A compound of Formula I ##STR71## wherein: R1 is chosen from {HEAD ~ the group} consisting of alkyl, n cycloalkyl, n NHC alkyl, and {TAIL ~ arylalkyl}, wherein n=1 3, 
consisting of
A compound of Formula I # # STR71 # # wherein : R1 is chosen from { HEAD ~ the group } consisting of alkyl , n cycloalkyl , n NHC alkyl , and { TAIL ~ arylalkyl } , wherein n=1 3 ,
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH