Ring Opening of 6-Azabicyclo­[3.1.0]hex-3-en-2-ols in Water under Mild Conditions

The ring-opening reaction of α-hydroxycyclopenteno-aziridines (6-azabicyclo[3.1.0]hex-3-en-2-ols) was investigated in water and under physiological conditions (pH = 7.4) at 37 °C by using a range of carbon-, oxygen-, nitrogen-, and sulfur-containing nucleophiles such as azides, anilines, and thiols (aryl and alkyl thiols as well as cysteine and its derivatives), which provided the products in moderate to high isolated yields. The reactivity was also demonstrated in the bioconjugation of α-hydroxycyclopenteno-aziridine with the peptide hormone salmon calcitonin (sCT).