Comprehensive Summary Polymer functionalization is a powerful tool to prepare polymers with diverse structures without the need of synthesizing monomers or performing polymerization reactions. Polymers that are difficult to be synthesized using direct polymerization reactions can be accessed using polymer functionalization. We herein present Mitsunobu derivatization of poly(vinyl alcohol) (PVA) to convert the hydroxyl groups into diverse functional groups. Partial acetalation strategy is applied to improve solubility of the PVA derivatives in tetrahydrofuran, and more importantly, the acetals can act as protecting groups so that functionalized copolymers are produced. Diverse functions can be introduced into PVA derivatives by installing different functional groups. Transparent, colorless, flexible, and scalable UV-shielding membranes are conveniently prepared in one step using this method.
Four novel betulinic acid (BA) derivatives modified at the C-3 position were prepared by the Mitsunobu reaction and subsequently evaluated for antitumor activity against four common cancer cell lines in vitro. The results from the MTT assay revealed that the four tested compounds showed remarkable cytotoxic activity against four cancer cell lines, much better than BA. Western blotting results indicated that the four compounds, especially compound 2c , caused a significant up-regulation expression of the caspase-12 in CT26 cell. Our results showed that configuration inversions of chiral C-3 of BA could also produce BA derivatives with potent antitumor activity.
危险品化学品经营许可证（带存储）