Divalent metal complexes of 4-amino-N-pyrimidin-2-ylbenzene sulphonamide and their antimalarial activities against Plasmodium berghei

Coordination compounds of 4-amino-N-pyrimidin-2-ylbenzene sulphonamide (APS) were synthesized. The complexes were formulated as [Co(APS)2(H2O)2], [Cu(APS)2(H2O)2], [Ni(APS)2(H2O)2], [Cd(APS)2](H2O)2, [Fe(APS)3](H­2O)­3 and [Mn(APS)2(H2O)2] characterized by elemental analysis, conductivity, IR, UV-Vis, magnet moment and 1H-NMR and mass spectroscopies. In all the complexes the metal ions coordinate through pyrimidinic nitrogen and sulphonamidic nitrogen of the two molecules of APS. The suggested structure for Cd(II) complex of APS is tetrahedral, while that of Cu(II), Mn(II) and Ni(II) APS complexes is octahedral. The inner coordination spheres were occupied by two water molecules in Co(II), Mn(II), Cu(II), Ni(II) APS complexes except Cd(II) with 2 molecules of  water outside the coordination  sphere. Fe(III) coordinates with 3 molecules of APS with 3 molecules of water outside the coordination sphere. The antiparasitic studies using Plasmodium berghei as test organism showed that the Fe(III) complex exhibits higher activity than chloroquine and  ligand. All other complexes have lower antiparasitic activity.KEY WORDS: Sulphonamide, Antimalarial activity, Plasmodium berghei Bull. Chem. Soc. Ethiop. 2011, 25(3), 371-380

Synthesis, Characterization And Antibacterial Activity Of Aspirin And Paracetamol-metal Complexes

Novel complexes of Co (11), Ni (11) and Fe (111) with aspirin and paracetamol have synthesized and characterized using infrared, electronic and Hnmr spectral, melting point and conductivity measurements. The two ligands have been found to act as bidentate chelating agents. Aspirin complexes coordinate through the carbonyl oxygen of the carboxyl and the ester groups, while paracetamol complexes coordinate through the oxygen of the hydroxyl and the amide groups. Antibacterial screening of the complexes against Bacillus substilis , serratia species and Escherichia coli , was also investigated. The metal complexes were found to have varied degree of inhibitory effect against the bacteria

Antimalarial and Antimicrobial Activities of some Heteroleptic Metal(II) Complexes of Sulfadiazine–Vitamin C: Synthesis and Spectroscopic Studies

Some new Ni(II), Zn(II), Co(II), Cu(II), and Cd(II) of mixed Sulphadiazine and Vitamin C complexes have been synthesized and characterized by different spectroscopic techniques such as FT-IR, elemental analysis, molar conductivity, and magnetic measurements. Both ligands used for this research work act as bidentate ligands towards the central metal ions coordinating through the nitrogen atoms of >C=N-, NH2 groups of Sulphadiazine and oxygen atoms of OH, CO groups of Vitamin C. Tetrahedral and square-planar geometries have been proposed for the complexes. The complexes are stable under atmospheric conditions. The ligands and their complexes were screened for antimicrobial activities against some isolated organisms: Klebsiella pneumoniae, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis to evaluate their microbial inhibiting potential. The derived complexes were found to exhibit an increased inhibitory action against the organisms when compared to the free ligands. The percentage reduction in parasitaemia for the compounds was also evaluated against Plasmodium berghei. In this realm, [Cd(Su)(Vit)]Cl2 showed the highest activity (89%) as compared to other compounds: Sulphadiazine, Ni(II), Zn(II), Co(II), and Cu(II) complexes are 70, 50, 81, 76, and 77%, respectively, Vitamin C showed no activity. Keywords: Sulfadiazine, Antimalarial, Vitamin C, Physicochemical, Metal-drug complexes, Antimicrobia

Preparation, Characterization, and Antimicrobial Activities of Mixed Ibuprofen-Salicylic Acid Metal-Drug Complexes

Most variants of bacteria are resistant to traditional antibiotics which are organic. To overcome the growing infections, bacteria resistant infections, and multiple drug resistance (MDR) rates, transition metals with biological importance were coordinated to organic ligands (Ibuprofen and Salicylic acid) with anti-inflammatory properties. In this study, metal complexes of mixed Ibuprofen and Salicylic acid were prepared using a standard method to give of the type [M(Ibu)(Sal)X] (where M = Fe2+, Ni2+, Cu2+, and X = Cl2, Ibu = Ibuprofen, Sal = Salicylic acid). The complexes were characterized by UV-visible spectroscopy, conductivity measurements, melting points, FT-IR, and X-ray diffraction. The metal ions are coordinated to the ligands via the carboxylato oxygen donor atoms of both ligands. From the physicochemical data, the complexes are non-electrolytes. The XRD study suggested that the metal complexes possess a well-defined crystalline structure with average crystallite sizes of < 62 nm. Evaluations of the antimicrobial activities of the ligands and their complexes against gram-positive bacteria (S. aureus, B. subtilis,  S. faecalis) and gram-negative bacteria (K. pneumonia, E. coli, and  P. aeroginosa) via standard method were utilized to determine the zones of inhibition. The complexes exhibited a higher zone of inhibition, indicating higher antimicrobial activities when compared to the parent ligand. The results revealed that the metal-drug complexes are promising chemotherapeutic agents with wide spectrum of activities. Keywords:  Metal-drug complexes; Ibuprofen; Spectra studies; Salicylic acid; Antimicrobial activit

Perception and Resistance Mechanism of some Metal-drug Complexes and Their Roles as Antibacterial

Metal-based drugs have undergone much development and application for therapeutic and diagnostic purposes for many decades since the huge success of cisplatin and other successful metal-drug complexes in the clinical stages. Furthermore, this metal-based drug has come up with a lot of signs of resistance and side-effects in their uses. This review points to some of the resistance natures and mechanisms of previously synthesized complexes in the field of chemistry

Influence of Anti-Plasmodial Metal Complex on Rumen Microbial Populations and Serum Parameters in Sheep

A locally synthesized transition metal complex, cobalt-lumefantrine was assessed through laboratory and feeding trials to ascertain its usefulness as an agent for manipulation of the rumen in sheep grazing tropical pasture. The antimicrobial properties of the metal complex were examined on fresh rumen fluids at different concentrations (0, 0.010, 0.025 and 0.050 mg metal complex/50 ml) to estimate the optimum dosage for the sheep. Thereafter, twelve adult male sheep (11.27 \ub1 0.62 kg, initial body weight) were divided into three similar treatment groups. Sheep were drenched individually with 2.5 mg metal complex/head dissolved in 10 ml distilled water, either once or at two-week interval over 28 days. The control group received water without the metal complex. Total protozoa population was lowest (P < 0.05) when 50 ml rumen sample was incubated with 0.025 mg cobalt-lumefantrine metal complex. Serum alanine amino transferase, ALT (23.73 and 18.16 vs. 16.92 \ub5g/L) and cholesterol (0.94 and 1.18 vs. 1.40 mmol/L) levels were significantly (P < 0.05) influenced by the antiplasmodial metal complex treatments (single and repeated treatments vs. the control). It was concluded that 2.5 mg cobalt-lumefantrine complex treatment had no adverse effects on rumen pH, favourably modified rumen microbial populations and improved serum cholesterol level in the sheep

Synthesis, Characterization And Antibacterial Activity Of Aspirin And Paracetamol-metal Complexes

Novel complexes of Co (11), Ni (11) and Fe (111) with aspirin and paracetamol have synthesized and characterized using infrared, electronic and Hnmr spectral, melting point and conductivity measurements. The two ligands have been found to act as bidentate chelating agents. Aspirin complexes coordinate through the carbonyl oxygen of the carboxyl and the ester groups, while paracetamol complexes coordinate through the oxygen of the hydroxyl and the amide groups. Antibacterial screening of the complexes against Bacillus substilis , serratia species and Escherichia coli , was also investigated. The metal complexes were found to have varied degree of inhibitory effect against the bacteria

Synthesis, characterization and antibacterial susceptibility testing of manganese complexes of doxycyline with bipyridine and phenanthroline

Three manganese complexes of the antibiotic doxycyline viz.: manganese doxycyline, [MnDox2]Cl2‧2H2O (1), and manganese doxycyline with bipyridine, [MnDox2(bpy)]Cl2‧8H2O (2), and phenanthroline, [MnDox2(phen)]Cl2‧8H2O (3), as the ancillary ligand were synthesized and characterized by FT-IR, elemental analysis and electrospray mass spectroscopy. The three complexes show good solubility in DMF and DMSO. Data obtained from spectroscopic techniques used show that doxycycline coordinates to the central manganese atom through the oxygen of the amide group and the carbonyl oxygen atom of ring A while bipyridine/phenanthroline coordinates through the two diimine nitrogen atoms. The stoichiometry of manganese-doxycycline is 1:2 and octahedral geometry is the preferred coordination in all the complexes