COMPLEX OF CIS-(NH3)2PTCL2 WITH GUANYLYL(3'-5')-CYTIDINE

The predominant complex formed by the reaction of cis-(NH3)2PtCl2 and guanylyl(3′-5′)cytidine has been isolated. The molar ratio of the binding of cis-(NH3)2PtCl2 to guanylyl(3′-5′)-cytidine is 1:2. The values of proton dissociation constant due to guanine and cytosine bases provide useful information for determining the binding site of the isolated complex. In addition, nmr and ir spectral data were used to determine the binding site. cis-(NH3)2PtCl2 coordinates to guanylyl(3′-5′)cytidine through N(7) position of the guanine base, but cytosine base does not participate in the binding to cis-(NH3)2Pt2+. Interbase crosslink has not been detected. The binding specificity of cis-(NH3)2PtCl2 to guanine base is discussed. © 1979.