Synthesis of gamma-methyl-L-leucine (neopentylglycine, Neo) and derivatives suitable for peptide synthesis.

The modified Strecker synthesis of Patel & Worsley was combined with an enzymatic deamidation in the final step, to produce the title compound. The amino acid is a member of the family of the "fat" amino-acids with high lipophilicity and space-filling properties, as estimated by its Hansch hydrophobicity constant pi and its Charton steric parameter v. It can be used for qualitative and quantitative studies of structure-activity relationships in biologically active peptides. Three of its derivatives suitable for peptide synthesis are also described.