Identification of intermediates involved in the biosynthetic pathway of 3-mercaptohexan-1-ol conjugates in yellow passion fruit (Passiflora edulis f. flavicarpa)

► New synthetic strategy for the preparation of Glu-Cys-3MH and Cys-Gly-3MH. ► The three missing stages leading to the S-cysteinylated precursor were identified. ► Two intermediates found between S-glutathionyl and S-cysteinyl 3-mercaptohexan-1-ol. ► Demonstrating that the plant is capable of activating both metabolic routes.