One-Step Semisynthesis Method of Spirocurcasone and Pyracurcasone from Curcusones A and B

High contents of curcusones A and
B and trace amounts of spiro­curcasone
exist in the roots of Jatropha curcas. Here, a one-step semi­synthesis method of spiro­curca­sone
and pyra­curca­sone was built, not only resulted an increased
yield of spiro­curca­sone but also produced pyra­curca­sone,
which exhibited greater cytotoxicity compared to curcusones A and
B. The plausible mechanism of the formation of pyra­curca­sone
was proposed, and the proposed biogenetic origin for spiro­curcasone
by Taglialatela-Scafati was confirmed.