1: With 4-methyl-morpholine in 1,4-dioxane; water T=0 - 25°C; 22 h; 2: With hydrogenchloride in water T=0°C; pH=1;

hydrogenchloride in sodium hydroxide

lithium hydroxide hydrate in 1,4-dioxane; water T=20°C; 2.5 h;

1: NaHCO3 2: 45 percent / LDA / tetrahydrofuran / 20 °C View Scheme

1: (S)-2-Amino-4-chloro-1-((1S,5R,7R)-10,10-dimethyl-3,3-dioxo-3λ6-thia-4-aza-tricyclo[5.2.1.01,5]dec-4-yl)-butan-1-one; hydrochloride With lithium hydroxide in tetrahydrofuran; water 20 h; 2: di-tert-butyl dicarbonate With lithium hydroxide in diethyl ether; water 20 h;

1: N-(tert-Butoxycarbonyl)-(S)-(-)-2-azetidinecarboxylic acid With 4-methyl-morpholine; isobutyl chloroformate in tetrahydrofuran T=-10 - 25°C; 4 h; 2: methanol in tetrahydrofuran T=18 - 25°C; 18 h;