dimethyl 1,4,5,6-tetramethylbicyclo[2.2.0]hexa-2,5-diene-2,3-dicarboxylate

dimethyl 4,7,8,9-tetramethyl-3a,4,7,7a-tetrahydro-1H-4,7-ethenoindene-5,6-dicarboxylate

3,4-二氯-1,2,3,4-四甲基环丁烯

1,2-Bis(nitromethyl)-3,4,5,6-tetramethylbenzene