thionyl chloride in tetrahydrofuran T=4 - 20°C; 5.5 h; Inert atmosphere;

1: lithium chloride; lithium hydroxide hydrate; aluminum oxide / water / 5 h / -20 - -10 °C / pH 9.5 - 10.2 / |Inert atmosphere 2: sodium hydroxide / tetrahydrofuran / 2 h / 2 - 10 °C / |Inert atmosphere 3: potassium tert-butylate / tetrahydrofuran / 18 h / 20 °C / |Inert atmosphere 4: thionyl chloride / tetrahydrofuran / 5.5 h / 4 - 20 °C / |Inert atmosphere View Scheme

1: sodium hydroxide / tetrahydrofuran / 2 h / 2 - 10 °C / |Inert atmosphere 2: potassium tert-butylate / tetrahydrofuran / 18 h / 20 °C / |Inert atmosphere 3: thionyl chloride / tetrahydrofuran / 5.5 h / 4 - 20 °C / |Inert atmosphere View Scheme

1: imidazole / dimethylformamide; ethyl acetate / 0 - 20 °C 2: HCO2NH4 / Pd/C / methanol / 50 °C View Scheme

1: (2S,3S,5S)-2-(2,6-dimethylphenoxyacetyl)amino-3-hydroxy-5-amino-1,6-diphenylhexane With 1H-imidazole in ethyl acetate T=20°C; 2: 2S-(1-tetrahydro-pyrimid-2-onyl)-3-methyl butanoyl chloride in ethyl acetate; N,N-dimethyl-formamide T=0 - 20°C; 13 h;

1H-imidazole in ethyl acetate; N,N-dimethyl-formamide T=0 - 20°C; Inert atmosphere; Reagent/catalyst;