Synthesis and photochemical reactivity of phthalimidoadamantane–tyrosine conjugates
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Dipeptide 3, tetrapeptide 4 and pentapeptide 5, containing adamantylphthalimide and tyrosine, were synthesized and their photochemical reactivity investigated. Upon excitation to the triplet excited state, 3 does not give any photoproduct, although the photoinduced electron transfer (PET) should take place based on the thermodynamic properties. Tetrapeptide 4 and pentapeptide 5 are photochemically reactive, undergoing decomposition upon excitation. The lack of anticipated photodecarboxylation reactivity is explained by PET between the tyrosine and the phthalimide. However, deprotonation of the phenoxyl radical-cation giving phenoxyl radicals or back electron transfer giving starting material are probably faster than intrastrand single electron transfer which would lead to carboxyl radical and decarboxylation. The results indicate the importance of fine-tuning the molecular structure to attain the desired photoreactivity by the right choice of the reactants redox potential, as well as their acid/base properties.
KeywordsPhthalimide Tyrosine Peptides Photodecarboxylation Photoinduced electron transfer
These materials are based on work financed by the Croatian Science Foundation (HrZZ grant no. IP-2014-09-6312). The authors declare that they have no conflict of interest.
- 1.M. Horvat, K. Mlinarić-Majerski, N. Basarić, Croatica Chem. Acta 83, 179 (2010)Google Scholar
- 3.A.G. Griesbeck, W. Kramer, M. Oelgemöller, Synlett 1169 (1999)Google Scholar
- 8.A.G. Griesbeck, M. Oelgemöller, Synlett 492 (1999)Google Scholar
- 9.U.C. Yoon, P.S. Mariano, Chapter 85, in Handbook of Organic Photochemistry and Photobiology, 2nd edn., ed. by W.M. Horspool, F. Lenci (CRC Press, Boca Raton, 2004), pp. 1–15Google Scholar
- 10.U.C. Yoon, P.S. Mariano, in Organic Photochemistry and Photophysics, ed.by V. Ramamurthy, K. Schanze (CRC Press, Taylor & Francis Group, Boca Raton, 2006), pp. 179–206Google Scholar
- 14.A.G. Griesbeck, M. Oelgemöller, J. Lex, A. Haeusler, M. Schmittel, Eur. J. Org. Chem. 1831 (2001)Google Scholar
- 30.N. Cindro, I. Halasz, K. Mlinarić-Majerski, N. Basarić, Eur. J. Org. Chem. 929 (2013)Google Scholar
- 31.L. Mandić, K. Mlinarić-Majerski, A.G. Griesbeck, N. Basarić, Eur. J. Org. Chem. 4404 (2016)Google Scholar
- 38.V. Dourtoglou, B. Gross, V. Lambropoulou, C. Zioudrou, Synthesis 572 (1984)Google Scholar
- 41.Handbook of Photochemistry, ed. by M. Montalti, A. Credi, L. Prodi, M.T.Gandolfi (CRC Taylor and Francis, Boca Raton, 2006)Google Scholar
- 43.T. Montenay-Garestier, in Excited states of biological molecules, ed.by J.B. Birks (Wiley, London, 1976) pp. 207–216Google Scholar