Two Diastereomeric Artificial Enzymes with Different Catalytic Activity



Two epimeric cyclodextrin-6-C-aldehydes were synthesised in 10 steps from β-cyclodextrin. The synthesis involved protection/partial deprotection, oxidation to a 6-aldehyde, olefination, dihydroxylation, selective protection of the secondary alcohol and oxidation. The two isomers catalysed theoxidation of aromatic amines by hydrogen peroxide but predominantly outside the cavity. Hydrolysis of aryl glycosides on the other hand was catalysed in a reaction followingMichaelis–Menten kinetics. The S isomer was a 5–20 times better catalyst than the R isomer, which was explained from models.