Bortezomib Prodrugs

Disclosed herein are compounds of Formula (I) or (II). The compounds include an agent (e.g., pharmaceutical agent, cosmetic agent, or nutraceutical agent) through a linker that includes a boronic ester moiety in the backbone of the linker. The compounds may be monomers. Also provided are polymers prepared by polymerizing the monomers. The polymers may be useful for delivering the agent to a subject, tissue, biological sample, or a cell. Also provided are methods of preparing the polymers, compositions and kits comprising the polymers, and methods of use (e.g., use in delivering the agent, treating a disease, preventing a disease, diagnosing a disease) involving the polymers or compositions. The structure of the boronic ester moiety may be fine tuned so that the properties related to delivery to a subject, biological sample, tissue, or cell may be fine tuned.