phthalic anhydride
1,2,3,4-Tetramethylbenzene
1,2,3,4-tetramethylnaphthalene
3,9b-Dihydro-9b-hydroxy-1,2,3a-trimethyl-3-methylencyclopenta
3,4,5,6,9,10,11,12-Octamethylpentacyclo<6.4.2.02,7.03,6.09,12>tetradeca-4,10,13-trien-2,7-dicarbonsaeureanhydrid