Fluorescent 7- and 8-methyl etheno derivatives of adenosine and 6-amino-9-ethylpurine: syntheses and fluorescence properties.

Two fluorescent adenosine derivatives (5 and 7) (Sch. 1) and two 6-amino-9-ethylpurine derivatives (6 and 8) (Sch. 1), were synthesised using 2-chloropropanal and 3-chloropropyne as reagents. The structures of the products were determined by spectroscopic and spectrometric methods (1H-, 13C- and 2D NMR, MS, UV and fluorescence spectrometry). Their fluorescence properties were determined and found to be similar to those of ethenoadenosine. Also, the stabilites of 5 and 7 in aqueous solutions were determined and found to be higher than that of the etheno derivative of adenosine.