Tadao Asami, Katsuhiko Sekimata, Jing Ming Wang, Koichi Yoneyama, Yasutomo Takeuchi and Shigeo Yoshida
[1,2-13C2]ABA, which is designed as a stable and pure internal standard for GC/MS analysis, is synthesized through the Witting reaction of 1-hydroxy-4-keto-α-ionone with carbomethoxymethylenetriphenylphosphorane prepared from [1,2-13C2]bromoacetic acid followed by saponification of the product methyl [1,2-13C2]ABA.