pentanuclear moieties are further connected by the hydro- gen bonding to give a 2D supramolecular framework. Heterobimetallic complex 3 is a tetranuclear molecule composed of a centrosymmetric [Cuz（L2）]2＋ segment and two terminal cyanide-containing blocks [Fetn（bpb）（CN）2]-. Octanuclear compound 4 is built from two [Fe（CN）6]3- anions sandwiched in the three [Cu2L2]2＋ cations. Investigation of their magnetic properties reveals the overall antiferromagnetic behavior in the series of complexes except 2.
