For example, {HEAD ~ naphthyl} may include {TAIL ~ its hydrogenated derivatives} such as tetrahydronaphthyl 
For example , { HEAD ~ naphthyl } may include { TAIL ~ its hydrogenated derivatives } such as tetrahydronaphthyl
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH