It is an ester of pyrophosphoric acid with the nucleoside cytidine.

CDP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase cytosine.

In Bacillus subtilis and Staphylococcus aureus, CDP-activated glycerol and ribitol are necessary to build wall teichoic acid.

[1] In Rhodothermus marinus, CDP-activated inositol is necessary to form the phospholipid dialkylether glycerophosphoinositide, which contains inositol phosphate and ether-linked alkyl chains.

[2] CDP is commonly formed in the reaction dolichol + cytidine triphosphate (CTP) ⟶ dolichol-phosphate + CDP, which is prevalent in many biochemical pathways.