{HEAD ~ A} is halogen, {TAIL ~ phenyl}, Sm phenyl, or NR5R6 
is
{ HEAD ~ A } is halogen , { TAIL ~ phenyl } , Sm phenyl , or NR5R6
HEAD HEAD HEAD HEAD HEAD REL OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH