R4 is halogen, alkoxy, {HEAD ~ phenylthio} or {TAIL ~ phenoxy}, which may be substituted or unsubstituted 
R4 is halogen , alkoxy , { HEAD ~ phenylthio } or { TAIL ~ phenoxy } , which may be substituted or unsubstituted
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH