Nucleoside complexes

Fiskin, A. M., and M. Beer. 1965. Determination of Base Sequence in Nucleic Acids with the Electron Microscope. IV. Nucleoside Complexes with Certain Metal Ions. Biochem. 4,1287. 

In the situation with 1,2-diols, such as depicted in Scheme 4.1b, where the oxygens of the V02 grouping are not incorporated into the core, the dimeric structure of the complex is highly favored in aqueous solution. For a nucleoside complex, the VO bond of the V02 moiety are 1.625 lengths and 1.626 A, whereas the individual VO bonds of the core are 2.036 A and 1.983 A in length [3], Dimeric structures,... 

The diminished numerical values of the stability constants of metal nucleoside complexes indicate to a certain extent that structural changes of the metal complex may have occurred. However, it has to be emphasized that structural conclusions derived from equilibrium constants have to be regarded with extreme caution (71). Thus, different molecular designs have been proposed (71, 32). One of them has more or less the same structure like the chelates with the free bases (Fig. 1), the other suggestion indicates only one coordination site at the base residue (Fig. 3). 

Nucleoside analogues as chemotherapeutic agents 86ACR230. Nucleosides, complexes with metal carbonyls 85UK479. 

A number of papers have examined the interaction between platinum complexes and nucleosides. Mono-nucleoside complexes K[Pt(nucleoside)Cl3] (nucleoside = guanosine, inosine, or xanthosine), which are 1 1 electrolytes, have been characterized by chemical analyses and n.m.r. spectroscopy. K2[(PtCl3)2(adenosine)] was also prepared. Various halogenoplatinum nucleoside complexes have been obtained from acidic, neutral, and basic solutions, and the bonding modes of the nucleoside examined using n.m.r. and i.r. spectroscopy.In neutral or weakly acid media adenosine and... 

This has restricted many of our studies of Pt(II) complexes to intermediate fields (e.g. 4 7 T). Pt(IV) complexes are less anisotropic and the effect is less marked It is probable that CSA relaxation is partly responsible for our failure to observe Pt signals directly from Pt bound to macromolecules. CSA relaxation of Pt can also lead to the disappearance of Pt satellites from C or spectra. These are normally used as indications of binding sites. Pt couplings appear in the spectra of coupled ligand nuclei as 1 4 1 multiplets only if relaxation times are the same in Pt(I 0) and Pt species. Indications that differences could exist were noted in NMR studies by Erickson et al ( ) on 1,2-diaminoethane complexes, and Lallemand et al ( ) for nucleoside complexes. We have recently shown ) for trans-Pt(ethene)(2-carboxy-pyridine)Cl2 that the broadening of satellites at high field arises from Pt relaxation via the CSA mechanism. The effect on the satellite linewidths is proportional... 

From Figure 3, it is clear that the B/B interbase conformational angle (as well as the B/PtN dihedral angle) decreases significantly on going from the bis(nucleobase) complex, through the bis(nucleoside) complex, to the bis(nucleotide) complex. 

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