Building Blocks; Cross-linkers;
A PEG derivative, which contains a free amine that can be conjugated to biological molecules directly by an amide linkage (or via the corresponding isothiocyanate) and an azide that can be reduced to an amine for conjugation to other molecules. PEG derivatives are water soluble. Bifunctional water soluble compounds with flexible dimensions allow for conjugation of small molecules to proteins or molecular probes. 1-amino-11-azido-3,6,9-trioxaundecane can be reacted with small organic molecules for the synthesis of heterobifunctional compounds. It has been used to synthesize a mannose-fluorescein conjugate for the study of cell-surface mannose-specific lectins.