The molecule is a cyclic pyrimidine dinucleotide that consists of two UMP units cyclised via 3',5'-linkages, major species at pH 7.3. It is an organophosphate oxoanion and a cyclic pyrimidine dinucleotide.
1-[(1S,6R,8R,9R,10S,15R,17R,18R)-17-(2,4-dioxopyrimidin-1-yl)-9,18-dihydroxy-3,12-dioxido-3,12-dioxo-2,4,7,11,13,16-hexaoxa-3lambda5,12lambda5-diphosphatricyclo[13.3.0.06,10]octadecan-8-yl]pyrimidine-2,4-dione