Stabilized N.sup.2,2-O-dibutyrylguanosine-3,5-cyclic phosphate and salts thereof

A method for producing a stabilized dibutyrylguanosine cyclic phosphate compound selected from the group consisting of N.sup.2,2'-O-dibutyrylguanosine-3',5'-cyclic phosphate and salts thereof which has a moisture content of not more than 3 percent by weight, which method consists essentially of subjecting a dibutyrylguanosine cyclic phosphate compound selected from the group consisting of N.sup.2,2'-O-dibutyrylguanosine-3',5'-cyclic phosphate and salts thereof selected from the group consisting of alkali metal salts, alkaline earth metal salts and ammonium salts, having a moisture content of more than 3 percent by weight to desiccation for a time sufficient to reduce the moisture content to not more than 3 percent by weight.