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DFT and TDDFT investigation of the Schiff base formed by tacrine and saccharin

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Abstract

Schiff bases have many chemical and biological applications in medicine and pharmaceuticals due to the presence of an imine group (−C=N−). These bases are used in many different fields of technology, and in photochemistry because of their photochromic properties. Here, the structural and electronic properties of the Schiff base formed by tacrine and saccharin (TacSac) were explored using density functional theory with the B3LYP, M06-2X, M06L, and ωB97XD functionals in combination with the 6-311++G(d,p) basis set. The time-dependent formalism was used at the B3LYP/6-311++G(d,p) level to obtain electronic transitions. The calculations were repeated in an implicit solvent model mimicking water, using the polarizable continuum model in conjunction with a solvation model based on a density approach. The results indicate that TacSac cannot form spontaneously, but can be obtained in mild reactions. However, the resulting Schiff base displays different characteristics to its monomers. It also has the potential for use in photochemical intramolecular charge-transfer systems.

Intramolecular charge transfer between HOMO and LUMO of TacSac

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Acknowledgements

The use of TUBITAK-ULAKBIM TRUBA resources for some of the calculations is gratefully acknowledged.

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Authors and Affiliations

  1. Department of Chemistry, Faculty of Science, Ege University, 35100, Bornova, Izmir, Turkey

    Nursel Acar

  2. Department of Biochemistry, Faculty of Science, Ege University, 35100, Bornova, Izmir, Turkey

    Cenk Selçuki

  3. Department of Chemistry, Faculty of Arts and Science, Ondokuz Mayıs University, Samsun, Turkey

    Emine Coşkun

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  1. Nursel Acar
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Correspondence to Nursel Acar.

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Acar, N., Selçuki, C. & Coşkun, E. DFT and TDDFT investigation of the Schiff base formed by tacrine and saccharin. J Mol Model 23, 17 (2017). https://doi.org/10.1007/s00894-016-3195-6

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