Book of Abstracts - Ruhr-Universität Bochum

P-34
ISBOMC `10 5.7 – 9.7. 2010 Ruhr-Universität Bochum
Photocytotoxicity and DNA Cleavage Activity of 2-Ferrocenyl Adducts having
Imidazophenanthroline and Imidazophenanthrene Moieties
Basudev Maity, a Mithun Roy, a Sounik Saha, a Ritankar Majumdar, b Rajan R. Dighe, b and Akhil R.
Chakravarty* a
a Indian Institute of Science, Department of Inorganic and Physical Chemistry, b Department of
Molecular Reproduction, Development and Genetics, Sir C V Raman avenue, 560012, Bangalore,
India. E-mail: basudev@ipc.iisc.ernet.in
Ferrocene is an important constituent in the field of bioorganometallic chemistry related to nucleic
acids in spite of having any effective anticancer activity. 1 It is the ferrocenium cation, the oxidized
form of ferrocene, which is responsible for the anticancer activity. 2 The designing of new ferrocenebased
molecules showing photo-induced DNA cleavage and/or photocytotoxic activities are of
interests for their potential applications in the field of molecular biology, biotechnology and
particularly in medicine. This presentation includes the synthesis, characterization, interactions with
DNA, photo-induced DNA cleavage activity and photocytotoxicity of 2-ferrocenylimidazophenanthroline
(1) 3 and 2-ferrocenyl-imidazophenanthrene (2). To understand the role of the
ferrocenyl moiety, 2-phenyl-imidazophenanthroline (3) 4 has been studied as a control species.
Compound 2 has been characterized by X-ray crystallography. The interaction of the compounds with
DNA has been studied by UV-visible absorption titration and thermal denaturation methods. All the
compounds show good binding affinity to calf thymus DNA with intrinsic binding constant values of
~10 5 M -1 . The thermal denaturation data suggest DNA groove binding nature of the compounds. They
show poor chemical nuclease activity in the presence of H2O2 as an oxidizing agent and are inactive in
the presence of cellular reducing agent glutathione. Compound 1 shows significant photo-induced
DNA cleavage activity in UV-A light of 365 nm and visible light of 488 (blue light) and 530 nm
(green light). The mechanistic investigations of the DNA cleavage activity reveal the involvement of
reactive oxygen species. The photocytotoxicity of the compounds in human cervical HeLa cancer cell
line has been studied in UV-A light of 365 nm.
References
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2. G. Tabbì, C. Cassino, G. Cavigiolio, D. Colangelo, A. Ghiglia, I.Viano, D. Osella, J. Med. Chem.
2002, 45, 5786-5796.
3. F. Zapata, A. Caballero, A. Espinosa, A. Tárraga, P. Molina, J. Org. Chem. 2008, 73, 4034–4044.
4. N. M. Shavaleev, H. Adams, J. A. Weinstein, Inorg. Chim. Acta 2007, 360, 700–704.
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