Astellas Pharma Gmbh

Yu Iwakawa

Takashi Sugane

Takahiko Tobe

Ryo Mizoguchi

Yuji Awamura

Noritaka Hamada

Kuniyuki Sano

Takaaki Sakaida

Object Provided are &#x3b2;-form crystal, &#x3b3;-form crystal, and &#x3b1;-form crystal of a benzoxadiazole derivative, wherein a uniform crystal having sufficient qualities can be obtained with high reproducibility, and they can be anytime supplied as crystals of drug substance for use in producing pharmaceuticals, are particularly suitable for mass synthesis in industrial production, hardly exhibit hygroscopicity and have particularly excellent photo-resistance. Means for Resolution A solving means includes &#x3b2;-form crystal of 4-[3-isopropyl-5-(6-phenyl-3-pyridyl)-4H-1,2,4-triazol-4-yl]-2,1,3-benzoxadiazole, which shows an endothermic peak at 145 to 150&#xb0; C. according to a differential scanning calorimeter analysis (DSC analysis) and shows X-ray powder diffraction peaks at 9.8, 11.1, 12.8, 13.3, 17.1, 20.2, 21.2 and 22.3 in 2&#x3b8;(&#xb0;), and the like.

Crystals of benzoxadiazole derivative

Growing community of inventors

Tokyo, Japan

Yu Iwakawa