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