Sp-Adenosine-5'-O- (1-thiotriphosphate) sodium

Sp-Adenosine-5'-O- (1-thiotriphosphate) (Sp-ATP-α-S), an isomer of the ATP-α-S sulfur-containing nucleotide derivative and a purinergic P2Y1 receptor agonist, effectively increases calcium mobilization in HEK293 cells harboring the P2Y1 receptor with an EC50 of 9.4 nM for the human receptor. It also inhibits ADP-induced human isolated platelet aggregation with a Ki value of 4 μM and prompts relaxation in carbamoylcholine-tightened guinea pig taenia coli, achieving an EC50 of 426 nM.