Chemoselective and Diastereoconvergent Cu(II)-Catalyzed Aerobic Endoperoxidation of Polycarbonyls.

The diastereoconvergent synthesis of spirocyclic endoperoxides using a Meldrum's acid scaffold has been accomplished by employing readily available feedstock chemicals. Site selective C-H oxidation of the bis(ß-dicarbonyl) substrates was performed using elemental oxygen as the stoichiometric oxidant and a commercial Cu(II) catalyst. Sequential hydrogenolysis and ionic reduction of these endoperoxides provided fully substituted tetrahydrofurans in high yields and diastereoselectivity.

ICI 56,780 Optimization: Structure-Activity Relationship Studies of 7-(2-Phenoxyethoxy)-4(1H)-quinolones with Antimalarial Activity.

Though malaria mortality rates are down 48% globally since 2000, reported occurrences of resistance against current therapeutics threaten to reverse that progress. Recently, antimalarials that were once considered unsuitable therapeutic agents have been revisited to improve physicochemical properties and efficacy required for selection as a drug candidate. One such compound is 4(1H)-quinolone ICI 56,780, which is known to be a causal prophylactic that also displays blood schizonticidal activity against P. berghei. Rapid induction of parasite resistance, however, stalled its further development. We have completed a full structure-activity relationship study on 4(1H)-quinolones, focusing on the reduction of cross-resistance with atovaquone for activity against the clinical isolates W2 and TM90-C2B, as well as the improvement of microsomal stability. These studies revealed several frontrunner compounds with superb in vivo antimalarial activity. The best compounds were found to be curative with all mice surviving a Plasmodium berghei infection after 30 days.