5-(hydroxymethyl)-1,2-dihydro-1,2,4-triazol-3-one Arepitan oxidation impurity N-O Aprepitant Impurity 13 Aprepitant related impurities Aprepitant iMpurity (2R)-2-[(1R)-1-[3,5-Bis(trifluoroMethyl)phenyl]ethoxy]-3-(4-fluorophenyl)-5,6-dihydro-2H-1,4-oxazine Aprepitant Impurity 27 Defluoro Aprepitant Aprepitant Impurity 42 Aprepitant Impurity 32 Aprepitant Impurity B HCl Aprepitant Impurity 11 HCl Aprepitant Impurity 2 Aprepitant Impurity 75 1-(2,4-bis(trifluoromethyl)phenyl)ethan-1-ol Aprepitant iMpurity43 Aprepitant Impurity 35 Aprepitant Impurity C