Ampilectane and serrulatane natural products are structurally and stereochemically complex compounds that display various potent pharmacological activities ranging from anti-inflammatory to antituberculosis. A general synthetic route toward this family of natural products has been developed, which accomplished a number of amphilectane and serrulatane natural products. The key step employed a stereoselective Cope rearrangement either promoted by gold catalysis or thermal conditions, while a regioselective gold-catalyzed 6-endo-dig cyclization was optimized to afford a precursor. The preparation of the chiral β-ketoester as a starting material was established via an optimized asymmetric 1,4-addition followed by trapping with Mander's reagent, and this initially installed stereogenic center provided good control in the subsequent introduction of all the other stereocenters. A rarely investigated one-pot conversion of α-pyrone into phenol was also examined to enable the syntheses. DFT calculations explain the high stereoselectivity of the Cope rearrangement of the intermediate that eventually led to amphilectolide and caribenol A.
A concise and enantioselective total synthesis of the potent PI3K inhibitor (+)-wortmannin is described. A Pd-catalyzed cascade reaction was first developed to connect a synthon derived from Hajos-Parrish ketone to a furan moiety. The subsequent Friedel-Crafts alkylation of the β-position of a furan ring to an epoxide was optimized to establish the C10 quaternary center. (+)-Wortmannin was eventually accomplished by transformations following a late-stage oxidation of the furan allylic position. Kinome profiling and in vitro enzymatic assays were performed on 17-β-hydroxy-wortmannin and an epoxide analogue.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.