Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 78 (1995), S. 1106-1111 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 5-methyl(15N2)[O2,O4-17O2]uridine (= (15N2)[O2,O4-17O 2]ribosylthymine; 15) was synthesized and analyzed by 15N- and 17O-NMR spectroscopy. (15N2)Urea was condensed with 2,3-dibromo-2-methylpropanoyl chloride (3) and cyclized to form (15N2)thymine (5). After glycosidation, the 17O isotopes were introduced in two separate steps: hydrolytic ring opening of 2,5′-anhydro derivative 9 and hydrolysis of 3-nitro-1H-1,2,4-triazole derivative 12 with labelled water in the presence of a strong base. The 15N- and 17O-NMR spectra (Fig.) of 15 in phosphate-buffered water serve as references for heteronuclear NMR spectra of labelled RNA fragments.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 79 (1996), S. 244-254 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general synthetic approach for the synthesis of 15N- and 17O-doubly labelled pyrimidine nucleosides is described. The 15N isotopes in uridine and the 17O isotope in the urea-derived carbonyl group of uridine and cytidine originate from (15N2)[17O]urea (5) which was synthesized from 15NH4Cl, thiophosgene (1), and H2[17O]. The third 15N isotope of cytidine in 4-position stems from the substitution of the 1,2,4-triazole moiety of (15N2)[O2-17O]uridine derivative 8a/b with 15NH4OH. Hydrolysis of the same key intermediate 8a/b with Na[17O]H/H2[17O] introduced the second 17O isotope into the 4-position of uridine. The 15N- and 17O-NMR spectra of the target compounds 12 and 14 in phosphate-buffered H2O serve as references for heteronuclear NMR spectra of labelled RNA fragments.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...