Development of a novel selective detection method for 5-formyl-2′-deoxyuridine by fluorescent derivatization

5-Formyl-2'-deoxyuridine (fdUrd) is derived from the oxidation of thymidine and is known to induce mutation (A:T to G:C) in DNA. We planned to develop a novel selective detection method for fdUrd in oligodeoxynucleotide (ODN) based on specific fluorescent derivatization of fdUrd using 2-aminothiophenol derivatives (ATs) as fluorogenic reagents. To achieve this goal, we first synthesized 5-(benzothiazol-2-yl)-2'-deoxyuridine derivatives (btdUrds) via the reaction between fdUrd and 5-substituted ATs. We report herein the synthesis and UV absorbance and fluorescence properties of btdUrds in different pH conditions.