Hydrochloric Acid → 1,3-Thiazol-5-ylmethyl N-((1S,2S,4S)-4-amino-1-benzyl-2-hydroxy-5-phenylpentyl)carbamate

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Reaction Steps

The product of Example 69A (6.43 g, 12.23 mmoles) was dissolved in 25 mL dioxane at room temperature under nitrogen atmosphere. To this stirred solution was added 20.25 mL of 4N HCl in dioxane, and after approximately 10 min thick precipitate formed. An additional 10 mL of dioxane was added to loosen up the slurry. This mixture was stirred for 1 h and then filtered. The filter cake of the product bis-HCl salt was washed with 20 mL dioxane, air dried, and then dissolved in 175 mL water. To this solution was added 175 mL ethyl acetate and the two phase mixture rapidly stirred. The pH of this mixture was adjusted to pH=10 by the dropwise addition of 3N NaOH to the rapidly stirred mixture. The organic layer was isolated, washed with brine (150 mL), and dried over Na2SO4. The solvent was removed to afford 5.18 g (99%) of the desired product as a clear oil. H1NMR (CDCl3) δ 8.81 (s, 1H), 7.87 (s, 1H), 7.35-7.05 (m, 10H), 5.33 (d, 1H, J=9.3 Hz), 5.28 (m,2H), 3.81 (m, 1H), 3.72 (m, 1H), 3.01 (m, 1H), 2.88 (m, 2.78 (dd, 1H, J=13.5, 5.1 Hz), 2.39 (dd, 1H, J=9.0, 4.5 Hz), 1.57-1.30 (m, 2H) 2H). ClMS m/z 426 (M+H)+.

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