Hydrochloric Acid → (-)-2-[(2S)-2-[[(2R)-2-hydroxy-2-(4-hydroxy-3-hydroxymethylphenyl)ethyl]amino]-1,2,3,4-tetrahydronaphthalen-7-yloxy]-N,N-dimethylacetamide

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Reaction Steps

(-)-2-[(2S)-2-[[(2R)-2-(2,2-Dimethylbenzo[1,2-d]-1,3dioxan-6-yl)-hydroxyethyl]amino]-1,2,3,4-tetrahydronaphthalen-7-yloxy]-N,N-dimethylacetamide (192 mg) was dissolved in 3.8 ml of 1,2-dimethoxyethane, 4.2 ml of 1 N hydrochloric acid was added to the solution with stirring under ice-cooling, and the mixture was subjected to 2 hours of reaction at room temperature. The reaction solution was neutralized by adding an aqueous saturated sodium bicarbonate solution and then concentrated to dryness under reduced pressure. Tetrahydrofuran and ethanol were added to the resulting residue and insoluble materials were removed by filtration. The resulting filtrate was concentrated under reduced pressure, and the resulting residue was purified by aminopropylated silica gel medium pressure liquid column chromatography (eluent: ethyl acetate/ethanol=5/1) and then recrystallized from methanol to give 142 mg of (-)-2-[(2S)-2-[[(2R)-2-hydroxy-2-(4-hydroxy-3-hydroxymethylphenyl)ethyl]amino]-1,2,3,4-tetrahydronaphthalen-7-yloxy]-N,N-dimethylacetamide (Compound 6) having a melting point of 175 to 176° C.

Provenance & Evidence