Expedient Synthesis of Natural (S)-Sinefungin and of Its C-6'-Epimer.

Sinefungin 1a and 6-epi-sinefungin 1b have been prepared from adenosine and L-aspartic acid. The key step in the synthesis was the coupling of the radical derived from 14 with the unsaturated amide 13. The latter was obtained by a radical reaction from L-aspartic acid and olefin 11. Thus the carbon skeleton is constructed in two radical coupling reactions.