Synonyms: [1R,2E,4S,(+)]-2-[(E)-2-Butenylidene]-1,3,3-trimethyl-7-oxabicyclo[2.2.1]heptane;[1R,4S,(+)]-2-[(1E,2E)-2-Buten-1-ylidene]-1,3,3-trimethyl-7-oxabicyclo[2.2.1]heptane;[1R,4S,(+)]-2-[(1E,2E)-2-Butene-1-ylidene]-1,3,3-trimethyl-7-oxabicyclo[2.2.1]heptane;[2S,5R,6E,8E,(+)]-2,5-Epoxy-6,8-megastigmadiene