The absolute configuration of boschnaloside and the chemical conversion of genipin into boschnaloside.

Abstract

The absolute configuration of boschnaloside was established by chemical correlation of asperuloside tetraacetate with boschnaloside tetraacetate. During this work it was also found that catalytic reduction of asperuloside tetraacetate gave either of the two C-8 epimers (4) and (5), depending upon the kind of catalyst used, PtO2 or Pd-C. The absolute structure of boschnaloside was also confirmed by its degradation to 3(R)-cis, cis-boschnialinic acid. Finall, conversion of genipin into boschnaloside was also achieved.