A simple and effective method was proposed for the synthesis of new phosphinic peptides in free form, structural isosteres of the dipeptide components of beta-amyloid (Aβ42), potential inhibitors of zinc-metalloproteinases.

Phosphinic isosteres of leucylglycine and isoleucylglycine were obtained by amidoalkylation of (3-benzyloxy-3-oxopropyl)phosphonous acid bearing the structural isostere fragment of glycine benzyl ester in acetyl chloride. A three-component amide version of the Kabachnik–Fields reaction involving methyl (benzyl) carbamates and 2(3)-methylbutanals was studied. The reaction proceeded under the conditions of acylation of the starting (3-benzyloxy-3-oxopropyl)phosphonous acid and in situ generation of a bisacetyl derivative of the three-coordinated phosphorus, the formation of which was detected using NMR 31Р.

The amidoalkylation reactions of a phosphonous acid containing a structural isostere of leucine in acetyl chloride and(or) acetic anhydride were studied under conditions of acid catalysis. A two-component method for the synthesis of a phosphinic analogue of alanylleucine using ethylidenebis(benzylcarbamate) was proposed.