https://www.selleckchem.com/ Azelaic acid (AzA) is a dicarboxylic acid naturally occurring in various grains having anti-inflammatory and anti-oxidation properties. Recently, AzA is shown to reduce high-fat diet-induced adiposity in animals. However, its physiological role in lipid metabolism and aging in various environmental stresses is unknown. Using C. elegans as an invertebrate animal model, we demonstrate that AzA suppresses fat accumulation with no effect on lifespan at normal temperatures. Moreover, AzA promotes lifespan at low temperatures by elevation of unsaturated long-chain fatty acids and expression of genes in fatty acid desaturation. We further find that genes encoding fatty acid desaturases such as fat-1, fat-5, fat-6, and fat-7 are crucial for the lifespan-extending effect of AzA at low temperature. Taken together, our results suggest that AzA promotes adaption to low temperature in C. elegans via shifting fatty acid profile to unsaturated long-chain fatty acids. Taken together, our results suggest that AzA promotes adaption to low temperature in C. elegans via shifting fatty acid profile to unsaturated long-chain fatty acids.A series of mono and disubstituted 2,3-dihydroquinazolin-4(1H)-ones (DHQZs) were synthesized and the electronic and steric effects of the C2- and N3-substitutions on the retention or elimination of the C2-substitution by exposing them to the ultraviolet light were investigated. Electron transfer from photo-excited dihydroquinazolinones to chloroform solvent is proposed, in which both lone pairs on the N1- and N3-atoms can be involved in this process. The extent of the N1- and N3-atoms contributions in this electron-transfer process and also the retention or elimination of the C2-substitutions are dependent on the nature and steric hindrance of both C2- and N3-substitutions. The experimental results are supported by the computational studies. Photoinduced electron-transfer reaction of a series of mono and disubstituted 2,3- dih