Toward the Total Synthesis of Schinortriterpenoids: Construction of the All-cis-Substituted Cyclopropane Unit

Abstract

As a step toward a total synthesis of pre-schisanartanins and arisanlactones, we successfully synthesized a right fragment of Schisandra nortriterpenoids bearing a distorting all-cis-substituted cyclopropane from a chiral lactone. The key step in this synthesis was the diastereoselective construction of an all-cis-substituted cyclopropane through a Negishi coupling using an amide as a directing group.

Key words

cyclopropanes - nortriterpenoids - Negishi coupling - pre-schisanartanins - arisanlactones - diastereoselective synthesis

• References and Notes

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