{TAIL ~ A compound} 1, wherein said compound is selected from {HEAD ~ the group} consisting of: 
{ TAIL ~ A compound } 1 , wherein said compound is selected from { HEAD ~ the group } consisting of :
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH