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QT-034
Comparing
computational and chemometric approaches to calculate aromatic bond lengths:
a case of nucleobases
Rudolf
Kiralj (PQ), Márcia Miguel Castro Ferreira (PQ)*. marcia@iqm.unicamp.br
Instituto
de Química, Universidade Estadual de Campinas, Campinas 13083-862,
SP, Brasil
Palavras
Chave: Pauling p-bond
order, HCA-PCA best model selection, dimer geometry optimization
Nucleobases
or nucleic acid bases are natural or synthetic carbohydrate derivatives
of heterocyclic and carbocyclic compounds. Their physical, chemical, biochemical,
pharmacologic and physiologic effects can be well reflected through, or
correlated with nucleobase bond lengths (CC, CN, CO). This work deals with
various chemometric (univariate, multivariate based mainly on Pauling p-bond
orders and bond electrotopological indices) and computational (ab initio,
semi-empirical, molecular mechanics) approaches to calculate these bond
lengths. The coupled HCA-PCA procedure on the results from all these calculations
reveals that multivariate chemometric methods are better than univariate
ones, and at the same level as semi-empirical and molecular mechanics methods.
The maximum power in reproducing experimental bond lengths comes from nucleobase
dimer geometry optimization at ab initio level.
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26a Reunião Anual da Sociedade Brasileira de Química - SBQ