Tetrabutylammonium 8-Hydroxy-5-methyloctanoate is an intermediate in the synthesis of 1,2-Cyclohexanedicarboxylic Acid Mono 4-Methyl-7-carboxy-heptyl Ester-d8 (C987317), which is labelled 1,2-Cyclohexanedicarboxylic Acid Mono 4-Methyl-7-carboxy-heptyl Ester (C987315) which is a possible metabolite of the di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH) monoester (MINCH).