Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysis, molar conductivity, infrared (IR) spectral analysis, atomic absorption spectroscopy (AAS) analysis, solubility test, and magnetic susceptibility. The Fourier-transform infrared spectroscopy (FTIR) spectral data of the Schiff base determined showed a band at 1622 cm −1 and this was assigned to the v (C=N), which is a feature of azomethine group. The same band was observed to shift to lower frequencies 1577 and 1599 cm −1 in the complexes suggesting coordination of the Schiff base with the respective metal(II) ions. Molar conductance values 14.58 and 12.65 Ω −1 •cm 2 •mol −1 show that the metal complexes were non-electrolyte in nature. The magnetic susceptibility of the complexes was determined and the gram magnetic susceptibility of the complexes was found to be positive, revealing that they are paramagnetic. The elemental analysis of the complexes for C, N and H determined suggested 1:1 metal to ligand ratio. The result of the antimicrobial studies showed that, the metal(II) complexes exhibited better antibacterial and antifungal activity than the Schiff base.

Manganese (II) complexes of Schiff bases; 2-acetylthiophene 4‑phenylthiosemi-carbazone (AT-PTSC) and 2-furylmethylketone-4-phenylthiosemi-carbazone (AF‑PTSC) derived from condensation of 2-acetylthiophene and 2-furylmethylketone (2-acetylfuran) each with 4-phenylthiosemicarbazide in (1:1 molar ratio) ethanol, have been synthesized. The Schiff bases and the Mn(II) complexes were characterized on the basis of melting point/decomposition temperature, solubility, magnetic susceptibility, infrared spectra, molar conductance measurements,  elemental and gravimetric  analyses. The Mn(II) complexes show moderate values of decomposition temperatures. The Schiff bases and the complexes were soluble in some common organic solvents. Infrared spectral data of the Schiff bases and their complexes, indicate coordination of the Schiff bases to the metal(II) ion via azomethine nitrogen. The effective magnetic moment of the Mn(II) complexes suggested an octahedral geometry. The molar conductance values of the complexes show that the complexes are electrolytes. The results of the elemental analysis of the ligands and their complexes are in good agreement with the calculated values, suggesting a 1:2 (metal-ligand) ratio. Antimicrobial screenings of the ligands and their complexes were conducted against gram-positive (Staphylococcus aureus,) and two gram-negative (Salmonella typhii, and Escherichia coli) bacteria specie. Also three fungi mainly (Candida albicans, Mucus indicus and Aspergillus flavus) were tested. The results showed that both the ligands and the complexes are active against the bacteria and the fungi specie. Keywords: Ligand, Schiff base, 4-phenylthiosemicarbazide, 2-acetylthiophene, 2-acetylfuran molar conductivity, magnetic susceptibility, elemental analysis.

The orthodox process of investigating lead molecules is a lengthy and laborious one that in most cases leads to minimal success. Molecular docking analysis provides an alternative path to drug discovery through the interactions of two or more complexes. Molecular docking studies were performed on 12 theoretically designed derivatives of 2’-substituted triclosan against a Plasmodium falciparum (P. falciparum) enoyl-acyl carrier protein reductase (PfENR) protein target as well as predicting their drug-likeness and SwissADME properties. The docking studies were carried out using the Molegro Virtual Docker (MVD) where the molecular interactions between the ligands and the target protein were studied. The docking analysis revealed 5-(((5-chloro-2-(4-chloro-2-hydroxyphenoxy)benzyl)amino)methyl) benzofuran-6-ol (re-rank docking score = -145.497 kcal/mol) as the most stable derivative. The compounds were all found to completely concord with the Lipinski rule regulations, in addition to the molar refractivity as well as the number of rotatable bonds appearing within acceptable limits. All compounds except 2–5 and 7 show high gastrointestinal absorption, and are non-inhibitors of cytochrome P450; CYP1A2 and CYP2C19 except CYP2C9, lack BBB penetration, and only compounds 2–7 and 12 were found to inhibit permeabilityglycoprotein (P-gp) substrate. The findings suggest that some of the derivatives tend to increase the oral bioavailability of the substrate and most of them cannot be used in the treatment of cerebral malaria. These results may lead to future optimisation of the designed derivatives for improved antimalarial agents.

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There were two ways used to synthesized cobalt (II) complexes of pyrazole by solid state. The first route involved direct reaction of the appropriate cobalt (II) acetate with pyrazole and pyrazolium chloride to form bispyrazole cobalt(II) salts, [(HPz)2CoCl2]. This was further ground in the second route with a two equivalents of a base (KOH) to make polymeric cobalt (II) pyrazolate [Co(Pz)2]. In all the synthesis above the ratio of ligand to cobalt (II) acetate was 2:1. All the cobalt (II) complexes were found to be of different colour from the starting materials and were characterized using solubility test, which showed that the complexes have poor solubility in most of the solvents used except in dimethylsulfoxide where they were soluble and the molar conductivity measurements of the complexes have low values (ranging from 6.44-6.45Ω-1cm2mol-1) which showed that they are non-electrolytes. The decomposition temperature showed that all the complexes have relatively low decomposition temperatures (93°C- 95°C). Characterization of the complexes via infrared analysis confirmed the coordination of metal with the ligand through pyridine-nitrogen and deprotonated-nitrogen in the range of 435.93cm-1 Co-N bonds and 406.99cm-1Co –N (for the route A and B respectively). The magnetic susceptibility measurements were carried out at room temperature and the effective magnetic moment values for all the complexes further confirmed complexation of the metal (II) ions with the ligand and also indicates that the cobalt (II) complexes are paramagnetic. The plot of absorbance against mole fraction in each case gives a curve with maximum absorbance corresponding to the ligand mole fraction used in calculating the number of coordinated ligands and 1:2 metal-ligand ratios were obtained in all the complexes. Keywords:  Mechanochemical, Pyrazole, Pyrazolate, Grinding, Mechanochemical Elimination.