Antitumor Activity Of Complexes Research Articles

Nucleic Acid Binding Behaviors and Cytotoxic Properties of a Ru(II) Complex

The interactions of complex [Ru(bpy)(2)(hnip)](2+) (1) {bpy = 2,2'-bipyridine, hnip = 2-(2-hydroxy-1-naphthyl)imidazo[4,5-f][1,10]phenanthroline} with calf thymus DNA and yeast tRNA were investigated by UV-vis spectroscopy, fluorescence spectroscopy, viscosity, equilibrium dialysis, and circular dichroism. In addition, the antitumor activities of complex 1 were evaluated with MTT method. These results indicate that the structures of DNA and RNA have significant effects on the binding behaviors of complex 1. Further, complex 1 demonstrates different antitumor activities against selected cancer cell lines in vitro.

Syntheses, structural characterizations and properties of 12-MC-4 organotin(IV) metallacrowns: [12-MC RSn(IV)N(shi)-4] and [12-MC RSn(IV)N(Clshi)-4] (R = Et, Bu, Ph; H 3shi = salicylhydroxamic acid; H 3Clshi = 5-chlorosalicylhydroxamic acid)

Five 12-MC-4 organotin(IV) metallacrowns(MCs) with the types of [12-MC RSn(IV)N(shi)-4] (R = Et ( 1), Bu ( 2), Ph ( 3); H 3Shi = salicylhydroxamic acid) and [12-MC RSn(IV)N(Clshi)-4] (R = Et ( 4), Bu ( 5), H 3Clshi = 5-chlorosalicylhydroxamic acid) have been synthesized and characterized by elemental analyses, IR and TGA. X-ray single-crystal diffraction analyses were also carried out and showed that all complexes 1– 5 contain a neutral 12-membered metallacrown ring which is formed by the succession of four repeating units of –[Sn–N–O]–, indicating the substituents on the tin(IV) atom are uninfluential in coordination of organotin(IV) centers with hydroxamic acid. Fluorescence properties of complexes 1– 5 have been investigated, where complex 3 displays strong fluorescence emissions in the blue region. In addition, antitumor activities of complexes 4 and 5 have also been tested, and both the complexes exhibit weak activity towards human hepatocellular carcinoma cell line (Bel-7402) and Hela cell line.

Synthesis, characterization and antitumor activity of new type binuclear platinum(II) complexes

Five new type binuclear platinum(II) complexes ( a– e) have been synthesized and characterized by elemental analysis, conductivity, thermal analysis, IR, UV, 1H NMR and mass spectral techniques. The cytotoxicity of the complexes was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and sulforhodamine B (SRB) assays. The acute toxicity and antitumor activity of complex e in vivo were also studied. The results indicate that complexes a– d have no activity against HL-60, MCF-7, BGC-823, EJ and HCT-8 cell lines, with a higher IC 50 value (>50 μM). Complex e confers substantially greater cytotoxicity against HL-60, MCF-7, BGC-823, EJ and HCT-8 cell lines with an IC 50 value of 0.02 ± 0.009, 1.70 ± 0.21, 4.00 ± 0.35, 0.98 ± 0.02 and 1.02 ± 0.21 μM, respectively. LD 50 of complex e is 815.3 mg/kg, it was significantly higher than that of cisplatin and carboplatin. Complex e at dose of 4, 12 and 20 mg/kg has no activity against mouse hepatocarcinoma H22 and Lewis lung carcinoma in mice, but displays significant activity against human ovarian carcinoma A2780 and human colon carcinoma HCT-116 in nude mice at dose of 12 mg/kg, and activity is similar to that of cisplatin at dose of 4 mg/kg. Complex e at dose of 20 mg/kg has no activity against human lung adenocarcinoma A549 in nude mice ( P > 0.05). The results suggest that the species of amine for the new type binuclear platinum complexes have important effect on their cytotoxicity, and they may be a new class platinum anticancer drugs.

Synthesis, Characterization and Antitumor Activity of Complexes of Lanthanide Nitrates with Bis(2-Pyridyl-N-Oxide) Disulfide

Complexes have been prepared from lanthanide nitrates and bis(2-pyridyl-N-oxide) disulfide (L) and characterized on the bases of elemental analyses, IR spectra, 1H NMR spectra, electronic spectra, fluorescence spectra and molar conductance. The ligand L acts only as an N-oxide oxygen donor resulting in the formation of 9-membered chelate rings. Preliminary results of in vitro tests on L1210 K562 cells show that all of them have antitumor activity.

Synthesis and antitumor activity of platinum complexes of protonated diamines

Complexes of the formula cis-[Pt(H N + ∼N)(L)Cl 2], where (H N + ∼N) are the protonated diamines including 3-aminoquinuclidine, N-aminopiperidine, piperazine, N-methylpiperazine, 1,1,4-trimethylpiperazine, and N-methyl-1,4-diazabicyclo [2,2,2] octane (N-methyl-dabco) and L = SCN −, NO 2 −, Br −, and F −, were synthesized from the protonated diamine complexes, [Pt(H N + ∼N)Cl 3]. The antitumor activities of the complexes were evaluated in vitro against L1210 murine leukemia cells, and ID 50 values for the L-substituted complexes were compared to values of the parent complexes. In each case it was found that replacement of a chloride ion by SCN −, NO 2 −, Br −, or F −, either reduced or completely eliminated antitumor activity. This effect is explained in terms of the trans-directing ability of the ligand, L, compared to chloride. The NO 2-substituted complex of 3- aminoquinuclidine was tested in vivo and found to exhibit little or no antitumor activity.