Fig. 1.

Long-chain aliphatic aldehydes are produced during various metabolic processes. A: Schematic representation of aldehyde production in mammals during various enzymatic reactions, such as microsomal oxidation of long-chain alcohols, lysosomal degradation of prenylated proteins, peroxisomal α-oxidation of 3-methyl-branched fatty acids and 2-hydroxy long-chain fatty acids, attack of plasmalogens by MPO-derived hypochlorous acid, and microsomal breakdown of phosphorylated sphingoid bases. Double black arrows point to multiple steps. B: Scheme for the Hantzsch reaction.