Pharmacologically interesting lycorines were obtained by a short, effi
cient method based on an intramolecular Diels-Alder reaction between a
n alpha-pyrone and an alkyne, followed by loss of CO2 in a retro Diels
-Alder reaction. The cyclization precursors (pyrones 9) were obtained
in good yields in two or three steps from the corresponding homophthal
ic acid or anhydride.