Chemoenzymatic approaches to lycorine-type Amaryllidaceae alkaloids: total syntheses of ent -lycoricidine, 3- epi-ent -lycoricidine and 4-deoxy-3- epi-ent -lycoricidine

Abstract

The readily available and enzymatically derived cis-1,2-dihydrocatechol 4 has been elaborated, over 11 steps including an Overman rearrangement, into the non-natural enantiomer, (-)-1, of the alkaloid lycoricidine [(+)-1]. Related chemistries have provided analogues 18, 19, and 26.