A process 2, wherein {HEAD ~ R1}, R2 and R3 are hydrogen and {TAIL ~ R4} is a lower alkyl group 
A process 2 , wherein { HEAD ~ R1 } , R2 and R3 are hydrogen and { TAIL ~ R4 } is a lower alkyl group
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH