The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 04, 2009
Filed:
Apr. 09, 2003
Kaoru Okamoto, Hyogo, JP;
Naoharu Nishimura, Hyogo, JP;
Akira Ishii, Hyogo, JP;
Nippon Zoki Pharmaceutical Co., Ltd., Osaka, JP;
Abstract
Conventional I-form crystals of 5-hydroxy-1-methylhydantoin contain, remaining therein in a considerable amount, the organic solvent used in a purification step. In contrast, in II-form crystals, the amount of the organic solvent remaining therein is smaller than the detection limit. Namely, the II-form crystals contain substantially no residual organic solvent. The novel II-form crystals of 5-hydroxy-1-methylhydantoin obtained through recrystallization from water not only contain substantially no residual organic solvent, but also have a high bulk density and are hence advantageous for pharmaceutical preparation. They further have properties advantageous for production, such as low adhesion. The crystals are significantly useful as a material for medicines required to have high safety, such as drugs for renal insufficiency.