Sodium Bicarbonate → sodium (5R,6S)-3-(2-acetamido-ethylthio)-6-(1-hydroxy-1-methylethyl)-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate

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Reaction Steps

A mixture of 5% palladium-charcoal (40.0 mg), water (0.96 ml) and dioxane (2.24 ml) was shaken for 30 minutes under hydrogen atmosphere (40 psi) at ambient temperature. The mixture was added to a solution of 4-nitrobenzyl (5R,6S)-3-(2-acetamidoethylthio)-6-[1-methyl-1-(4-nitrobenzyloxycarbonyloxy)ethyl]-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (40.0 mg) in a mixture of water (0.24 ml) and dioxane (0.56 ml), and shaken for 2 hours under hydrogen atmosphere (40 psi) at ambient temperature. The resulting mixture was added with 1% aqueous sodium hydrogen carbonate (0.522 ml) at 0° C. and filtered by using diatomaceous earth. The filtered cake was washed with water (3×5 ml) and the combined filtrates were concentrated, washed with ethyl acetate (3×20 ml) and evaporated in vacuo. The residue was dissolved in water (25 ml) containing sodium chloride (0.7 g) and chromatographed on a non ionic adsorption resin HP-20 (trademark, made by Mitsubishi Chemical Industries) (1.0×20 cm) eluting with a mixture of water and acetone (100:0 to 7:3, 200 ml). The fractions containing the product were combined and lyophilized to give sodium (5R,6S)-3-(2-acetamido-ethylthio)-6-(1-hydroxy-1-methylethyl)-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate (6.9 mg) as a white solid.

Provenance & Evidence