The compounds of {HEAD ~ this invention} wherein {TAIL ~ R} is NCS can be attached to a biomolecule through an amine group on the latter 
wherein
The compounds of { HEAD ~ this invention } wherein { TAIL ~ R } is NCS can be attached to a biomolecule through an amine group on the latter
OTH OTH OTH HEAD 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