8-Benzyl-6-hydroxy-8-azabicycl

Biotinylation of a Propargylated Cyclic (3′‐5′) Diguanylic Acid and of Its Mono‐6‐Thioated Analog Under “Click” Conditions

and triethylamine, followed by 5??dedimethoxytritylation, affords the 6?(2?cyanoethylthio)guanosine derivative in a yield of 70%. The 5??hydroxy function of this derivative is reacted with commercial N 2 ?isobutyryl?5??O ?(4,4??dimethoxytrityl)?2??O ?tert