monohydrate (CAS NO.: ), with its systematic name of Phosphorothioic acid, S-(2-((3-aminopropyl)amino)ethyl) ester, hydrate, could be produced through many synthetic methods.

Following is one of the reaction routes:

1-(3-Aminopropyl)aziridine (IV) is converted to N-(2-bromoethyl)-1,3-propanediamine dihydrobromide (V) by adding the reagent of HBr. Next, (V) is converted to the thiophosphate WR-2721 (VI) with trisodium thiophosphoroate.