	US 12,187,688 B2
	Crystal form of tetramethylpyrazine nitrone, preparation method and use thereof
Wei Liu, Guangzhou (CN); Yewei Sun, Guangzhou (CN); and Yuqiang Wang, Guangzhou (CN)
Assigned to GUANGZHOU MAGPIE PHARMACEUTICALS CO., LTD., Guangzhou (CN)
Appl. No. 17/600,915
Filed by GUANGZHOU MAGPIE PHARMACEUTICALS CO., LTD., Guangdong (CN)
PCT Filed Jul. 31, 2019, PCT No. PCT/CN2019/098724 § 371(c)(1), (2) Date Oct. 1, 2021, PCT Pub. No. WO2020/199440, PCT Pub. Date Oct. 8, 2020.
Claims priority of application No. 201910255805.3 (CN), filed on Apr. 1, 2019.
Prior Publication US 2022/0153707 A1, May 19, 2022
Int. Cl. C07D 241/12 (2006.01); A61K 31/4965 (2006.01)

CPC C07D 241/12 (2013.01) [C07B 2200/13 (2013.01)]

10 Claims

1. A crystal form A of tetramethylpyrazine nitrone (TBN) wherein the crystal form A is characterized by an X-ray powder diffraction (XRPD) pattern having peaks at degrees 2θ of: 10.60±0.2, 11.03±0.2, 15.31±0.2, 15.55±0.2, 17.14±0.2, 17.93±0.2, and 23.81±0.2.