1: t-Boc-L-valine With 4-methyl-morpholine; isobutyl chloroformate in ethyl acetate T=0°C; Inert atmosphere; 2: O,N-dimethyl-hydroxylamine hydrochloride in ethyl acetate T=0 - 20°C; 48.25 h; Inert atmosphere;

1: N-t-butyloxycarbonyl-D-valine With 4-methyl-morpholine; isobutyl chloroformate in ethyl acetate T=0°C; Inert atmosphere; 2: O,N-dimethyl-hydroxylamine hydrochloride in ethyl acetate T=0 - 20°C; 48.25 h; Inert atmosphere;

N'-(3-dimethylaminopropyl)-N-ethylcarbodiimide in pyridine; dichloromethane Condensation;

1: tert-butyl 1-(methoxy(methyl)amino)-3-methyl-1-oxobutan-2-ylcarbamate With lithium aluminium tetrahydride in tetrahydrofuran T=20°C; 0.5 h; Inert atmosphere; 2: (1-Diazo-2-oxo-propyl)-phosphonic acid dimethyl ester in methanol T=0°C; 0.5 h; Inert atmosphere; 3: With potassium carbonate in methanol T=20°C; 15 h; Inert atmosphere;