Condensation of bis(2-chloroethyl)phosphoramidic dichloride (I) with the sodium salt of 3-buten-1-ol (II) gave the O-butenyl phosphoramidate (III), which was subsequently reacted with methylamine to produce the phosphorodiamidate (IV). Ozonization of the double bond of (IV), followed by oxidative workup with H2O2 yielded aldehyde (V). This was finally condensed with 2-mercaptoethanesulfonic acid cyclohexylamine salt (VI) to furnish the title compound.