International audience; The Stimulator of Interferon Genes (STING) plays an important role in innate immunity by inducing type I interferons in response to sensing viral or bacterial cytosolic DNA. Cyclic dinucleotides (CDNs) are known to activate STING. Here, we describe the synthesis and biological evaluation of two new 3’,3’-CDN, in which the internucleotide linkages were replaced, respectively, by a 1,2,3-triazole moiety (as more stable isosteres of phosphate linkers) and an unsaturated carbon chain (as flexibility can led to crucial binding affinity and specificity). Thus, CuAAC and macrocyclization by RCM are the two key steps