CH3CO−CH3CH_3CO -CH_3CH3CO−CH3
CH3CH2−CHOCH_3CH_2-CHOCH3CH2−CHO
CH2=CH−CH2−OHCH_2=CH-CH_2 -OHCH2=CH−CH2−OH
CH3CH=CH−OHCH_3CH=CH -OHCH3CH=CH−OH
CH2=H−O−CH3CH_2=H - O-CH_3CH2=H−O−CH3
