| abstract |
Provided herein are novel ortho-Phthalaldehyde (OPA) containing linkers (OPA-L) and the use of OPA-L for the preparation of Antibody-drug conjugate (ADC) via the formation of Phthalimidine through the reaction of primary amine on antibody (e.g., residue of Lysine) and ortho-Phthalaldehyde. The advantage of this OPA-L is high reactivity and can be applied in different types of antibodies to form stably-linked conjugates. The use of OPA-L for the preparation of ADC is advantageous for mild and wide condition of conjugation, for instance, low percentage of organic solvent required, wide range of pH and temperature can be used. |