5-羟基-2-戊酮

5-bromo-6-methyl-hept-5-en-2-one

3,4-dihydroxy-5-hydroxymethyl-tetrahydro-furan-2-carbaldehyde

6-methyl-3-oxo-2,3,4,5-tetrahydro-pyridazine-4-carboxylic acid ethyl ester