Preparation of phosphinodipeptide analogs as building blocks for pseudopeptides synthesis

A simple and effective preparation of phosphinodipeptides, in good overall yields, has been developed. This one pot procedure, allowing the variation of the substituents in α and/or β position to the phosphorus atom and also in α position to the nitrogen atom, consists in the addition of alkyl hypophosphites to imines, followed by Michael-addition on acrylates. To show the value of phosphinodipeptides analogs 1 as synthetic intermediates, selective deprotections of the three functional groups are described.