| Popis: |
trans-[(CH2NH2)2Pt(9-EtGH)Cl]Cl (1) and trans-[(CH3NH2)2Pt(9-EtGH)2]Cl2 (2) with 9-EtGH=9-ethylguanine have been prepared and studied. Pt binding in both compounds is through N7, as evident from 195Pt-1H(8) coupling (1) and X-ray crystallography (2), respectively. The X-ray structure of 2 shows the cation to be centrosymmetric, with the two methylamine ligands disordered over two positions. In Me2SO-d6, the cation of 2 forms Watson-Crick hydrogen bonds with added 1-methylcytosine (1-MeC), as shown by concentration-dependent 1H NMR spectroscopy. The solution behaviour (water) of 1 is remarkable in that it undergoes a partial redistribution according to 2(1)→(2)+trans-(CH3NH2) 2Pt→Cl2 in addition to N7,N1-bridge formation. If realized with DNA, this reaction could facilitate a migration of a monofunctionally bound trans-diamineplatinum(II) entity along DNA or its removal from DNA. |
