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