| abstract |
Provided is an antibody-drug complex having a linker of which the hydrolysis rate at a pH value in a weakly acidic in vivo environment can be controlled accurately. An antibody-drug complex having a cyclic benzylidene acetal linker, which is represented by formula (1) or (2). In the formulae, Y represents an antibody; D represents a drug; R1 and R6 independently represent a hydrogen atom or a hydrocarbon group; R2, R3, R4 and R5 independently represent an electron-withdrawing or electron-donating substituent or a hydrogen atom; s represents 1 or 2 and t represents 0 or 1, wherein the sum total of s and t is 1 or 2; w represents an integer of 1 to 20; and Z1 and Z2 independently represent a selected bivalent spacer. |