Alfa-form crystal of an acetanilide derivative

摘要

To provide novel crystals useful as an ingredient for the production of a diabetes remedy. The invention is concerned with alpha -form crystal and beta -form crystal of (R)-2-(2-aminothiazol-4-yl)-4'-Ä2-Ä(2-hydroxy-2-phenylethyl)aminoÜethylÜacetanilide. The alpha -form crystal does not exhibit hygroscopicity and has stability such that it can be used as a medicine, and is useful for mass synthesis in the industrial production. The beta -form crystal does not relatively exhibit hygroscopicity and is also useful as a production intermediate of the alpha -form crystal.