Five divalent transition metals Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) complexes have been synthesized using 3-hydroxy-4-[N-(2-hydroxynaphthylidene)-amino]-naphthalene-1-sulfonic acid (H3L) Schiff base as a ligand derived from the condensation reaction between 4-amino-3-hydroxynaphthalene-1-sulfonic acid and 2-hydroxy-1-naphthalde-hyde. The synthesized complexes were characterized using microanalytical, conductivity, FTIR, electronic, magnetic, ESR, thermal, and SEM studies. The microanalytical values revealed that the metal-to-ligand stoichiometry is 1:1 with molecular formula [M2+(NaL)(H2O)x].nH2O (where x = 3 for all metal ions except of Zn(II) equal x = 1; n = 4, 10, 7, 4, and 6 for Cu(II), Co(II), Ni(II), Mn(II) and Zn(II), respectively). The molar conductivity result indicates that all these complexes are neutral in nature with non-electrolytic behavior. Dependently on the magnetic, electronic, and ESR spectral data, octahedral geometry is proposed for all the complexes except to zinc(II) complex is tetrahedral. Thermal assignments of the synthesized complexes indicates the coordinated and lattice water molecules are present in the complexes. SEM micrographs of the synthesized complexes have a different surface morphologies. The antimicrobial activity data show that metal complexes are more potent than the parent ligand.
A series of thiazole derivatives were synthesized and structurally elucidated by IR, 1H NMR, 13C NMR, mass and elemental analyses. The prepared compounds were screened for their cytotoxic activity against Leukemia HL-60 cell line. Compound 4b was considered as the most promising antitumor candidate among the tested compounds. Mechanism of action of compound 4b evaluated by flow cytometric assay revealed cell cycle arrest at G2/M phase and pre-G1 apoptosis. The ratio of apoptosis was also determined. Moreover, compound 4b increased the concentration of caspase 3 by 4 fold more than untreated control.