Synthesis, Spectral Characterization and Biological Activities of Co(II) and Ni(II) Mixed Ligand Complexes.

2,4-Dinitrophynylhydrazine and two thiocyanate ions in a (M:L1:L2) 1:2:2 molar ratio was synthesized in the complexes of Co(II) and Ni(II). The prepared compounds were identified through a C.H.N.S. analysis, conductivity measurements, powder X-ray diffraction (PXRD), the infrared spectrum, and a UV-visible spectrum analysis, in addition to the magnetic properties being measured. The measurements of the molar conductance implieda nonelectrolytic nature of compounds Co(II) and Ni(II). The magnetic susceptibility, as well as electronic spectra, represented all the metal complexesthroughoctahedral geometry, respectively. The PXRD patterns suggested that all the complexes were an orthorhombic system with unit cell parameters. The in-vitro biological activity of the ligand and the metal complexes were screened against the Gram-positive and negative pathogenic bacteria Staphylococcus aureus, Bacillus subtilis, Pseudomonas, aeruginosa and Escherichia coli, as well as the fungal species of Aspergillusniger and Candida albicans.Thus, the metal complexes showeda high efficiency of antimicrobial activity compared with the ligand. Furthermore, applications of the ligand, as well as the metal complexes, were tested for in-vitro antioxidant potential in aDPPH assay. The results showed that the activity of the metal complexes with the in-vitro antioxidant was more active than that of 2,4-dinitrophenylhydrazine(DNPH).

N,N'-Bis(3ß-acet-oxy-5α-cholest-6-yl-idene)hydrazine.

The asymmetric unit of the title compound, C(58)H(96)N(2)O(4), contains two crystallographically independent mol-ecules. All cyclohexane rings are in chair conformations, while the furan ring is in an envelope conformation in one mol-ecule and a twist conformation in the other. Two acetaldehyde and one isobutane groups are disordered over two orientations with refined site occupancies of 0.940 (4):0.060 (4) and 0.791 (7):0.209 (7), respectively. In the crystal, mol-ecules are stacked along the a axis through van der Waals inter-actions.

5-[(E)-(2-Hy-droxy-benzyl-idene)amino]-1H-1,3-benzimidazole-2(3H)-thione.

There are two mol-ecules in the asymmetric unit of the title compound, C(14)H(11)N(3)OS. In each, the benzimidazole ring system is essentially planar, with maximum deviations of 0.010 (2) and 0.006 (2) Å, and makes dihedral angles of 8.70 (9) and 13.75 (8)°, respectively, with the hy-droxy-substituted benzene rings. Each mol-ecule adopts an E configuration about the central C=N double bond. In the crystal, the two independent mol-ecules are connected via inter-molecular N-H⋯S hydrogen bonds, forming dimers. Furthermore, the dimers are connected by N-H⋯O hydrogen bonds into mol-ecular ribbons along the c axis. There is an intra-molecular O-H⋯N hydrogen bond in each mol-ecule, which generates an S(6) ring motif.

Synthesis, antibacterial and antifungal activities of 6,5 fused steroidal oxazoles in cholestane series.

Herein, we report a convenient one-pot synthesis of 2'-amino-5alpha-cholest-6-eno [6,5-d] oxazole derivatives (4-6). The synthesis involves the reaction of cholestan-6-ones (1-3) with urea and iodine. The structural assignment of the products was confirmed on the basis of IR, (1)H NMR, (13)C NMR, and Mass spectra which find support from comparison with authentic samples. The antibacterial activity of all the synthesized compounds was tested in vitro by the disk diffusion assay against three Gram-positive and three Gram-negative strains of bacteria. All the synthesized compounds were also tested for their inhibitory action against five strains of fungus and then the minimum inhibitory concentration (MIC) of all the synthesized compounds were determined. Compounds (4-6) showed inhibitory action against both types of the bacteria (Gram-positive and Gram-negative) and five strains of fungi are good antimicrobial agents. Chloramphenicol (30 microg) was used as standard drug in case of bacteria and nystatin was used as a standard drug in case of fungi.