Systemic Study on the Biogenic Pathways of Yezo’otogirins: Total Synthesis and Antitumor Activities of (±)-Yezo’otogirin C and Its Structural Analogues

A systematic
study of the biomimetic pathways to yezo’otogirin
C under aerobic and anaerobic conditions has been investigated, and
both are found to be feasible pathways to the natural product depending
on the physiological conditions. Because of the lower activation energy,
the aerobic process would be more favorable when the in vivo oxygen
level is high. In the course of this study, a highly efficient synthetic
route to (±)-yezo’otogirin C has been established in four
steps (31% overall yield) from a readily available compound without
using any protecting groups. The natural product and its structural
analogues exhibited antitumor activities against several human cancer
cell lines and appeared to arrest cell cycles in different phases.