Orthogonal Design of a Water-Soluble meso-Tetraphenylethene-Functionalized Pillar[5]arene with Aggregation-Induced Emission Property and Its Therapeutic Application.

An orthogonal strategy was utilized for synthesizing a novel water-soluble pillar[5]arene (m-TPEWP5) with tetraphenylethene-functionalized on the bridged methylene group (meso-position) of the pillararene skeleton. The obtained macrocycle exhibit both the aggregation-induced emission (AIE) effect and interesting host-guest property. Moreover, it can be made to bind with a tailor-made camptothecin-based prodrug guest (DNS-G) to form AIE-nanoparticles based on host-guest interaction and the fluorescence resonance energy transfer process for fabricating a drug delivery system. This novel type of water-soluble AIE-active macrocycle can serve as a potential fluorescent material for cancer diagnosis and therapy. In addition, the present orthogonal strategy for designing meso-functionalized aromatic macrocycles may pave a new avenue for creating novel supramolecular structures and functional materials.