The Facile and Efficient Synthesis of 8-Chloroadenosine $3^I,5^I$-cyclic monophosphate by phosphorylative cyclization of 8-chloroadenosine and its characterization by$^1 H and 13^C$ NMR spectroscopy

Purine nucleosides were chlorinated by the reaction of acyl chloride in DMF with MCPBA under mild conditions with moderate yields. And, satisfactory method for the synthesis of ribonucleoside-$3^{I},5^{I}$-cyclic phosphates and its characterization by$^{1}H$ and $^{13}C$ nmr spectroscopy is described.