| 摘要 |
To provide a hydrophilic polymer derivative having an acetal linker whose hydrolysis rate at pH of a weakly acidic environment in the living body can be accurately controlled, and which does not liberate a low molecular weight substance other than the hydrophilic polymer chain and the drug or the like connected, more specifically, a low molecular weight aldehyde, at the time of hydrolysis. The present invention relates to a hydrophilic polymer derivative having a cyclic benzylidene acetal linker represented by the following formula (1):
wherein 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; X 1 is a chemically reactive functional group; P is a hydrophilic polymer; s is 1 or 2, t is 0 or 1, and s + t is 1 or 2; w is an integer of 1 to 8; and Z 1 and Z 2 are each independently a selected divalent spacer. |
