10.1021/jo050388m
The study focuses on the total synthesis of lamellarins, a group of marine natural products with significant biological activities, using polymer-supported reagents. The researchers utilized four solid-supported reagents in the multistep synthesis process. Key chemicals included Amberlyst A-26 Br3-, polymer bound pyridine hydrobromide perbromide (PVPHP), and Amberlyst A-26 NaCO3-, which were used for selective keto R-bromination of ortho-substituted acetophenone derivatives to produce monobromination products. These products were then used in condensation reactions with benzyldihydroisoquinoline, mediated by Amberlyst A-26 NaCO3-. The synthesized 2H-pyrrole carbonates underwent intramolecular Friedel-Crafts transacylation and lactonization to provide the lamellarin skeleton. Amberlyst-15 was also used to mediate lactonization reactions, effectively combining two separate steps into one transformation. The purpose of these chemicals was to facilitate selective and efficient synthetic pathways for lamellarins, which are important for establishing structure-activity relationships and investigating their mechanisms of action, particularly in the context of cancer cell lines and multidrug-resistance.