The compounds of this invention wherein {TAIL ~ R} is OH can be attached to a biomolecule indirectly through {HEAD ~ a phosphoramidite} ultimately forming a phosphate linkage 
The compounds of this invention wherein { TAIL ~ R } is OH can be attached to a biomolecule indirectly through { HEAD ~ a phosphoramidite } ultimately forming a phosphate linkage
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH