L-(+)-Cysteine → 3-Acetyl-2-(2-carboxyphenyl)-4-thiazolidinecarboxylic acid

Participants

Reaction Conditions

Reaction Steps

A solution of 6 of 2-carboxybenzaldehyde and 4.8 g of cysteine in 100 ml of water was stirred for 15 minutes. After adding 10 g of K2CO3, the solution was cooled to 0° C. and a solution of 8 g of acetic anhydride in THF was added. After everything had been added, the solution was stirred for a further 15 minutes at 0° C. and then for 1 hour at room temperature. The solution was concentrated under reduced pressure in order to evaporate THF, acidified to pH 1-2 with sulphuric acid and extracted with ethyl acetate. After drying over MgSO4 and evaporation of the solvent, the residue was crystallised from ethyl acetate/diethyl ether. Yield 22%.

Provenance & Evidence