Compounds and compositions for treating neurodegenerative diseases are described. The compounds include a therapeutic agent covalently linked with huperzine or an analog thereof through a linker. Methods of preparing the compounds are described. Methods of treating a neurodegenerative disease by administering compounds and compositions including a therapeutic agent covalently linked with huperzine or an analog thereof are described. Methods for delivering a therapeutic agent by administering the therapeutic agent covalently linked to huperzine or an analog thereof are described.