Synthesis and Antioxidant Evaluation of Enantiomerically Pure Bis-(1,2,3-triazolylmethyl)amino Esters from Modifiedα-Amino Acids

Abstract

The efforts for synthesis of enantiomerically pure bis-(1,2,3-triazolylmethyl)amino esters6are reported in good yields from anin situgeneratedα-azidomethyl ketone. Optimum experimental conditions were established for preparation ofα-halomethyl ketones10andα-N,N-dipropargylamino esters11, all derived fromα-amino acids. The starting materials reacted under conventional click chemistry conditions, revealing a specific reactivity of bromomethyl ketones over chloromethyl ketones. The antioxidant activity of compounds6was assayed by DPPH method. The compound6cwith an IC50of 75.57 ± 1.74 μg mL−1was the most active. Technically, this methodology allows the preparation of a combinatorial library of analogues with different structural characteristics depending on the nature of the modifiedα-amino acids employed in the synthesis.