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