Sample records for chlorouracils

  1. Structure, stability and function of 5-chlorouracil modified A:U and G:U base pairs

    Energy Technology Data Exchange (ETDEWEB)

    Patra, Amritraj [Vanderbilt Univ., Nashville, TN (United States); Harp, Joel [Vanderbilt Univ., Nashville, TN (United States); Pallan, Pradeep S. [Vanderbilt Univ., Nashville, TN (United States); Zhao, Linlin [Vanderbilt Univ., Nashville, TN (United States); Abramov, Mikhail [Rega Inst. for Medical Research (Belgium); Herdewijn, Piet [Rega Inst. for Medical Research (Belgium); Univ. of Evry-Val-d' Essonne (France); Egli, Martin [Vanderbilt Univ., Nashville, TN (United States)


    The thymine analog 5-chlorouridine, first reported in the 1950s as anti-tumor agent, is known as an effective mutagen, clastogen and toxicant as well as an effective inducer of sister-chromatid exchange. Recently, the first microorganism with a chemically different genome was reported; the selected Escherichia coli strain relies on the four building blocks 5-chloro-2'-deoxyuridine (ClU), A, C and G instead of the standard T, A, C, G alphabet [Marlière,P., Patrouix,J., Döring,V., Herdewijn,P., Tricot,S., Cruveiller,S., Bouzon,M. and Mutzel,R. (2011) Chemical evolution of a bacterium’s genome. Angew. Chem. Int. Ed., 50, 7109–7114]. The residual fraction of T in the DNA of adapted bacteria was <2% and the switch from T to ClU was accompanied by a massive number of mutations, including >1500 A to G or G to A transitions in a culture. The former is most likely due to wobble base pairing between ClU and G, which may be more common for ClU than T. To identify potential changes in the geometries of base pairs and duplexes as a result of replacement of T by ClU, we determined four crystal structures of a B-form DNA dodecamer duplex containing ClU:A or ClU:G base pairs. The structures reveal nearly identical geometries of these pairs compared with T:A or T:G, respectively, and no consequences for stability and cleavage by an endonuclease (EcoRI). The lack of significant changes in the geometry of ClU:A and ClU:G base pairs relative to the corresponding native pairs is consistent with the sustained unlimited self-reproduction of E. coli strains with virtually complete T→ClU genome substitution.

  2. A simple and sensitive fully validated HPLC-UV method for the determination of 5-fluorouracil and its metabolite 5.6-dihydrofluorouracil in plasma

    NARCIS (Netherlands)

    Maring, JG; Greijdanus, B; de Vries, EGE; Uges, DRA


    The authors developed a simple and sensitive, fully validated HPLC-UV method for the determination of both 5-FU and its metabolite DHFU in small-volume plasma samples. The analytes were separated on a 4.6 X 250 mm ID Atlantis dC18 5-mum column with isocratic elution at room temperature. Chlorouracil

  3. Vibrational study of a nucleoside analogue with antiviral activity, 5-chloro-2'-deoxyuridine, CDU. (United States)

    Bailey, L; Navarro, R; Hernanz, A


    The experimental FTIR and FT-Raman spectra of 5-chloro-2'-deoxyuridine have been assigned on the basis of normal coordinate analyses, in the light of observed and calculated wavenumbers and isotopic shifts. The results indicate that virtually all normal modes of IDU involve some degree of vibrational coupling between the chlorouracil base and the deoxyribose moiety.

  4. A robust synthesis of 7,8-didemethyl-8-hydroxy-5-deazariboflavin (United States)

    Bender, Matthias; Mouritsen, Henrik


    Summary The biosynthetic precursor of redox cofactor F420, 7,8-didemethyl-8-hydroxy-5-deazariboflavin, was prepared in four steps from 6-chlorouracil, 2-chloro-4-hydroxybenzaldehyde and bis-isopropylidene protected D-ribose. The latter aldehyde was transformed to the corresponding protected ribitylamine via the oxime, which was submitted to reduction with LiAlH4. Key advantage compared to previous syntheses is the utilization of a polyol-protective group which allowed the chromatographic purification of a key-intermediate product providing the target compound with high purity. PMID:27340481

  5. Inelastic processes of electron interactions with halouracils - cancer therapy agents (United States)

    Limbachiya, Chetan; Vinodkumar, Minaxi; Swadia, Mohit


    We report electron impact total inelastic cross sections for important cancer treatment agents, 5-fluorouracil (5FU), 5-chlorouracil (5ClU) and 5-bromouracil (5BrU) from ionization threshold through 5000 eV. We have employed Spherical Complex Optical Potential [1,2] method to compute total inelastic cross sections Qinel and Complex Scattering Potential - ionization contribution (CSP-ic) formalism, to calculate total ionization cross sections Qion. Electron driven ionization cross sections for these important compounds of therapeutic interest are reported for the first time in this work. In absence of any ionization study for these cancer therapy agents, we have compared the data with their parent molecule Uracil. Present cross sections may serve as a reference estimates for experimental work.

  6. A spectroscopic investigations of anticancer drugs binding to bovine serum albumin (United States)

    Bakkialakshmi, S.; Chandrakala, D.


    The binding of anticancer drugs (i) Uracil (U), (ii) 5-Fluorouracil (5FU) and (iii) 5-Chlorouracil (5ClU), to bovine serum albumin (BSA) at two levels of temperature was studied by the fluorescence of quenching method. UV/Vis, time-resolved fluorescence, Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR) and scanning electron microscope (SEM) analyses were also made. Binding constants (Ka) and binding sites (n) at various levels of temperature were calculated. The obtained binding sites were found to be equal to one for all the three quenchers (U, 5FU and 5ClU) at two different temperature levels. Thermodynamic parameters ΔH, ΔG and ΔS have been calculated and were presented in tables. Change in FTIR absorption intensity shows strong binding of anticancer drugs to BSA. Changes in chemical shifts of NMR and fluorescence lifetimes of the drugs indicate the presence of interaction and binding of BSA to anticancer drugs. 1H NMR spectra and SEM photographs also conform this binding.