6-methyl-4-oxohept-5-enal

(1S,2S,5R)-1-(prop-1-en-2-yl)-6-oxabicyclo[3.1.0]hexan-2-ol

3-((1S,2R,5S)-4,4-dimethyl-3-oxo-8-(propan-2-ylidene)bicyclo[3.2.1]oct-6-en-2-yl)propanal

2-methyl-3,7-dioxoheptan-2-yl acetate

3-((1R,2S,5S)-4,4-dimethyl-3-oxo-8-oxabicyclo[3.2.1]oct-6-en-2-yl)propanal