Synthesis of α-aminophosphonic and α-aminophosphinic acids and derived dipeptides from 4-acetoxyazetidin-2-ones

Abstract

4-Oxoazetidin-2-ylphosphonates and 4-oxoazetidin-2-ylphosphinates, obtained from the Arbusov reactions of 4-acetoxyazetidin-2-one and 4α-acetoxy-3β-phthalimidoazetidin-2-one with a variety of phosphites and phosphonites, were hydrolysed to β-phosphono- and β-phosphino-β-alanine derivatives which were converted into alanyl dipeptides; conditions for the sequential removal of protecting groups for carboxylic acids, phosphonic acids, and amines were investigated.