Quantum chemical study of relative stability, electric field gradients at nitrogen atoms, rotational constants and electric dipole moments of all uracil, thymine and cytosine isomers

Ha, Tae–Kyu; Gunthard, H.H.

doi:10.1016/0022-2860(93)87051-a

Cited by 24 publications

(12 citation statements)

References 19 publications

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“…The information given in Table also holds for cytosine, isocytosine, and adenine, where applicable. Specific results for the latter three bases were reported earlier. − The increments for xanthine as listed in Table also hold for uracil and thymine, where applicable. For the latter nucleic acid bases, the results reported in previous work should be consulted. − …”

Section: Resultsmentioning

confidence: 85%

“…(ii) Wherever possible, zeroth order estimates for specific interactions were determined from suitably chosen model compounds. Choice of the model compounds and their quantum chemical data were described in earlier papers; − see also the Appendix.…”

Section: Notation Increment Model Computational Details and Data Anal...mentioning

confidence: 99%

“…A number of examples have been reported earlier. , As a further application, we may consider the following conversions (HF/6-31G(d,p) results, kcal/mol) which involve geometric isomer conversion of a hydroxyl substituent attached to an imidazole system. None of the structural fragments so far considered relevant in this work apply in a straightforward manner.…”

Section: Conclusion and Final Remarksmentioning

confidence: 99%

“…In previous papers, a system of energy increments based on quantum chemistry has been reported, from which the apparently erratic energies of conversion of geometric isomers of the pyrimidine nucleic acid bases cytosine, − uracil, − thymine, , and isocytosine and of the simplest purine nucleic acid base adenine may be reproduced fairly reliably. The increments may be perceived directly from the structural formula, either as repulsive or attractive interactions.…”

Section: Introductionmentioning

confidence: 99%

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Energy Increment Method Based on Quantum Chemical Results: A General Recipe for Approximative Prediction of Isomerization and Tautomerization Energies of Pyrimidine and Purine Nucleic Acid Bases and Related Compounds

Keller

Gunde

et al. 1999

J. Phys. Chem. A

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On the basis of HF/6-31G(d,p) and MP2/6-31G(d,p) quantum chemical computations of fully optimized structures of all isomers of cytosine, isocytosine, uracil, thymine, adenine, guanine, xanthine, and many model compounds, a system of additive energy increments has been derived, from which energies of conversion of geometric isomers (conformers) and tautomers of these nucleic acid bases may be reconstructed within approximately 0.5 kcal/mol. The increments are associated with specific structural fragments perceptible in the conventional structural formula. Physically, they correspond to repulsions between H atoms of -OH, -NH 2 , and dNH substituents and H atoms bound to C or N ring atoms and to attractions between H atoms of such substituents and sp 2 lone electron pairs localized at N atoms of the ring systems or of imino substituents. Tautomerization energies associated with displacements of H atoms among ring N atoms were included in the estimation process of the increments. Keto-enol and amino-imino tautomerization energies may be estimated from total electronic energies and increments of conformer conversion energies. The estimates also approximately apply for ∆U°(0) and ∆U°(T 0 ) (free molecules). The extended data set allowed some global structural features of the nucleic acid bases (such as formally aromatic 6-rings), which influence certain increments specifically, to be discerned. The set of increments presented may serve as a basis of a rather general recipe for predictive estimation of conformer and tautomer conversion energies of a wide range of hydroxy-and amino-substituted aromatic nitrogen bases and of effects of geometric isomerism on energetics of intermolecular H bonding involving -OH, -NH 2 , and dNH substituents and protonated keto groups.

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Section: Resultsmentioning

confidence: 85%

Section: Notation Increment Model Computational Details and Data Anal...mentioning

confidence: 99%

Section: Conclusion and Final Remarksmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Energy Increment Method Based on Quantum Chemical Results: A General Recipe for Approximative Prediction of Isomerization and Tautomerization Energies of Pyrimidine and Purine Nucleic Acid Bases and Related Compounds

Keller

Gunde

et al. 1999

J. Phys. Chem. A

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“…Detailed information on the gas‐phase tautomeric equilibria of DNA and RNA bases can be found in a series of previous experimental and theoretical papers 27–37. From all these studies it is possible to conclude that the various non‐canonical tautomeric forms of uracil, thymine and adenine lie so far apart in energy from the oxo tautomer that their spontaneous interconversion even at high temperature is unlikely.…”

Section: Resultsmentioning

confidence: 99%

Gas‐phase theoretical prediction of the metal affinity of copper(I) ion for DNA and RNA bases

2003

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The most stable tautomeric forms of free DNA and RNA bases were considered as substrates for the interaction of Cu(+) ion. Several suitable attachment sites were selected that involved mono- and bi-coordination of the cation. B3LYP/6-311 + G(2df,2p) bond energies showed that copper ion has the major affinity for guanine and cytosine bases. The proposed values of Cu(+) ion affinity are 59.9, 60.0, 80.2, 88.0 and 69.0 kcal mol(-1) for uracil, thymine, cytosine, guanine and adenine, respectively. The preference for the mono- or bi-coordination depends on the particular tautomer for each base.

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ChemInform Abstract: Quantum Chemical Study of Relative Stability, Electric Field Gradients at Nitrogen Atoms, Rotational Constants and Electric Dipole Moments of All Uracil, Thymine and Cytosine Isomers.

Gunthard

1994

ChemInform

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Quantum chemical study of relative stability, electric field gradients at nitrogen atoms, rotational constants and electric dipole moments of all uracil, thymine and cytosine isomers

Cited by 24 publications

References 19 publications

Energy Increment Method Based on Quantum Chemical Results: A General Recipe for Approximative Prediction of Isomerization and Tautomerization Energies of Pyrimidine and Purine Nucleic Acid Bases and Related Compounds

Energy Increment Method Based on Quantum Chemical Results: A General Recipe for Approximative Prediction of Isomerization and Tautomerization Energies of Pyrimidine and Purine Nucleic Acid Bases and Related Compounds

Gas‐phase theoretical prediction of the metal affinity of copper(I) ion for DNA and RNA bases

ChemInform Abstract: Quantum Chemical Study of Relative Stability, Electric Field Gradients at Nitrogen Atoms, Rotational Constants and Electric Dipole Moments of All Uracil, Thymine and Cytosine Isomers.

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