Stacking interaction of nucleobases: NMR investigations

Sapper, Helmut; Lohmann, W.

doi:10.1007/bf00537615

Cited by 24 publications

(10 citation statements)

References 19 publications

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“…However, for characterizing the transition states and the reaction intermediates, the situation is somewhat complicated by the fact that various types of complexes [22] that show different levels of stability in various solvents can be born, as shown by recently published data for related structures. [23] According to theoretical calculations, hydrogenbonded structures of nucleic acid bases are most stable in chloroform, T-shaped structures are preferred in dimethyl sulfoxide, and stacked structures predominate in methanol.…”

Section: Resultsmentioning

confidence: 98%

NMR Quantification of Tautomeric Populations in Biogenic Purine Bases

Bartl¹,

Zacharová²,

Sečkářová³

et al. 2009

Eur J Org Chem

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Purine bases such as purine, adenine, hypoxanthine, and mercaptopurine are known to exist in several tautomeric forms. Characterization of their tautomeric equilibria is important not only for predicting the regioselectivity of their N‐alkylation reactions, but also for gaining knowledge of the patterns with which these compounds of significant biological activity form hydrogen bonds with their biological targets. The tautomeric equilibria of purine and some purine derivatives in methanol and N,N‐dimethylformamide solutions were investigated by low‐temperature 1H and 13C NMR spectroscopy. The N(7)H and N(9)H tautomeric forms were quantified by integrating the individual 1H NMR signals at low temperatures. The Gibbs free energy differences were calculated and the effects of substitution on the N(7)H/N(9)H ratio discussed. A previously published theoretically predicted mechanism of the tautomeric exchange is compared with our measurements in deuteriated solvents. The influence of concentration on the temperature of coalescence indicates that supramolecular clusters play a significant role in this proton transfer process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

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Section: Resultsmentioning

confidence: 98%

NMR Quantification of Tautomeric Populations in Biogenic Purine Bases

Bartl¹,

Zacharová²,

Sečkářová³

et al. 2009

Eur J Org Chem

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“…The solutions for the NMR and IR experiments were obtained by dissolving the appropriate amounts of trans-RSV in DMSO-d 6 …”

Section: Methodsmentioning

confidence: 99%

“…[5] Furthermore, it is noteworthy that the interactions are widely applicable to the molecular recognition of host-guest molecules. [6,7] Aromatic antitumour antibiotics, such as doxorubicin, daunomycin, mitoxantrone, and actinomycin are widely used in clinical practice as basic components of combinations of drugs designed for treatment of various types of human cancers. It has been shown that at millimolar concentrations in aqueous solution, there is a strong tendency for aromatic anticancer drugs to exhibit self-association forming dimers and higher-order aggregates, which are stabilized by stacking interactions of the aromatic chromophores.…”

Section: Introductionmentioning

confidence: 99%

Stacking interaction study of trans‐resveratrol (trans‐3,5,4′‐trihydroxystilbene) in solution by Nuclear Magnetic Resonance and Fourier Transform Infrared Spectroscopy

Bonechi

Martini

Magnani

et al. 2008

Magnetic Reson in Chemistry

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Interactions between aromatic rings or other unsaturated systems, including pi-stacking and face-to-edge complexes, are the origin of many phenomena in both organic and biological chemistry. It is well known that these interactions play an important role in the stabilization of the stereo-structure of DNA and the tertiary structure of many proteins.Trans-resveratrol (trans-3,5,4'-trihydroxystilbene, trans-RSV) is a phytoalexin found in Vitis sp. and in many other plants and food products and has received much attention because of its possible positive health benefits. In this work, the pi-stacking interaction of trans-RSV was studied by nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. In particular, the proton chemical shift dependence of the RSV concentration in the range 2 x 10(-2) - 1 x 10(-5) M and temperature were analysed. Moreover, the dynamics of the supramolecular aggregates were studied by nuclear spin relaxation data.

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“…In Eqn (10) 6 , represents the shift at infinite dilution (monomeric N) and 6, the shift of a molecule in an infinitely long stack, while K is the association constant as defined in Eqn (8). By ignoring species larger than dimers, a relationship analogous to Eqn (10) is obtained: 6, is replaced by cSD, the upfield shift in a dimer, and K is replaced by 2K, (i.e.…”

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confidence: 99%