“…Bispidine-type ligands can be easily modified to fulfill a task of attaching to the desired vector of biological object. Indeed, these molecules possess at least two sites that can be used for conjugation with biomolecules (see Figure , bottom right): (a) if X = OH and Y = H, then the hydroxyl could be modified to carbamate or propargyl ether moieties; if XY = O, then the carbonyl could be reduced to a hydroxyl moiety and all of the possibilities for hydroxyl functionalization are then applied; moreover, the bispidinic carbonyl group is known to form hydantoins. − (b) R groups could have linkable residues like SH, COOH, OH, and so on.…”