Syntheses and fluorescence of RNA conjugates having pyrene-modified adenosine and nitrobenzene-modified uridine base pairs

We prepared RNA duplexes possessing 2′-O-(1-pyrenylmethyl)adenosine and 5-(4-nitrophenyl)uridine base pairs. In the duplexes, pyrene serves as a photo-excitable electron donor and 5-(4-nitrophenyl)uridine acts as an electron acceptor. The donor-acceptor-modified RNA duplexes showed very weak fluorescence originating from the pyrene monomer and excimer emissions, which occur due to electron transfer from the excited pyrene to the nitrobenzene acceptor.

RNA duplexes possessing 2′-O-(1-pyrenylmethy)adenosine and 5-(4-nitrophenyl)uridine base pairs were prepared. The RNA duplexes showed very weak fluorescence due to pyrene monomer and excimer emissions, which resulted from the electron transfer from the excited pyrene to the nitrobenzene acceptor.