HIGHLY OXIDIZED gamma-LACTAM-CONTAINING NATURAL PRODUCTS: TOTAL SYNTHESIS AND BIOLOGICAL EVALUATION

gamma-Lactam is a ubiquitous structure found in the natural products. A number of highly oxidized gamma-lactam-containing natural products are produced by various fungi. These compounds often show a wide range of biological activities because their multiple internal reaction sites, which arise from the high oxidation state of the compounds, can react with biological nucleophiles. Due to their high reactivity and dense functionality, total syntheses of these molecules require strict control of the inherent reactivity and the appropriate design of synthetic intermediates. This review focuses on the recent total syntheses of some highly oxidized gamma-lactam-containing natural products, including fused bicyclic (epolactaene, NG-391, lucilactaene, L-755,807), spirocyclic (azaspirene, pseurotin A, E, and F-2, cephalimysin A-C, FD-838, and berkeleyamide D), and tricyclic (rubrobramide and talaramide A) skeletons, and on the structure-activity relationship studies of related molecules.