R11 is independently selected from {HEAD ~ the group} consisting of {TAIL ~ alkyl} and aryl; and 
R11 is independently selected from { HEAD ~ the group } consisting of { TAIL ~ alkyl } and aryl ; and
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH