Isn't it ATP? * Strictly speaking, a nucleotide has only the one phosphate group. When there are three phosphate groups, the compound is named along these lines: "(base + sugar) triphosphate". So, for example, ATP is named adenosine triphosphate. Likewise for the others: CTP = cytidine triphosphate
GTP = guanosine triphosphate TTP = thymidine triphosphate UTP = uridine triphosphate