Combinatorial multinuclear NMR and X-ray diffraction studies of uranium(VI)-nucleotide complexes
2005 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 127, no 43, 15236-15247 p.Article in journal (Refereed) Published
The complex formation of uranium(VI) with four nucleoticles, adenosine- (AMP), guanosine(GMP), uridine- (UMP), and cyticline-monophosphate (CMP), has been studied in the alkaline pH range (8.5-12) by H-1, P-31, C-13, and O-17 NMR spectroscopy, providing spectral integral, chemical shift, homo and heteronuclear coupling, and diffusion coefficient data. We find that two and only two complexes are formed with all ligands in the investigated pH region independently of the total uranium(VI) and ligand concentrations. Although the coordination of the 5'-phosphate group and the 2'- and 3'-hydroxyl groups of the sugar unit to the uranyl ions is similar to that proposed earlier (Feldman complex), the number and the structures of the complexes are different. The uranium-to-nucleotide ratio is 6:4 in one of the complexes and 3:3 in the other one, as unambiguously determined by a combinatorial approach using a systematic variation of the ratio of two ligands in ternary uranium(VI)-nucleotide systems. The structure of the 3:3 complex has been determined by single-crystal diffraction as well, and the results confirm the structure proposed by NMR in aqueous solution. The results have important implications on the synthesis of oligonucleotides.
Place, publisher, year, edition, pages
2005. Vol. 127, no 43, 15236-15247 p.
ligand-exchange dynamics, adenine-nucleotides, metal-ions, adenosine 5'-triphosphate, aqueous-solution, uranyl ions, photocleavage, coordination, chelation, binding
IdentifiersURN: urn:nbn:se:kth:diva-15152DOI: 10.1021/ja0550273ISI: 000232933900071ScopusID: 2-s2.0-27544493683OAI: oai:DiVA.org:kth-15152DiVA: diva2:333193
QC 201005252010-08-052010-08-05Bibliographically approved