Chemical synthesis and structural elucidation of a new serotonin metabolite: (4R)-2-[(5′-hydroxy-1′H-indol-3′-yl)methyl]thiazolidine-4-carboxylic acid

A new serotonin (5-hydroxytryptamine) metabolite, (4R)-2-[(5′-hydroxy-1′H-indol-3′-yl)methyl]thiazolidine-4-carboxylic acid (5′-HITCA), was synthesized in 30% overall yield. The key step involved oxidation of protected 5-hydroxytryptophol using IBX followed by spontaneous cyclization with l-cysteine. The stereochemistry of condensation product thiazolidine-4-carboxylic acid was studied using NMR spectroscopy techniques.