Ar is an optionally mono or di substituted group selected from {TAIL ~ ##STR41}## in which {HEAD ~ the optional substituents} are selected from the group consisting of alkyl of 1 6 carbon atoms, aralkyl of 7 10 carbon atoms, alkoxy of 1 6 carbon atoms, cyano, halo, nitro, carbalkoxy of 2 7 carbon atoms, or perfluoroalkyl of 1 6 carbon atoms 
Ar is an optionally mono or di substituted group selected from { TAIL ~ # # STR41 } # # in which { HEAD ~ the optional substituents } are selected from the group consisting of alkyl of 1 6 carbon atoms , aralkyl of 7 10 carbon atoms , alkoxy of 1 6 carbon atoms , cyano , halo , nitro , carbalkoxy of 2 7 carbon atoms , or perfluoroalkyl of 1 6 carbon atoms
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH REL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH