Utilizing <i>N</i>‐Hydroxylamine‐Based Active Esters for the Synthesis of Oseltamivir Amide Derivatives

Abstract Functionalizing and derivatizing pharmaceuticals are essential for preparing new potentially active compounds. This work shows how active esters derived from oseltamivir carboxylate can be useful synthetic tools for accessing various amide derivatives of oseltamivir. Six hydroxylamine active esters were synthesized directly from oseltamivir carboxylate, and their utility in preparing amide derivatives was evaluated. Succinimide ester 5 e was the most efficient in terms of its preparation and in synthesizing oseltamivir derivatives.