Fosaprepitant-d4 Dimeglumine is a deuterated compound of Fosaprepitant Dimeglumine. Fosaprepitant Dimeglumine has a CAS number of 265121-04-8. Fosaprepitant Dimeglumine is the dimeglumine salt form of fosaprepitant, the water-soluble, N-phosphorylated prodrug of aprepitant, with antiemetic activity. Upon intravenous administration and rapid conversion to aprepitant, this agent binds selectively to the human substance P/neurokinin 1 (NK1) receptors in the central nervous system (CNS). This inhibits receptor binding of the endogenous substance P and prevents substance P-induced emesis.