A Most Recent Approach for the Stereoselective Synthesis of (+)epiCytoxazone

Discovery of the biological potentialities of cytoxazone by Kakeya’s research group has leveraged the
development of studies aimed at the synthesis of this compound. The stereoselective total synthesis
of (+)-epi-cytoxazone was performed satisfactorily in 8 steps, in 17% overall yield, via a novel route
from 2,3-O-(3-pentylidene)-(R)-glyceraldehyde. The bulky group alkene-ketal allowed intramolecular
control of the target molecule’s asymmetric centers in the dihydroxylation step by promoting the
approach of OsO4 to the face opposite to that of the ketal group. In this study, the authors proposed
that 5-epi-cytoxazone (1) may be prepared by an N,O-heterocyclization reaction of the corresponding
amino alcohol (8) in the last step of the synthesis.