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Biomedical subjects

G W Nyce

Publications and source records attributed to G W Nyce.

2 recordsLinked to original sources

Synthesis of arene-soluble mixed-metal uranium/zirconium complexes using the dizirconium nonaisopropoxide ligand.

The utility of polydentate monoanionic [Zr(2)(O(i)Pr)(9)](-) (dzni) in generating arene-soluble, mixed-metal Zr/U complexes is described. K[Zr(2)(O(i)Pr)(9)] reacts readily with UI(3)(THF)(4) to form [Zr(2)(O(i)Pr)(9)]UI(2)(THF), 1, in >90% yield. The integrity of the [[Zr(2)(O(i)Pr)(9)]U](2+) unit in 1 was examined by the reaction of 1 with K(2)C(8)H(8), which formed the organometallic complex [Zr(2)(O(i)Pr)(9)]U(C(8)H(8)), 2. In contrast, the reaction of K[Zr(2)(O(i)Pr)(9)] with UCl(4) did not form U(IV)-dzni complexes, and only the ligand exchange product, [UCl(2)(O(i)Pr)(2)(DME)](2), 3, was isolated. The effect of the dzni ligand on the electrochemistry and near-infrared spectroscopy of U(III) is also described.

Journal Article↗

dTMP biosynthesis in Archaea.

The biosynthesis of dTMP has been studied in cell extracts of two different members of the domain Archaea, Methanosarcina thermophila and Sulfolobus solfataricus. In M. thermophila, the dTMP was formed from dUMP and [methylene-2H2]-5,10-methylenetetrahydrosarcinapterin generated in situ from added [methylene-2H2] formaldehyde and the tetrahydrosarcinapterin present in the cell extract. In S. solfataricus, the 5,10-methyl-enetetrahydro derivative of a synthetic fragment of sulfopterin, the modified folate present in these cells, served as the C1 donor. These data indicate that the Archaea thymidylate synthases carry out the same basic reaction which occurs in other organisms but use the 5,10-methylenetetrahydro derivatives of modified folates as C1 donors.

Deoxyuracil Nucleotides↗