This 3-hydroxydodecanoic acid methyl ester is a high purity standard that is useful for the investigation of disorders and diseases. Polyhydroxyalkenoates, polyesters produced by bacteria fermentation, are used for carbon and energy storage and are of interest in studies regarding their synthesis, properties and mechanisms. Medium chain-length polyhydroxyalkenoate monomers such as 3-hydroxydodecanoic acid may have pharmaceutical properties. The biologically natural chiral (R)-3- hydroxydodecanoic acid is an intermediate in fatty acid biosynthesis. 3-Hydroxydodecanoic acid is the major fatty acid in some lipopolysaccharides.1 3-hydroxy fatty acids are used as biomarkers for fatty acid oxidative disorders of both the longand short-chain 3-hydroxy-acyl-CoA dehydrogenases.2,3