13046-69-0 2,4-Hexadienoic acid, 2-hydroxy-5-methyl-6-oxo- 2-Hydroxy-5-methyl-6-oxo-2,4-hexadienoic acid 2-Hydroxy-5-methylmuconic semialdehyde Sorbic acid, 5-formyl-2-hydroxy- alpha-Hydroxy-delta-methylmuconic epsilon-semialdehyde