Сhemo- and regioselective modification of adenosine with tertiary cyanopropargylic alcohols

Adenosine reacts with tertiary cyanopropargylic alcohols under mild conditions (K2CO3, DMF, 20-25 °C, 4-30 h) with 100% chemo- and regioselectivity by the way of two vicinal hydroxy groups of the ribose moiety to afford (in 52-72% yield) a novel family of adenosine cyclic ketals possessing cyano and hydroxyalkyl functions.