7083-40-1Relevant articles and documents
Microwave-assisted Michael addition of some pyrimidine and purine nucleobases with α,β-unsaturated esters: A rapid entry into carboacyclic nucleoside synthesis
Khalafi-Nezhad,Zarea,Soltani Rad,Mokhtari,Parhami
, p. 419 - 424 (2005)
An efficient procedure for the synthesis of some carboacyclic nucleosides via microwave-assisted Michael addition of various nucleobases to α,β-unsaturated esters in the presence of tetrabutylammonium bromide (TBAB) and DABCO is described. Using this method, some pyrimidine and purine nucleobases have been alkylated regioselectively in moderate to high yields and short reaction time. Georg Thieme Verlag Stuttgart.
Spectroscopic Evaluation of Novel Adenine/Thymine-Conjugated Naphthalenediimides: Preference of Adenine-Adenine over Thymine-Thymine Intermolecular Hydrogen Bonding in Adenine- and Thymine-Functionalized Naphthalenediimides
Patra, Digambara,Al Homsi, Nadine,Jaafar, Sara,Neouchy, Zeina,Elaridi, Jomana,Koubeissi, Ali,Bouhadir, Kamal H.
, p. 307 - 318 (2019/01/11)
The synthesis and spectroscopic characterization of novel nucleobase (adenine/thymine)-conjugated naphthalenediimides (NDIs), namely, NDI-AA, NDI-TT, and NDI-AT have been successfully achieved. NDI-AA, NDI-TT and NDI-AT have similar absorption in the 300–400?nm region. The effect of solvent on the absorption spectrum indicates aggregation, either through intermolecular π-σ interaction among the main chromophore or through intermolecular hydrogen bonding between adenine and adenine group. Addition of water does not assist hydrogen bond formation between thymine-thymine, rather increasing the polarity of the solvent encourages π-σ interaction among NDI-TTs. No spectral change for NDI-TT with increasing temperature confirms hydrogen bonding is not playing a crucial role in NDI-TT. A fluorescence study on NDI-AA also establishes excimer formation along with ground state aggregation. As the water content in the solvent mixture increases, aggregation of NDI-AA is discouraged due to adenine-adenine hydrogen bonding in accordance with earlier results. At the same time, the NDI-TT emission spectrum does not shift to the blue region and the intensity of the peak around 535?nm increases at the expense of fluorescence in 411?nm. Thus, increasing water content in the solvent mixture facilitates aggregation through π-σ interaction in NDI-TT as thymine-thymine hydrogen bonding is less pronounced.
Acidity and complex formation studies of 3-(adenine-9-yl)-propionic and 3-(thymine-1-yl)-propionic acids in ethanol-water media
Hammud, Hassan H.,El Shazly, Shawky,Sonji, Ghassan,Sonji, Nada,Bouhadir, Kamal H.
, p. 33 - 40 (2015/02/19)
The ligands 3-(adenine-9-yl)propionic acid (AA) and 3-(thymine-1-yl)propionic acid (TA) were prepared by N9-alkylation of adenine and N1-alkylation of thymine with ethylacrylate in presence of a base catalyst, followed by acid hydrolysis of the formed ethyl esters to give the corresponding propionic acid derivatives. The products were characterized by spectral methods (FTIR, 1H NMR and 13C NMR), which confirm their structures. The dissociation constants of ligands, were potentiometrically determined in 0.3 M KCl at 20-50 °C temperature range. The work was extended to study complexation behavior of AA and TA with various biologically important divalent metal ions (Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Mn2+ and Pb2+) in 50% v/v water-ethanol medium at four different temperatures, keeping ionic strength constant (0.3 M KCl). The order of the stability constants of the formed complexes decreases in the sequence Cu2+ > Pb2+ > Zn2+ > Ni2+ > Co2+ > Mn2+ > Cd2+ for both ligands. The effect of temperature was also studied and the corresponding thermodynamic functions (ΔG, ΔH, ΔS) were derived and discussed. The formation of metal complexes has been found to be spontaneous, and the stability constants were dependant markedly on the basicity of the ligands.
