Patents by Inventor XINFA LI

XINFA LI 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).

  • Publication number: 20220112168
    Abstract: N-substituted formyl-alpha-substituted glycine ester is used as the initial raw material, a cyclization reaction is performed under the action of a dehydrating agent (trisubstituted phosphine dihalide, a combination of trisubstituted phosphine dihalide and an acyl halide reagent, or a combination of trisubstituted phosphine oxide and an acyl halide reagent) and an organic amine to obtain the substituted oxazole compound, and the resulting substituted oxazole compound can be further saponified and de-carboxylated to obtain a medical intermediate 4-substituent-5-substituent oxy-oxazole; the reaction process can be carried out in a continuous flow mode to improve the productivity and reduce operations; the byproduct trisubstituted phosphine oxide in the reaction process can be repeatedly used to reduce the cost; dehydrating agents (phosphorus oxychloride and phosphorus pentoxide).
    Type: Application
    Filed: December 8, 2021
    Publication date: April 14, 2022
    Inventors: Xinfa LI, Lishan ZHOU, Chengwei WANG, Ningning LIU, Yuxin QI
  • Patent number: 11208417
    Abstract: The present invention provides a simple process of preparing avibactam. Piperidine-5-one-2S-carboxylate II as the raw material is subjected to condensation reaction with O-protecting hydroxylamine hydrochloride; the resulting compound is subjected to reduction and chiral resolution to obtain 5R-substituted oxyaminopiperidine-2S-carboxylic acid V in a basic condition; then, the compound of formula V is subjected to urea cyclization, acyl chlorination, and amidation with phosgene, solid phosgene, or diphosgene in a “one-pot” process, and then subjected to deprotection, sulfation, and tetrabutylammonium salt formation reaction to obtain (2S,5R)-2-carbamoyl-7-oxo-1,6-diazabicyclo[3.2.1]octan-6-yl]oxy}sulfonyl tetra-n-butyl ammonium salt VII, and finally, the compound of formula VII is subjected to ion exchange to obtain avibactam I.
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: December 28, 2021
    Assignee: XINFA PHARMACEUTICAL CO., LTD
    Inventors: Yuxin Qi, Baolin Wang, Xin Xu, Lizhu Ju, Xinfa Li
  • Publication number: 20210332060
    Abstract: The present invention provides a simple process of preparing avibactam. Piperidine-5-one-2S-carboxylate II as the raw material is subjected to condensation reaction with O-protecting hydroxylamine hydrochloride; the resulting compound is subjected to reduction and chiral resolution to obtain 5R-substituted oxyaminopiperidine-2S-carboxylic acid V in a basic condition; then, the compound of formula V is subjected to urea cyclization, acyl chlorination, and amidation with phosgene, solid phosgene, or diphosgene in a “one-pot” process, and then subjected to deprotection, sulfation, and tetrabutylammonium salt formation reaction to obtain (2S,5R)-2-carbamoyl-7-oxo-1,6-diazabicyclo[3.2.1]octan-6-yl]oxy}sulfonyl tetra-n-butyl ammonium salt VII, and finally, the compound of formula VII is subjected to ion exchange to obtain avibactam I.
    Type: Application
    Filed: March 6, 2018
    Publication date: October 28, 2021
    Inventors: Yuxin QI, Baolin WANG, Xin XU, Lizhu JU, Xinfa LI
  • Publication number: 20210323920
    Abstract: The present application relates to methods of preparing 5R-[(benzyloxy) amino] piperidine-2S-carboxylic acid or its derivatives in an environment-friendly way. The method uses L-glutamic acid as a starting material, which is first subjected to esterification reaction in the presence of an acidic reagent, and then reacted successively with 2-haloacetate and N-protecting agent, or with N-protecting agent and 2-haloacetate under a basic condition to obtain compound IV; then, the obtained compound IV is subjected to intramolecular condensation into a ring under the action of a strong base to obtain N-protecting group piperidine-5-one-2S-carboxylate (V).
    Type: Application
    Filed: March 6, 2018
    Publication date: October 21, 2021
    Inventors: Yuxin QI, Xinfa LI, Xin XU, Baolin WANG, Hu QU, Shungen XIE
  • Patent number: 11142499
    Abstract: The present application relates to methods of preparing 5R-[(benzyloxy) amino] piperidine-2S-carboxylic acid or its derivatives in an environment-friendly way. The method uses L-glutamic acid as a starting material, which is first subjected to esterification reaction in the presence of an acidic reagent, and then reacted successively with 2-haloacetate and N-protecting agent, or with N-protecting agent and 2-haloacetate under a basic condition to obtain compound IV; then, the obtained compound IV is subjected to intramolecular condensation into a ring under the action of a strong base to obtain N-protecting group piperidine-5-one-2S-carboxylate (V).
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: October 12, 2021
    Assignee: XINFA PHARMACEUTICAL CO., LTD
    Inventors: Yuxin Qi, Xinfa Li, Xin Xu, Baolin Wang, Hu Qu, Shungen Xie
  • Patent number: 10662190
    Abstract: It relates to improved processes of preparing 5R-[(benzyloxy) amino] piperidine-2S-carboxylate and oxalate thereof. In the present invention, L-glutamic acid or L-glutamic acid sodium salt as the starting material is reacted with chloroactic acid under an alkaline condition via a substitution reaction to obtain compound III; then, compound III is reacted with alcohol in the presence of acid reagent via esterification reaction to obtain compound IV; under the action of strong base, compound IV is subjected to intramolecular condensation into ring, hydrolysis-decarboxylation, and esterification to obtain compound V; compound V is condensed with benzyloxy amine hydrochloride salt in the presence of alkaline to obtain compound VI; compound VI is subjected to reduction and chiral resolution to obtain 5R-[(benzyloxy) amino] piperidine-2S-carboxylate oxalate (IIb) which is then neutralized to obtain 5R-[(benzyloxy) amino] piperidine-2S-carboxylate (IIa).
    Type: Grant
    Filed: March 2, 2018
    Date of Patent: May 26, 2020
    Assignee: XINFA PHARMACEUTICAL CO., LTD
    Inventors: Baolin Wang, Yuxin Qi, Yinlong Zhao, Yuqi Teng, Jun Chen, Lizhu Ju, Xinfa Li
  • Patent number: 10570132
    Abstract: A method for preparing an intermediate for avibactam, and specifically relates to a method for preparing ({[(2S,5R)-2-carbamoyl-7-oxo-1,6-diazabicyclo[3.2.1]oct-6-yl]oxy}sulfonyl)tetrabutylammonium salt (II). With 5R-[(benzyloxy) amino] piperidine-2S-carboxylate oxalate (III) as the raw material is reacted with the amide of Formula IV via amidation to prepare the compound of Formula V; the resulting compound of Formula V is reacted with the carbonylation reagent via urea cyclization to obtain the compound of Formula VI; the benzyl or the substituted benzyl in the compound of Formula VI is removed by catalytic hydrogeneration, then the resulting compound is sulfatated by sulfur trioxide complex and is salinized into tetrabutylammonium to obtain the final product (II).
    Type: Grant
    Filed: March 6, 2018
    Date of Patent: February 25, 2020
    Assignee: XINFA PHARMACEUTICAL CO., LTD
    Inventors: Yuxin Qi, Xinfa Li, Baolin Wang, Hu Qu, Xin Xu, Lizhu Ju
  • Patent number: 10570133
    Abstract: A compound of Formula III as the raw material is hydrolyzed in an alkaline condition, then acidized to prepare a compound of Formula IV, and the resulting compound of formula IV and a solid phosgene or diphosgene are concurrently subjected to the urea cyclization and the chloroformylation reaction in the presence of an organic base and a catalyst to obtain a compound of formula V, and then the compound of formula V is amidated to obtain the final product (II). In the present invention, a “one-pot” method is adopted for urea cyclization, chloroformylation, and amidation reaction, and the intermediate products do not need post-treatments such as separation and purification.
    Type: Grant
    Filed: March 23, 2018
    Date of Patent: February 25, 2020
    Assignee: XINFA PHARMACEUTICAL CO., LTD
    Inventors: Yuxin Qi, Xinfa Li, Baolin Wang, Xin Xu, Yinlong Zhao, Yuqi Teng
  • Publication number: 20190263813
    Abstract: A compound of Formula III as the raw material is hydrolyzed in an alkaline condition, then acidized to prepare a compound of Formula IV, and the resulting compound of formula IV and a solid phosgene or diphosgene are concurrently subjected to the urea cyclization and the chloroformylation reaction in the presence of an organic base and a catalyst to obtain a compound of formula V, and then the compound of formula V is amidated to obtain the final product (II). In the present invention, a “one-pot” method is adopted for urea cyclization, chloroformylation, and amidation reaction, and the intermediate products do not need post-treatments such as separation and purification.
    Type: Application
    Filed: March 23, 2018
    Publication date: August 29, 2019
    Inventors: Yuxin QI, Xinfa LI, Baolin WANG, Xin XU, Yinlong ZHAO, Yuqi TENG
  • Publication number: 20190263812
    Abstract: A method for preparing an intermediate for avibactam, and specifically relates to a method for preparing ({[(2S,5R)-2-carbamoyl-7-oxo-1,6-diazabicyclo[3.2.1]oct-6-yl]oxy}sulfonyl)tetrabutylammonium salt (II). With 5R-[(benzyloxy) amino] piperidine-2S-carboxylate oxalate (III) as the raw material is reacted with the amide of Formula IV via amidation to prepare the compound of Formula V; the resulting compound of Formula V is reacted with the carbonylation reagent via urea cyclization to obtain the compound of Formula VI; the benzyl or the substituted benzyl in the compound of Formula VI is removed by catalytic hydrogeneration, then the resulting compound is sulfatated by sulfur trioxide complex and is salinized into tetrabutylammonium to obtain the final product (II).
    Type: Application
    Filed: March 6, 2018
    Publication date: August 29, 2019
    Inventors: Yuxin QI, Xinfa LI, Baolin WANG, Hu QU, Xin XU, Lizhu JU
  • Publication number: 20190256514
    Abstract: It relates to improved processes of preparing 5R-[(benzyloxy) amino] piperidine-2S-carboxylate and oxalate thereof. In the present invention, L-glutamic acid or L-glutamic acid sodium salt as the starting material is reacted with chloroactic acid under an alkaline condition via a substitution reaction to obtain compound III; then, compound III is reacted with alcohol in the presence of acid reagent via esterification reaction to obtain compound IV; under the action of strong base, compound IV is subjected to intramolecular condensation into ring, hydrolysis-decarboxylation, and esterification to obtain compound V; compound V is condensed with benzyloxy amine hydrochloride salt in the presence of alkaline to obtain compound VI; compound VI is subjected to reduction and chiral resolution to obtain 5R-[(benzyloxy) amino] piperidine-2S-carboxylate oxalate (IIb) which is then neutralized to obtain 5R-[(benzyloxy) amino] piperidine-2S-carboxylate (IIa).
    Type: Application
    Filed: March 2, 2018
    Publication date: August 22, 2019
    Inventors: Baolin WANG, Yuxin QI, Yinlong ZHAO, Yuqi TENG, Jun CHEN, Lizhu JU, Xinfa LI
  • Publication number: 20100313504
    Abstract: This invention discloses a wood board connection structure with heat transfer function which comprises flooring heat transfer and wood board blocks. A main reinforcement of each flooring heat transfer exposes out from the surface of a wood board block, at least one salient is formed on the side wall of the main reinforcement, a groove which is matched with the main reinforcement and the salient is formed on the corresponding wood board block, and the block of each flooring heat transfer is provided with a hollow part. The salient is a salient with a hook part. A cushion block can be added between each two flooring heat transfer to be used for ventilation, and the flooring heat transfer can also regulate indoor temperature; the wood board block can generate thermal expansion along with temperature variation, and a gap between each two wood board block units on the surface of the wood board block can be small and big along with the temperature variation.
    Type: Application
    Filed: September 3, 2009
    Publication date: December 16, 2010
    Inventor: XINFA LI