7-methyl-3-(trimethylsilylmethyl)octa-2,6-dienoic acid

ethyl 2,6,6-trimethylcyclohex-2-ene-1-carboxylate

甲基庚烯酮

(E)-3,7-二甲基-2,6-辛二烯醛

3-hydroxy-3,7-dimethyloct-6-enoic acid