Hydrochloric Acid → 4-[6-(Cyclopentyloxycarbonyl)amino-2,3-dihydrobenz-1,4-oxazin-4-ylmethyl]-3-methoxybenzoic acid

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Reaction Steps

Lithium hydroxide monohydrate (0.267 g.) was added as a solid to a stirred solution of methyl 4-[6-(cyclopentyloxycarbonyl) amino-2,3-dihydrobenz-1,4-oxazin-4-ylmethyl]-3-methoxybenzoate (0.7 g.) in methanol (15 ml.) and water (2 ml.). The mixture was stirred for 12 hours then diluted with water and acidified to pH 3.35 with 3M hydrochloric acid. The precipitate which formed was isolated by filtration, washed with water and crystallized from methanol to give the title compound as a solid (0.457 g., 67%), m.p. 221°-222° C.

Provenance & Evidence