Patents by Inventor Wenquan ZHU

Wenquan ZHU has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11519890
    Abstract: Disclosed is a detection method for N-nitrosodimethylamine (NDMA) impurities, comprising: (1) obtaining a test solution containing a sample to be tested; and (2) detecting the test solution by means of gas chromatography-mass spectrometry to determine the content of an N-nitrosodimethylamine impurity in the sample. The method provided in the present invention has a good separating effect, a wide linear range, a high sensitivity and a good method durability, and can detect the content of N-nitrosodimethylamine (NDMA) in the sample rapidly and effectively.
    Type: Grant
    Filed: July 10, 2018
    Date of Patent: December 6, 2022
    Assignee: ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD
    Inventors: Tan Xiao, Tianpei Huang, Jinsheng Lin, Qiang Zhou, Tong Wu, Danfeng Ye, Hong Cai, Wenquan Zhu, Wenbin Chen, Min Li
  • Patent number: 11434210
    Abstract: A method for synthesizing valsartan, comprising the steps of: synthesizing a valsartan methyl ester intermediate to obtain a reaction mixture of the valsartan methyl ester intermediate; diluting the reaction mixture by salt water or water, and then using a first extraction solvent to extract the valsartan methyl ester intermediate; adding alkali to an organic layer containing the valsartan methyl ester intermediate for hydrolyzing, removing the organic layer, regulating pH of a water layer to be acidic by using acid, using the first extraction solvent to extract, concentrating a part of solvent, or distilling the solvent to dryness, and then adding a new solvent; finally, crystallizing, filtering, and drying to obtain the valsartan.
    Type: Grant
    Filed: July 17, 2018
    Date of Patent: September 6, 2022
    Assignee: Zhejiang Huahai Pharmaceutical Co., Ltd
    Inventors: Xiaohui Zhou, Xiaoren Zhu, Yuanxun Zhu, Peng Dong, Peng Wang, Jinsheng Lin, Wenquan Zhu, Min Li
  • Publication number: 20210387971
    Abstract: Provided are a pregabalin lactam methylene dimer and a preparation method therefor. The method comprises the following steps: dissolving pregabalin in a reaction solvent, reacting same with an aldehyde in an acidic system and isolating the obtained target product pregabalin lactam methylene dimer. The preparation method for pregabalin lactam methylene dimer provided by the present application has a simple operation, a high product yield, a good purity and a low cost.
    Type: Application
    Filed: November 6, 2018
    Publication date: December 16, 2021
    Inventors: Jinsheng LIN, Xiaofei LIU, Dan LI, Jing WANG, Yue LI, Wenquan ZHU, Wenbin CHEN, Min LI
  • Publication number: 20210285920
    Abstract: Disclosed is a detection method for N-nitrosodimethylamine (NDMA) impurities, comprising: (1) obtaining a test solution containing a sample to be tested; and (2) detecting the test solution by means of gas chromatography-mass spectrometry to determine the content of an N-nitrosodimethylamine impurity in the sample. The method provided in the present invention has a good separating effect, a wide linear range, a high sensitivity and a good method durability, and can detect the content of N-nitrosodimethylamine (NDMA) in the sample rapidly and effectively.
    Type: Application
    Filed: July 10, 2018
    Publication date: September 16, 2021
    Inventors: Tan XIAO, Tianpei HUANG, Jinsheng LIN, Qiang ZHOU, Tong WU, Danfeng YE, Hong CAI, Wenquan ZHU, Wenbin CHEN, Min LI
  • Publication number: 20210269408
    Abstract: A method for synthesizing valsartan, comprising the steps of: synthesizing a valsartan methyl ester intermediate to obtain a reaction mixture of the valsartan methyl ester intermediate; diluting the reaction mixture by salt water or water, and then using a first extraction solvent to extract the valsartan methyl ester intermediate; adding alkali to an organic layer containing the valsartan methyl ester intermediate for hydrolyzing, removing the organic layer, regulating pH of a water layer to be acidic by using acid, using the first extraction solvent to extract, concentrating a part of solvent, or distilling the solvent to dryness, and then adding a new solvent; finally, crystallizing, filtering, and drying to obtain the valsartan.
    Type: Application
    Filed: July 17, 2018
    Publication date: September 2, 2021
    Inventors: Xiaohui ZHOU, Xiaoren ZHU, Yuanxun ZHU, Peng DONG, Peng WANG, Jinsheng LIN, Wenquan ZHU, Min LI
  • Publication number: 20200306245
    Abstract: Disclosed is N-formyl vortioxetine, and also disclosed is a method for preparing the N-formyl vortioxetine and a stable solid preparation of vortioxetine.
    Type: Application
    Filed: September 20, 2017
    Publication date: October 1, 2020
    Inventors: Jinsheng LIN, Tianpei HUANG, Feifei LAN, Xiaoyan XU, Libin HU, Dan LI, Wenquan ZHU, Min LI, Zhiyun WANG