Concise and efficient synthesis of 3'-O-tetraphosphates of 2'-deoxyadenosine and 2'-deoxycytidine

We describe concise and efficient synthesis of biologically very important 3'-O-tetraphosphates namely 2'-deoxyadenosine-3'-O-tetraphosphate (2'-d-3'-A4P) and 2'-deoxycytidine-3'-O-tetra-phosphate (2'-d-3'-C4P). N(6)-benzoyl-5'-O-levulinoyl-2'-deoxyadenosine was converted into N(6)-benzoyl-5'-O-levulinoyl-2'-deoxyadenosine-3'-O-tetraphosphate in 87% yield using a one-pot synthetic methodology. One-step concurrent deprotection of N(6)-benzoyl and 5'-O-levulinoyl groups using concentrated aqueous ammonia resulted 2'-d-3'-A4P in 74% yield. The same synthetic strategy was successfully employed to convert N(4)-benzoyl-5'-O-levulinoyl-2'-deoxycytidine into 2'-d-3'-C4P in 68% yield.