Synthesis, characterization and antibacterial activity of aspirin and paracetamolmetal 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 havevaried degree of inhibitory effect against the bacteria

Fe (III) complex of mefloquine hydrochloride: Synthesis, antimicrobial and toxicological activities

As part of the ongoing research for more effective antimalarial drug, Fe (III) complex of mefloquine hydrochloride (antimalarial drug) was synthesized using template method. Mefloquine was tentativelyfound to have coordinated through the hydroxyl and the two nitrogen atoms in the quinoline and piperidine in the structure, respectively. Characterization has been done on the basis of analytical, conductance, atomic absorption, magnetic measurement, electronic and Infra-red spectrometry. From analytical data, the stoichiometry of the complex has been found to be 1:1. Infra-red spectral data also suggest that the ligand (mefloquine) behaves as a tridentate ligand with N:N:O donor sequencetowards the metal ion. On the basis of the above physico-chemical data it is proposed that the complex is assigned octahedral geometry. The antimicrobial activities of mefloquine metal complex exhibited greater inhibition than the parent ligand. The ligand and metal complex were screened for their toxicological activities at the dose of 6.66 mg/kg body weight twice daily for seven days on the alkaline phosphatase (ALP), alanine aminotranferase (ALT) and aspartate aminotransferase (AST) activities of rat serum, liver and kidney. Overall, it was revealed that both mefloquine and its metal complex might show mild toxicity particularly on the liver and kidney

Toxicological studies and antimicrobial properties of some Iron(III) complexes of Ciprofloxacin

Two iron(III) complexes of Ciprofloxacin were synthesized by reaction of the ligand with iron(III) chloride hexahydrate in different solutions. The nature of bonding of the ligands and the structure of the isolated metal complexes were elucidated on the basis of their physical and spectroscopic studies. The infrared spectra suggest that two classes of compounds were obtained: molecular complex in which the ligands were bidentately bonded to the metal through the ring carbonyl oxygen and one of the oxygen of the carboxylate group and the ionic complex consisting of a tetrachlorometalate ion which is electrostatically attached to the ligand. The antibacterial activities of the products against various microorganisms were tested and it was established that their activities were comparable with those of their parent drug. Toxicological studies were carried out in which therapeutic doses of the Ciprofloxacin drug and the metal complexes were administered to albino rats and the results showed that the metal complexes are not toxic

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 ± 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 cobaltlumefantrine metal complex. Serum alanine amino transferase, ALT (23.73 and 18.16 vs. 16.92 μg/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.Keywords: Antiplasmodial, metal-complex, rumen, sheep

Synthesis and biological studies of Co(II) and Cd(II) 5-(3,4,5- trimethoxybenzyl) pyrimidine-2,4-diamine (Trimethoprim) complexes

Two metal complexes of Co(II) and Cd(II) 5-(3,4,5-trimethoxybenzyl) pyrimidine-2,4-diamine (Trimethoprim) were synthesized and characterized by both analytical and spectroscopic methods. They are 4-coordinate complex containing two molecules of 5-(3,4,5-trimethoxybenzyl) pyrimidine-2,4-diamine (TMP) and two chloride ions. A distorted tetrahedral geometry is suggested for their structure, where TMP behaves as a monodentate ligand. The metal binds through the pyrimidine N(1) of the ligand. The complexes have been screened for antiplasmodial activity against Plasmodium berghei and the results show that they are less active than the parent ligand. Toxicological study was carried out by investigating the effect of administration of the complexes on alkaline phosphatase activity of kidney, liver and serum of albino rats and they are found to be nontoxic

Relative Availability of Nickel in the Goat

A study was carried out to compare the rates of absorption of nickel from two nickel complexes and two nickel salts in the West African Dwarf (WAD) goat. Treatments consisted of oral administration of 5mg equivalents of elemental nickel from nickel sulphate hexahydrate (NiSO4.6H2O); nickel chloride hexahydrate (NiCl2.6H2O); nickel sodium monofluorophosphate (Ni-SMFP) complex and nickel-chloroquine (Ni-Clrq) complex. Changes in the plasma levels of nickel were monitored until the concentration declined. Nickel absorption into the blood was in the order: Ni-SMFP>NiClrq>NiSO4.6H2O>NiCl2.6H2O indicating that nickel is more readily available to goats in the complex forms. JARD Vol. 1 2001: pp. 23-3