RESUMO
The crystal structures of [Pt(NH3)2CPrDCA].H2O (I), [Pt(CH3NH2)2CPrDCA] (II), and [Pt(dmbn) CPrDCA].2.5H2O (III) (where CPrDCA is 1,1-cyclopropanedicarboxylate; dmbn is 2,3-dimethyl-2,3-butyldiamine) are determined. Compound I crystallizes in the orthorhombic space group Pnma with the cell dimensions: a = 6.517(2), b = 9.709(3), c = 14.205(5) A, Z = 4, R = 0.058. Compound II is monoclinic with space group P2(1)/n, a = 9.648(3), b = 8.720(2), c = 12.770(4) A, beta = 107.12(2), Z = 4, R = 0.059. Compound III belongs to the monoclinic system space group P2(1)/m with the cell dimensions: a = 6.494(1), b = 19.638(3), c = 6.606(1)A, beta = 94.44(1), Z = 2, R = 0.038. Electronic structures of the complexes are studied and the correlation between structure of the amine ligands and biological activity of the complexes is explored.
Assuntos
Antineoplásicos/química , Ácidos Dicarboxílicos/química , Compostos Organoplatínicos/química , Conformação Molecular , Relação Estrutura-AtividadeRESUMO
The interaction of cis-[Pt(NH3)2Cl2] with nucleosides, as constituents of DNA, was studied by spectrophotometric, 13C NMR and CNDO/2 methods. The apparent stability constants of the complexes formed and the initial rate of formation were determined. The sites of binding of nucleoside (or nucleotide) with Cisplatin were ascertained and the electronic structure of the model coordination compounds of Cisplatin and guanine was calculated by MO approach. On the basis of the obtained results, the mechanism of the antitumour action of Cisplatin was discussed, and a new possible mode of bonding of Cisplatin with DNA was proposed.