R14 and {HEAD ~ R15} are {TAIL ~ each}, independently, hydrogen, alkyl of 1 12 carbon atoms, n Ar, p NR16 R17, or p N+R16 R17 R18 Y  
are
R14 and { HEAD ~ R15 } are { TAIL ~ each } , independently , hydrogen , alkyl of 1 12 carbon atoms , n Ar , p NR16 R17 , or p N+R16 R17 R18 Y
OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL 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