As an antitumor drug which is excellent in terms of antitumor effect and safety and has an excellent therapeutic effect, there is provided an antibody-drug conjugate in which an antitumor compound represented by the following formula is conjugated to an anti-HER2 antibody via a linker having a structure represented by the formula: L1-L2-LP-NH-(CH2)n1-La-Lb-Lc or -L1-L2-LP-wherein the anti-HER2 antibody is connected to the terminal L1, and the antitumor compound is connected to the terminal Lc or LP with the nitrogen atom of the amino group at position 1 as the connecting position.
The 15N NMR spectra of a series of derivatives of 2‐amino‐2‐deoxy‐β‐D‐glucopyranose and dipeptides or secondary amines were recorded. In the dipeptide derivatives the chemical shift of nitrogen atom N‐1 (linked to sugar) is essentially unchanged and the shifts of nitrogen atoms N‐3 and N‐6 are determined by the nature of the R1 and R2 substituents at C‐α carbon of the amino acid unit. The highest shielding