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US 2019/0194146 A1Published application
6-bromo-3-hydroxy-2-pyrazinecarboxamide crystal and method for producing same
AssigneeFUJIFILM Toyama Chemical Co., Ltd.
InventorsTetsuro UCHIDA, Sayuri Uehara, Takayoshi Tsuzuki, Yusuke Okubo, Yuta Kobayashi, Yu Koseki
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Abstract
The purpose of the present invention is to provide a method for producing 6-bromo-3-hydroxy-2-pyrazinecarboxamide in which the content ratio of impurities is reduced. This production method includes a step of obtaining 6-bromo-3-hydroxy-2-pyrazinecarboxamide crystal having diffraction angles expressed in degrees 2θ of 5.5, 20.1, 23.7, 26.7, 27.5, and 28.1° and/or diffraction angles expressed in degrees 2θ of 7.1, 21.4, 25.2, 25.7, 27.1, and 28.8° in powder X-ray diffraction.
Claims15
1:
- A method for producing 6-bromo-3-hydroxy-2-pyrazinecarboxamide, comprising:
- preparing a suspension including 3-hydroxy-2-pyrazinecarboxamide and a solvent;
- and
- adding bromine to the suspension obtained from the preparing of the suspension,
- wherein a content ratio of water included in the suspension is less than 5% (w/w) relative to 3-hydroxy-2-pyrazinecarboxamide, and a content ratio of 3-hydroxy-2-pyrazinecarboxamide included in 6-bromo-3-hydroxy-2-pyrazinecarboxamide is less than 300 ppm.
2 more elements
2:
- The method of claim 1, further comprising:
- obtaining a crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide having diffraction angles of 5.5, 20.1, 23.7, 26.7, 27.5, and 28.1° in terms of 2θ in powder X-ray diffraction.
3:
- The method of claim 1, further comprising:
- obtaining a crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide having diffraction angles of 5.5, 20.1, 23.7, 26.7, 27.5, and 28.1° in terms of 2θ in powder X-ray diffraction;
- reacting the crystal with a base, to obtain a salt of 6-bromo-3-hydroxy-2-pyrazinecarboxamide;
- and
- reacting the salt with an acid, to obtain a crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide having diffraction angles of 7.1, 21.4, 25.2, 25.7, 27.1, and 28.8° in terms of 2θ in powder X-ray diffraction.
2 more elements
4:
- The method of claim 3, wherein the base is at least one base selected from the group consisting of sodium hydroxide, sodium hydrogen carbonate, and potassium hydroxide, and the acid is at least one acid selected from the group consisting of hydrochloric acid, nitric acid, and sulfuric acid.
5:
- The method of claim 1, wherein 3-hydroxy-2-pyrazinecarboxamide in the preparing the suspension is an anhydrous form of 3-hydroxy-2-pyrazinecarboxamide.
6:
- A method for producing 6-bromo-3-hydroxy-2-pyrazinecarboxamide, comprising:
- reacting a crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide having diffraction angles of 5.5, 20.1, 23.7, 26.7, 27.5 and 28.1° in terms of 2θ in powder X-ray diffraction with a base to obtain a salt of 6-bromo-3-hydroxy-2-pyrazinecarboxamide;
- and
- reacting the salt with an acid to obtain a crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide having diffraction angles of 7.1, 21.4, 25.2, 25.7, 27.1 and 28.8° in terms of 2θ in powder X-ray diffraction.
1 more element
7:
- The method of claim 6, wherein the base is at least one base selected from the group consisting of sodium hydroxide, sodium hydrogen carbonate and potassium hydroxide, and the acid is at least one acid selected from the group consisting of hydrochloric acid, nitric acid and sulfuric acid.
8:
- A crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide, having diffraction angles of 5.5, 20.1, 23.7, 26.7, 27.5 and 28.1° in terms of 2θ in powder X-ray diffraction, wherein a content ratio of 3-hydroxy-2-pyrazinecarboxamide included in 6-bromo-3-hydroxy-2-pyrazinecarboxamide is less than 300 ppm.
9:
- A crystal of 6-bromo-3-hydroxy-2-pyrazinecarboxamide, having diffraction angles of 7.1, 21.4, 25.2, 25.7, 27.1 and 28.8° in terms of 2θ in powder X-ray diffraction, wherein a content ratio of 3-hydroxy-2-pyrazinecarboxamide included in 6-bromo-3-hydroxy-2-pyrazinecarboxamide is less than 300 ppm.
10:
- An anhydrous form of 3-hydroxy-2-pyrazinecarboxamide.
11:
- An anhydrous crystal of 3-hydroxy-2-pyrazinecarboxamide, having diffraction angles of 11.9, 13.2, 23.9 and 26.7° in terms of 2θ in powder X-ray diffraction.
12:
- 6-Fluoro-3-hydroxy-2-pyrazinecarboxamide, wherein a content ratio of 3-hydroxy-2-pyrazinecarboxamide is less than 5 ppm.
13:
- The method of claim 2, wherein 3-hydroxy-2-pyrazinecarboxamide in the preparing the suspension is an anhydrous form of 3-hydroxy-2-pyrazinecarboxamide.
14:
- The method of claim 3, wherein 3-hydroxy-2-pyrazinecarboxamide in the preparing the suspension is an anhydrous form of 3-hydroxy-2-pyrazinecarboxamide.
15:
- The method of claim 4, wherein 3-hydroxy-2-pyrazinecarboxamide in the preparing the suspension is an anhydrous form of 3-hydroxy-2-pyrazinecarboxamide.