The molecule is a cyclic purine dinucleotide that is the 3',5'-cyclic dimer of MP. It has a role as an immunomodulator and a signalling molecule. It is a guanyl ribonucleotide and a cyclic purine dinucleotide. It is a conjugate acid of a c-di-GMP(2-).
2-amino-9-[(1S,6R,8R,9R,10S,15R,17R,18R)-17-(2-amino-6-oxo-1H-purin-9-yl)-3,9,12,18-tetrahydroxy-3,12-dioxo-2,4,7,11,13,16-hexaoxa-3lambda5,12lambda5-diphosphatricyclo[13.3.0.06,10]octadecan-8-yl]-1H-purin-6-one