The title compound, ,8-didehydro-4,5-epoxy-17-methylmorphinan-3,6-diyl
diacetate, C21H23NO5, was crystallized from a solution of its hydroch
loride and sodium acetate, Unlike prior reports in which crystals were
hexagonal shaped (orthorhombic) and in space group P2(1)2(1)2(1), the
crystals in the present determination grew as large prisms (monoclini
c) and were in space group P2(1).