{TAIL ~ A diphenylamine} 1, wherein R6 and R7 are {HEAD ~ each hydrogen} 
{ TAIL ~ A diphenylamine } 1 , wherein R6 and R7 are { HEAD ~ each hydrogen }
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD