Para aminoacetanilide and {HEAD ~ para nitroacetanilide} can also be used in {TAIL ~ the presence} of sodium ferrocyanide 
Para aminoacetanilide and { HEAD ~ para nitroacetanilide } can also be used in { TAIL ~ the presence } of sodium ferrocyanide
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH