The dendritic structures comprise linkers and {HEAD ~ branch groups} covalently bonded to each other in {TAIL ~ any} of various structural combinations 
The dendritic structures comprise linkers and { HEAD ~ branch groups } covalently bonded to each other in { TAIL ~ any } of various structural combinations
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH