Synthesis and Properties of 2′-Deoxyadenosine Mimics Bearing a Thieno[3,2-d]pyrimidine Ring

Abstract

AbstractA C-nucleoside with a stable C–C glycosidic bond can be used as a building block for chemically modified oligonucleotides (ONs). In this study, two adenosine-like C-nucleosides (dSA and dSO2A) bearing thieno[3,2-d]pyrimidine rings were designed and synthesized. These analogues were synthesized via the Heck reaction, and their properties as monomer nucleosides were investigated. Both the dSA and dSO2A monomers were not recognized by adenosine deaminase (ADA). In addition, they exhibited fluorescence emissions in the UV and visible regions of dSA and dSO2A, respectively. Subsequently, dSA was converted into a phosphoramidite compound and incorporated into the ONs. The synthesized dSA-modified ONs formed a stable duplex with DNA and RNA complements comparable to natural adenosine. Furthermore, the modified ONs exhibited fluorescence emission derived from dSA.