{HEAD ~ The compound} 3, wheren {TAIL ~ each R1 moiety} is a 1,4 phenylene moiety 
wheren
{ HEAD ~ The compound } 3 , wheren { TAIL ~ each R1 moiety } is a 1,4 phenylene moiety
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH