methyl 17-cyano-3,6-dimeth-oxy-4,5α-ep-oxy-6,14-endo-ethenomorphinan-7-carboxyl-ate), C(23)H(24)N(2)O(5), the dihydro-furan ring adopts a twist conformation, while the piperidine ring is in a chair conformation. The benzene-fused cyclo-hexene ring adopts an envelope conformation. An intra-molecular C-H⋯O hydrogen bond is observed. Inter-molecular C-H⋯N and C-H⋯O hydrogen bonds form C(5) chains along the a and b axes, respectively, and together they form a three-dimensional network.