{TAIL ~ R7} is OH, lower alkyl, {HEAD ~ phenyl}, benzyl, R3 phenyl or R3 benzyl 
{ TAIL ~ R7 } is OH , lower alkyl , { HEAD ~ phenyl } , benzyl , R3 phenyl or R3 benzyl
TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH