Guanosine(1) as the starting material, reacted with acetic anhydride to obtain 2',3',5'-tri-O-acetyl-guanosine(2), which reacted with Ts Cl to obtain 2-amino-6-tosyl-9-(2',3',5'-tri-O-acetyl-β-D-ribofuranosyl)purine(3). Compound 3 was diazotized with isoamyl nitrite and then reacted with dialkyl disulfides to afford 2-ethylthio-6-tosyl-9-(2',3',5'-tri-O-acetyl-β-Dribofuranosyl)purine(4). Finally, compounds 5 were acquired by aminolysis and deprotection of 4. Ten new compounds were synthesized and all compou...