(6Z)-8-Methyl-6-nonenoic Acid Ethyl Ester-d5 is an isotope analog of (6Z)-8-Methyl-6-nonenoic Acid Ethyl Ester. (6Z)-8-Methyl-6-nonenoic Acid Ethyl Ester is an ethyl analog of (6Z)-8-Methyl-6-nonenoic Acid, which is used in the synthesis of Capsaicin analogues, useful for their anti-tumor activity.