Prototropic molecular-zwitterion tautomerism of imidazole and pyrimidine
نویسندگان
چکیده
منابع مشابه
Experimental and theoretical study of enol-keto prototropic tautomerism and photophysics of azomethine-BODIPY dyads.
In this study we report about two novel azomethine–BODIPY dyads 1 and 2. The two dyads have been, respectively, synthesized by covalent tethering of tautomeric ortho-hydroxy aromatic azomethine moieties including N-salicylideneaniline (SA) and N-naphthlideneaniline (NA) to a BODIPY fluorophore. Both of the two dyads 1 and 2 show enol-imine (OH) structures dominating in the crystalline state. Dy...
متن کاملStudies on Prototropic Tautomerism in Neutral and Monoanionic Forms of Pyrimidines by Nuclear Magnetic Resonance Spectroscopy
NMR methods have been applied to evaluation of prototropic tautomerism, N (1)H ^ N (3) H. in several selected pyrimidines, viz. the neutral forms of isocytosine and 2-alkylthiopyrimidone-4, and the monoanionic forms of uracil, 5-fluorouracil and 4-thiouracil. The predominant tautomeric species of the neutral forms could be estimated only qualitatively from chemical shifts. For the monoanionic f...
متن کاملAb Initio Study of the Prototropic Tautomerism of Cytosine and Guanine and Their Contribution to Spontaneous Point Mutations
High-level quantum-chemical and quantum-dynamics calculations are reported on the tautomerization equilibria and rate constants of isolated and monohydrated cytosine and guanine molecules. The results are used to estimate the fraction of the bases present in the cell during DNA synthesis as the unwanted tautomers that forms irregular base pairs, thus giving rise to a spontaneous GC→AT point mut...
متن کاملDerivatives of the Triaminoguanidinium Ion, 2. Prototropic Tautomerism, Crystal and Molecular Structure of N,N,N-Tris(propan-2-iminyl)guanidine [1, 2]
Dedicated to Professor Gerhard Müller on the occasion of his 60th birthday The title compound, C10H20N6 (2), was prepared from N,N′,N′′-triaminoguanidinium chloride. Solventand temperature-dependent 1H NMR spectra indicating prototropic tautomerism were observed in solution. The crystal and molecular structure was determined by X-ray diffraction analysis. The compound crystallizes in the hexago...
متن کاملPyrazolo[3,4-d]pyrimidine ribonucleosides related to 2-aminoadenosine and isoguanosine: synthesis, deamination and tautomerism.
The syntheses and properties of 8-aza-7-deazapurine (pyrazolo[3,4-d]pyrimidine) ribonucleosides related to 2-aminoadenosine and isoguanosine are described. Glycosylation of 8-aza-7-deazapurine-2,6-diamine 5 with 1-O-acetyl-2,3,5-tri-O-benzoyl-beta-D-ribofuranose (12) in the presence of BF(3) x Et(2)O as a catalyst gave the N(8) isomer 14 (73%) with a trace amount of the N(9) isomer 13a (4.8%). ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biopolymers and Cell
سال: 1995
ISSN: 0233-7657,1993-6842
DOI: 10.7124/bc.000401