Abstract: The invention provides a new oligopeptide linker intermediate and a preparation method thereof. The preparation method of the oligopeptide intermediate is easily carried out under mild reaction conditions, and since almost no side reactions occur in the reaction, the method produces a high-purity product with fewer impurities and easy to be purified, achieving unexpected technical effects.

Abstract: Provided is an antibody-drug conjugate (ADC) using one or more cysteine or derivatives thereof as linkers to couple one or more drugs at the limited binding sites of an antibody, making it possible to produce an ADC product with high drug payload, or to choose a drug with less toxicity, thereby obtaining an ADC product with wide therapeutic window. In addition, since a plurality of drugs may be coupled to one binding site, the ADC products obtained by the method of the present disclosure have better uniformity in the case of same DAR value. Moreover, the amount of antibody required for production may be greatly reduced, thereby lowering the cost. Compared with the antibody-drug conjugates coupled only one drug, the antibody-drug conjugates produced by the method of the present disclosure have the same inhibition or killing effect on tumor cells while using fewer drugs for coupling to the same site.

Abstract: The invention provides a new oligopeptide linker intermediate and a preparation method thereof. The preparation method of the oligopeptide intermediate is easily carried out under mild reaction conditions, and since almost no side reactions occur in the reaction, the method produces a high-purity product with fewer impurities and easy to be purified, achieving unexpected technical effects.

Abstract: The present invention relates to a “one-pot process” for preparing intermediate of antibody-drug conjugate. The preparation process provided by the present invention is simple in operation, and needs no such steps like concentration, washing and filtration of the intermediate reaction liquid, disposal of the organic waste liquid, and packaging and storage of the intermediate. The entire reaction system comprises only one separation and purification treatment, saving costs for labor, equipment, venues, raw materials, etc., and greatly reducing the pollution to the environment. In addition, the “one-pot process” for preparing intermediate of antibody-drug conjugate of the present invention produces the intermediate of antibody-drug conjugate with higher yield. The “one-pot process” for preparing intermediate of antibody-drug conjugate provided by the present invention is more suitable for scale-up production.