Merck, D4022-50MG, P¹,P⁵-Di(adenosine-5′) pentaphosphate pentasodium salt

P¹,P⁵-Di(adenosine-5′) pentaphosphate (Ap5A) is a diadenosine polyphosphate, which has a tail-to-tail dimer structure. Ap5A is synthesized in a twostep process involving the formation of adenosine 5′-tetraphosphate (P4A) from the ATP and trimeta-phosphate (P3). In the second step, P4A is converted to Ap5A. The synthesis of Ap5A requires a pH optimum in the range of 7.5 to 8.5 and is modulated by metal ions.