6-endo-(hydroxymethyl)-2-exo-methyl-3,4-benzobicyclo<3.1.0>hex-3-ene-2-endo-carboxylic acid

6-exo-methyl-4-oxa-7,8-benzotricyclo<4.3.0.02,9>non-7-ene-3,5-dione

4-oxa-6,7-benzotricyclo<3.3.0.02,8>oct-6-en-3-one

6-exo-methyl-4-oxa-7,8-benzotricyclo<4.3.0.02,9>non-7-en-5-one

dimethyl 2-exo-methyl-3,4-benzobicyclo<3.1.0>hex-3-ene-2-endo,6-endo-dicarboxylate