for the following products
(S)-1-(tert-Butoxycarbonyl)-2-methylpyrrolidine-2-carboxylic acid | Boc-alpha-Me-L-Pro-OH | N-alpha-tert-Butyloxycarbonyl-alpha-Methyl-L-proline | N-Boc-alpha-Methyl-L-proline and (2S)-2-Methyl-1,2-pyrrolidinedicarboxylic acid 1-(1,1-dimethylethyl) ester