R3 is 1 3 groups independently selected from {HEAD ~ the group} consisting of lower alkyl, lower alkoxy, COOH, NO2, NR4 R5, OH or {TAIL ~ halogeno} 
R3 is 1 3 groups independently selected from { HEAD ~ the group } consisting of lower alkyl , lower alkoxy , COOH , NO2 , NR4 R5 , OH or { TAIL ~ halogeno }
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 OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL