Synthesis, Characterization, DNA Binding and Cytotoxic Studies of Platinum(II) and Palladium(II) Complexes of the 2,2'-Bipyridine and an Anion of 1,1-Cyclobutanedicarboxylic Acid.

2008

Following the discovery of cis-diamminedichloroplatinum(II) (cisplatin) as the successful antitumor drug, 1) the research of the design and synthesis of novel platinum(II) complexes, having more favorable antitumor activities as compared with cisplatin, has been continued. [2][3][4][5] Palladium(II) complexes have been also investigated for developing the new antitumor agents, [6][7][8][9][10][11][12] because palladium(II) has a similar coordination mode and chemical properties to platinum(II).12) As the result, several novel palladium(II) complexes having antitumor citotoxic activities against MCF-7, TK-10 and UACC-62 human tumor cell lines, 13) and P388 lymphocytic leukemia cells have been found. [14][15][16][17] In these complexes, the ternary palladium(II) complexes with a heterocyclic ligand and L-glycine one, [Pd(Gly)(X)] (where X is a heterocyclic ligand; 2,2Ј-bipyridylamine(bpa), 15) 1,10-phenanthroline (phen) 16) and 2,2Ј-bipyridine(bpy) 17) ) have the antitumor activity against P388 lymphocytic leukemia cells. At the present time, the structures of these complexes are not yet clear, although they are important for clarifying the mechanism of their antitumor activity. By these circumstances, in this study, our aim was to determine the structures of three ternary Pd(II) complexes, [Pd(Gly)(bpy)], and evaluate the interaction with DNA, which is one of targets in the chemotherapy of tumor. 18) ExperimentalMaterials Analytical grade of 2,2Ј-bipyridine (bpy), 1,10-phenanthroline (phen), and 2,2Ј-bipyridylamine (bpa), L-glycine Methods The X-ray measurements were performed on a Rigaku R-AXIS RAPID diffractometer with a graphite monochromatized MoKa radiation (lϭ0.71069 Å) using the w scan mode at 123.1 K.Fluorescence measurements were performed with a Hitachi 850 spectrofluorometer. UV measurements were made on a Shimazu Pharma Spec UV-1700 Spectrophotometer and CD measurements on a JASCO J-710 CD spectrophotometer. The agarose gel electrophoresis was performed using a COSMO BIO Mupid-2. Elemental analysis was done by using a YANACO CHN Coder MT-3.Preparation of the Complexes The complex 1, 2 and 3 were prepared according to the analogous method described previously. 15,19) 0.76 mmol of bpy, phen or bpa were mixed with 0.76 mmol of PdCl 2 · 2NaCl · 3H 2 O in 5 ml of 80% (v/v) methanol-water solution for about 5 min at room temperature. The precipitates appeared after adding palladium salt. Each precipitate was dried under a vacuum and assumed as [Pd(bpy)Cl 2 ], [Pd(phen)Cl 2 ] and [Pd(bpa)Cl 2 ]. Then, 0.015 mmol of the precipitate was reacted with equal moles of Gly and NaHCO 3 in 5 ml of water solution for about 1 h at 333-343 K, until the volume of the reaction mixture was concentrated to ca. 1 ml. The concentrated solution was allowed to stand at room temperature for slow evaporation. Two weeks later, the light yellow needle crystals of the complex 1 and 3 suitable for X-ray diffraction studies were obtained from the mother liquid, and three months later the brown needle crystal of the complex 2 was obt...

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confidence: 99%

Structures and Interaction with DNA of Ternary Palladium(II) Complexes: [Pd(Gly)(X)] (Gly=Glycine; X=2,2′-Bipyridine, 1,10-Phenanthroline and 2,2′-Bi-pyridylamine)

Yodoshi

2008

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“…4) Even the principle mechanism of its antitumor property is not known, it is known that some kinds of the aromatic heterocycles can stack with nucleobases and then enhance the complex formation with DNA, which is the target in the chemotherapy of tumor. 5) Our group have succeeded in synthesizing series of palladium(II) ternary complexes having cis-planar four coordination geometry with N and O atoms and determining their structures, in which the aromatic heterocyclic ligands, bpy and phen has been structurally clarified as bidentate N, NЈ ligands and CBDCA, catechol or 2,3-naphthalenediol as the dianionic bidentate O, OЈ ligands.…”

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confidence: 99%

X-Ray Structure Characterization of Palladium(II) Ternary Complexes of Pyridinedicarboxylic and Phthalic Acid with Phenanthroline and Bipyridine

Wang

2005

“…Especially, one Pd(II) complex [Pd(bpy)(CBDCA)] (bpyϭ2,2Ј-bipyridine, CBDCAϭ1,1-cyclobutanedicarboxylate) is demonstrated to have better cytotoxic activity than cisplatin against P388 lymphocytic leukaemia cells. 1) Work in our laboratory has focused on studies of the synthesis and coordination chemistry of the Pd(II) complexes with various biologically relevant ligands and heterocyclic ligands. We have studied a series of bischelate square-planar complexes of the type [Pd(N-N)(O-NЈ)] or [Pd(N-N)(O-O)], where N-N is 1,10-phenranthroline (phen), 2,2Ј-bipyridine (bipy) or 2,2Ј-bipyridineamine (bpa), and O-NЈ or O-OЈ is the second bidentated ligand.…”

mentioning

confidence: 99%

Crystal Structures of Palladium(II) Ternary Complexes of 5-X-2-Aminobenzoic Acid with 1,10-Phenanthroline and Their Interaction with Calf Thymus DNA (Where X=Cl, Br and I)

Wang

Odoko

2005