Synthesis of a Benzophenone C-Nucleoside as Potential Triplet Energy and Charge Donor in Nucleic Acids

Abstract

A synthetic route to the C-nucleoside that bears benzophenone as a DNA base substitution directly at the anomeric center of the 2′-deoxyribofuranoside was worked out. Furthermore, the α-anomer of this artificial nucleoside was converted synthetically into the corresponding DNA building block and incorporated into two representative oligonucleotides by automated phosphoramidite chemistry. The chromophore-modified DNA was characterized by methods of optical spectroscopy. The absorption band at ∼350 nm can be used for selective excitation of the benzophenone chromophore outside the nucleic acid absorption range, which makes the benzophenone nucleoside potentially useful for photochemical and photobiological applications.