Synthesis, characterization and antitumor activities in vitro of Cu-based complexes of pyrimidine derivative salicylaldehyde Schiff bases

Abstract

Copper-based complexes synthesized from pyrimidine derivative Schiff base ligands play an important role in the fields of biology and medicine because they possess diverse biological activities like antitumor and antibacterial etc. Herein, we constructed six bioactive Cu-based complexes, namely, [Cu(HL1)0.49(HCL1)0.51(H2O)] (1), [Cu(HL2)0.46(HCL2)0.54(H2O)]·(H2O) (2), [Cu(HL3)0.49(HCL3)0.51(H2O)]·(H2O) (3), [Cu(HL4)0.52(HCL4)0.48(H2O)]·(H2O) (4), [Cu(HL5)0.42(HCL5)0.58(MeOH)] (5), [Cu(HL6)0.49(HCL6)0.51(H2O)(MeOH)]·(NO3) (6), using pyrimidine derivatives salicylaldehyde Schiff base ligands as raw materials. X-ray single crystal diffraction, elemental analysis, X-ray powder diffraction, and infrared spectroscopy were used to characterize the synthesized compounds. Using the MTT assay, the in vitro anti-tumor cell proliferation efficacy of ligands and complexes against Human Hepatoma cells (HepG2, BEL-7404), Human Cervical Cancer Cells (HeLa) and Human Normal Liver cells (HL-7702). The findings showed that 3 had more anticancer efficacy than other compounds. Moreover, it is important to note that the inhibitory rate and in vitro cytotoxicity (IC50) of 3 on cancer cells and normal cells tested were significantly better than cisplatin, showing the universality of anti-tumor. In addition, 1 and 4 exhibited a particular selectivity to HeLa, while the analysis results of 2 also showed universality of anti-tumor.