1: N-tert-butyloxycarbonyl-α-(phenylsulfonyl)-4-methylbenzylamine With TMS-SnBu3; cesium fluoride in N,N-dimethyl-formamide T=20°C; 0.0833333 h; Inert atmosphere; 2: carbon dioxide in N,N-dimethyl-formamide T=100°C; P=7500.75 Torr; 3 h; Autoclave; 3: With hydrogenchloride in diethyl ether; water; N,N-dimethyl-formamide pH=2; Inert atmosphere;