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