| abstract |
An antibody-drug conjugate having a cyclic benzylidene acetal linker represented by formula (1) or formula (2), wherein Y is an antibody; D is a drug; R 1 and R 6 are each independently a hydrogen atom or a hydrocarbon group; R 2 , R 3 , R 4 and R 5 are each independently an electron-withdrawing or electron-donating substituent or a hydrogen atom; s is 1 or 2, t is 0 or 1, and s+t is 1 or 2; w is an integer of 1 to 20; and Z 1 and Z 2 are each independently a selected divalent spacer: |