Toward novel DNA binding metal complexes: structure and basic kinetic data of [M(9MeG)2(CH3OH)(CO)3]+(M = 99Tc, Re)

Inorg Chem. 2003 May 5;42(9):2818-20. doi: 10.1021/ic030028m.

Abstract

To study the interaction of the fac-[M(CO)(3)](+) moiety (M = (99m)Tc, (188)Re) with DNA bases, we reacted [M(OH(2))(3)(CO)(3)](+) with 9-methylguanine (9-MeG), guanosine (G), and 2-deoxyguanosine (2dG). Two bases bind to the metal center via the N7 atoms. X-ray structure analysis of [(99)Tc(CH(3)OH)(9-MeG)(2)(CO)(3)](+) (4) (monoclinic, I2/a, a = 28.7533(14) A, b = 8.0631(4) A, c = 32.3600(15) A, beta = 91.543(6) degrees, V = 7499.6(6) A(3), Z = 8) and [Re(OH(2))(9-MeG)(2)(CO)(3)](+) (7) (monoclinic, P2(1)/n, a = 12.2873(11) A, b = 16.0707(13) A, c = 14.1809(16) A, beta = 103.361(12) degrees, V = 2724.4(5) A(3), Z = 4) reveals that the two bases are in a head-to-tail (HT) orientation. Kinetic studies show that the rates of substitution of the purine bases are comparable to that of one of the active forms of cisplatin. The bis-substituted complexes are generally less stable than the platinum adducts, and metalation of the bases is reversible.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Crystallography, X-Ray
  • DNA / chemistry*
  • Deoxyguanosine / chemistry*
  • Guanine / analogs & derivatives*
  • Guanine / chemistry*
  • Kinetics
  • Molecular Conformation
  • Nuclear Magnetic Resonance, Biomolecular
  • Organometallic Compounds / chemical synthesis*
  • Organometallic Compounds / chemistry
  • Organotechnetium Compounds / chemical synthesis*
  • Organotechnetium Compounds / chemistry
  • Purines
  • Radiopharmaceuticals / chemical synthesis*
  • Radiopharmaceuticals / chemistry
  • Rhenium / chemistry*
  • Technetium / chemistry

Substances

  • Organometallic Compounds
  • Organotechnetium Compounds
  • Purines
  • Radiopharmaceuticals
  • 9-methylguanine
  • Guanine
  • Rhenium
  • Technetium
  • DNA
  • Deoxyguanosine
  • purine