The compound 1 wherein R1 and R2 are phenyl and R3, R4 and {HEAD ~ R5} are {TAIL ~ each} independently a lower alkyl 
are
The compound 1 wherein R1 and R2 are phenyl and R3 , R4 and { HEAD ~ R5 } are { TAIL ~ each } independently a lower alkyl
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH