(1R,1aS,6R,6aR)-1-Hydroxymethyl-1,1a,6,6a-tetrahydro-cyclopropa[a]indene-6-carboxylic acid

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

2-oxo-3,4-benzobicyclo<3.1.0>hex-3-ene-6-endo-carboxylic acid

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