17039-17-7Relevant articles and documents
The role of phosphate in the action of thymidine phosphorylase inhibitors: Implications for the catalytic mechanism
Jain, Harsh V.,Rasheed, Roshni,Kalman, Thomas I.
, p. 1648 - 1651 (2010)
The design and synthesis of 5-fluoro-6-[(2-aminoimidazol-1-yl)methyl]uracil (AIFU), a potent inhibitor of thymidine phosphorylase (TP) with Ki-values of 11 nM (ecTP) and 17 nM (hTP), are described. Kinetic studies established that the type of inhibition of TP by AIFU is uncompetitive with respect to inorganic phosphate (or arsenate). The results obtained suggest that AIFU and other zwitterionic thymine analog inhibitors of TP act as transition state analogs, mimicking the anionic thymine leaving group, consistent with an SN2-type catalytic mechanism, and anchored by their protonated side chains to the enzyme-bound phosphate by electrostatic and H-bonding interactions.
The Peculiar Case of the Hyper-thermostable Pyrimidine Nucleoside Phosphorylase from Thermus thermophilus**
Kaspar, Felix,Neubauer, Peter,Kurreck, Anke
, p. 1385 - 1390 (2021/01/29)
The poor solubility of many nucleosides and nucleobases in aqueous solution demands harsh reaction conditions (base, heat, cosolvent) in nucleoside phosphorylase-catalyzed processes to facilitate substrate loading beyond the low millimolar range. This, in turn, requires enzymes that can withstand these conditions. Herein, we report that the pyrimidine nucleoside phosphorylase from Thermus thermophilus is active over an exceptionally broad pH (4–10), temperature (up to 100 °C) and cosolvent space (up to 80 % (v/v) nonaqueous medium), and displays tremendous stability under harsh reaction conditions with predicted total turnover numbers of more than 106 for various pyrimidine nucleosides. However, its use as a biocatalyst for preparative applications is critically limited due to its inhibition by nucleobases at low concentrations, which is unprecedented among nonspecific pyrimidine nucleoside phosphorylases.
PHOSPHORAMIDATE DERIVATIVES OF 5 - FLUORO - 2 ' - DEOXYURIDINE FOR USE IN THE TREATMENT OF CANCER
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Page/Page column 66-67, (2012/09/21)
Phosphoramidate derivatives of 5-fluoro-2'-deoxyuridine are disclosed for use in the treatment of cancer, especially in the treatment of cancer where the patient shows resistance, for example, in a patient with cells with a lowered level of nucleoside transporter proteins and/or with nucleoside kinase-deficient cells and/or with mycoplasma-infected cells and/or with cells with a raised level of thymidylate synthase.