Methods for crystallization of N-(1(s)-ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxyanhydride
AssigneeKaneka Corporation
InventorMasafumi Fukae
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Abstract
A crystallization is carried out by adding a solution of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxylic anhydride in a good solvent to an aliphatic hydrocarbon solvent while inhibiting the oil formation and scaling of said N-carboxylic anhydride. Further, a crystallization is carried out by adding an aliphatic hydrocarbon solvent sequentially to a solution of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxylic anhydride in a good solvent over not less than ¼ of an hour and at a temperature of not higher than 60° C.
Claims51
A method for crystallizing N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxylic anhydride
- comprising mixing a solution of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxylic anhydride in a good solvent with an aliphatic hydrocarbon solvent to crystallize said N-carboxylic anhydride,
- the solution of said N-carboxylic anhydride in the good solvent being added to the aliphatic hydrocarbon solvent to thereby effect crystallization while inhibiting an oil formation and scaling of said N-carboxylic anhydride wherein the good solvent is a halogenated hydrocarbon, an ether, a nitrile, an ester, a ketone or a mixed solvent thereof.
A method for crystallizing N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine N-carboxylic anhydride
- comprising adding an aliphatic hydrocarbon solvent to a solution of N-(1(S)-ethoxycarbonyl-3-phenylpropyl)-L-alanine-N-carboxylic anhydride in a good solvent to crystallize said N-carboxylic anhydride,
- the aliphatic hydrocarbon solvent being added sequentially over not less than ¼ of an hour and at a temperature of not higher than 60° C. to thereby inhibit an oil formation and scaling of said N-carboxylic anhydride wherein the good solvent is a halogenated hydrocarbon, an ether, a nitrile, an ester, a ketone or a mixed solvent thereof.
Dependencies are inferred from the claim text.