Syntheses, structures, catalytic and antitumor activities of a series of pyrimidine derivatives coordination complexes

Six pyrimidine derivatives based coordination complexes, namely, [Co(mpd)2(H2O)4]·2H2O (1), [Ni(mpd)2(H2O)4]·2H2O (2), [Co(hta)(H2O)3]·H2O (3), [Ni(hta)(H2O)3]·H2O (4), [Cu(Hhta)2(H2O)2]·3H2O (5) and [Zn(hta)(bpy)2]·2H2O (6) (Hmpd = 7-methylimidazo[1,2-a]- pyrimidine-2,5(1H,3H)-dione; H2hta = 2-(4-hydroxy-6-methylpyrimidin-2-ylthio) acetic acid; bpy = 4,4′-bipyridine) have been synthesized and characterized by elemental analysis, IR spectroscopy, PXRD, thermogravimetric analyses and X-ray crystallography. In the packing structures of the complexes, the hydrogen bonds (H-bonds) play important roles. The isomorphic complexes 1 and 2 show 3D tfz-d topology based on twelve H-bonds. Complex 3 and 4 are also isomorphic, exhibiting an unreported H-bonding 3D topology with 8H-bonds in the packing structure respectively. Complex 5 with fourteen H-bonds presents a H-bonding 3D new topology. {(H2O)4O2} H-bonding clusters in complex 6 link the coordination chains into a H-bonding 3D rtw topology. In addition, the catalytic properties of complex 1–6 are investigated. Compared with the other complexes, complex 5 exhibits the best catalytic performance in the decolorization of methyl blue (MB) and the oxidation of benzyl alcohol to benzaldehyde. Meanwhile, complex 5 also shows antitumor activity against HepG2 cells growth with an inhibition rate of 50.1%.