Large-scale asymmetric synthesis of novel sterically constrained 2′,6′-dimethyl- and α,2′,6′-trimethyltyrosine and -phenylalanine derivatives via alkylation of chiral equivalents of nucleophilic glycine and alanine

1. Soloshonok, V.A.
2. Tang, X.
3. Hruby, V.J.