Journal of Molecular Modeling

, 22:213 | Cite as

A comparison of scytonemin and its carbon analogue in terms of antioxidant properties through free radical mechanisms and conformational analysis: a DFT investigation

Original Paper


Scytonemin is a UV absorbing sheath pigment synthesized uniquely by cyanobacteria. Its biological features has attracted interest ecologically (in microbial mat systems), medically (for therapeutic activity) and astrobiologically (as a key biomarker). Recently, a carbon analogue of scytonemin, in which two nitrogen atoms are replaced by carbon atoms was synthesized to elucidate the origin of biological activity by comparison with scytonemin. In this work, their structural/conformational aspects and relative antioxidant capacity are compared making use of DFT calculations to provide insight about the similarities and differences between the two. The carbon analogue of scytonemin, isoelectronic with scytonemin, has the same structural skeleton and a similar potential energy surface but the hydrogens on the carbons that replace the nitrogens cause the phenolic rings to rotate out of the plane which is obseved for scytonemin. Thermochemically, the carbon analogue of scytonemin prefers the same radical scavenging mechanism scytonemin does, the HAT mechanism, and has a lower homolytic bond dissociation enthalpy for the OH group than that of scytonemin and other known antioxidants like ascorbic acid. The carbon analogue of scytonemin is suggested to be a novel synthetic antioxidant.


Scytonemin Carbon analogue of scytonemin Antioxidant activity Radical scavenging DFT calculations 



This work has been funded by Bogazici University Research Funds BAP no: 15BO5P4

Supplementary material

894_2016_3094_MOESM1_ESM.docx (15 kb)
ESM 1 (DOCX 15 kb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of ChemistryBogazici UniversityIstanbulTurkey

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