Total syntheses of certain asperversiamides, linearly-fused and prenylated indole alkaloids

Abstract

Biogenetically patterned total syntheses of the prenylated indole alkaloids asperversiamides B, D, E, G and J as well as dihydrocarneamide A have been realised while a related synthesis of the racemic modification of the structure assigned to asperversiamide A suggests this is incorrect. The efficient oxidative rearrangement of (±)-asperversiamide D into the C8a′ epimer of asperversiamide C suggests this spiro-oxindole is likely to be a natural product-in-waiting as is ent-asperversiamide F, the co-product from the Stryker-type reduction of asperversiamide G.