| abstract |
Disclosed is a bio-related substance modified by a multifunctionalized polyethylene glycol derivative (formula 1). The substance has an H-shaped structure and comprises one linear core LPEG and four PEG branch chains, where n 1 , n 2 , n 3 , and n 4 respectively are the degrees of polymerization of the branch chains, U 1 and U 2 are trivalent branching groups connecting the LPEG to two of the PEG branch chains, F 1 and F 2 contain a functional group or a protected form R 01 thereof, and the number of R 01 is one or more. Any one linking group in the molecule or any linking group formed with an adjacent heteroatom group can either remain stable or be degraded; any one PEG segment in the molecule discretely has polydispersity or monodispersity. various or multiple bio-related substances can be modified by one H-shaped molecule, the modified products are flexible in branching structure, provide high drug loading, optimizable pharmacokinetics and tissue distribution, and also can carry two bio-related substances of different functions, thus producing a fluorescence property or a targeting function. |