1: (2S)-N-{(2R)-2-[(dibenzylamino)methyl]propanoyl}camphorsultam With palladium on activated charcoal in tetrahydrofuran; methanol T=20°C; 2: With lithium hydroxide in tetrahydrofuran; water T=20°C; 3: di-tert-butyl dicarbonate With potassium carbonate in 1,4-dioxane 5 h; Further stages.;