2'- O- (6- Aminohexylcarbamoyl)guanosine- 3', 5'- cyclic monophosphorothioate, Rp- isomer, immobilized on agarose gel (Rp-2'-AHC-cGMPS-Agarose)[2'- O- (6- Aminohexylcarbamoyl)guanosine- 3', 5'- cyclic monophosphorothioate, Rp- isomer, immobilized on agarose gel (Rp-2'-AHC-cGMPS-Agarose)]