Patents by Inventor Ben Pan

Ben Pan 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: 11407730
    Abstract: The present invention relates to a method of preparing racemic nicotine comprising: (i) reacting ethyl nicotinate and N-vinylpyrrolidone in the presence of an alcoholate base to 3-nicotinoyl-1-vinylpyrrolidin-2-one; (ii) reacting the 3-nicotinoyl-1-vinylpyrrolidin-2-one with an acid to myosmine; (iii) reducing the myosmine to nornicotine using a reducing agent; and (iv) methylating the nornicotine to obtain the racemic nicotine.
    Type: Grant
    Filed: December 18, 2018
    Date of Patent: August 9, 2022
    Assignees: Siegfried AG, Contraf-Nicotex-Tobacco GmbH
    Inventors: Beat Theodor Weber, Christian Lothschütz, Ben Pan
  • Patent number: 11279685
    Abstract: The present invention relates to a method of separating racemic nicotine of Formula (1-a) as a mixture of the (R)- and (S)-enantiomers into the enantiomerically pure (S)- and (R)-nicotine represented by Formula (1-b) and (1-c), by adding a mixture of the L- and the D-enantiomer of a O,O?-disubstituted tartaric acid, wherein the molar ratio of the L- to the D-enantiomer is from 80:20 to 95:5, and obtaining the (S)-nicotine of formula (1-b), or by adding O,O?-dibenzoyl-D-tartaric acid and obtaining the (R)-nicotine of formula (1-c).
    Type: Grant
    Filed: December 18, 2018
    Date of Patent: March 22, 2022
    Assignees: SIEGFRIED AG, CONTRAF-NICOTEX-TOBACCO GMBH
    Inventors: Beat Theodor Weber, Ben Pan
  • Patent number: 11091458
    Abstract: The present invention relates to a method of preparing racemic nicotine comprising: (i) reacting ethyl nicotinate and N-vinylpyrrolidone in the presence of an alcoholate base to 3-nicotinoyl-1-vinylpyrrolidin-2-one; (ii) reacting the 3-nicotinoyl-1-vinylpyrrolidin-2-one with an acid to myosmine; (iii) reducing the myosmine to nornicotine using a reducing agent; and (iv) methylating the nornicotine to obtain the racemic nicotine.
    Type: Grant
    Filed: December 18, 2018
    Date of Patent: August 17, 2021
    Assignees: Siegfried AG, Contraf-Nicotex-Tobacco GmbH
    Inventors: Beat Theodor Weber, Christian Lothschütz, Ben Pan
  • Publication number: 20200331884
    Abstract: The present invention relates to a method of preparing racemic nicotine comprising: (i) reacting ethyl nicotinate and N-vinylpyrrolidone in the presence of an alcoholate base to 3-nicotinoyl-1-vinylpyrrolidin-2-one; (ii) reacting the 3-nicotinoyl-1-vinylpyrrolidin-2-one with an acid to myosmine; (iii) reducing the myosmine to nornicotine using a reducing agent; and (iv) methylating the nornicotine to obtain the racemic nicotine.
    Type: Application
    Filed: December 18, 2018
    Publication date: October 22, 2020
    Applicants: SIEGFRIED AG, CONTRAF-NICOTEX-TOBACCO GMBH
    Inventors: Beat Theodor Weber, Christian Lothschütz, Ben Pan
  • Publication number: 20200331883
    Abstract: The present invention relates to a method of separating racemic nicotine of Formula (1-a) as a mixture of the (R)- and (S)-enantiomers into the enantiomerically pure (S)- and (R)-nicotine represented by Formula (1-b) and (1-c), by adding a mixture of the L- and the D-enantiomer of a O,O?-disubstituted tartaric acid, wherein the molar ratio of the L- to the D-enantiomer is from 80:20 to 95:5, and obtaining the (S)-nicotine of formula (1-b), or by adding O,O?-dibenzoyl-D-tartaric acid and obtaining the (R)-nicotine of formula (1-c).
    Type: Application
    Filed: December 18, 2018
    Publication date: October 22, 2020
    Applicants: SIEGFRIED AG, CONTRAF-NICOTEX-TOBACCO GMBH
    Inventors: Beat Theodor WEBER, Ben PAN
  • Patent number: 10738058
    Abstract: The present invention discloses a method of manufacturing 4-chloro-7H-pyrrolo[2,3-d]pyrimidine comprising the steps: a) Preparing ethyl 2-cyano-4,4-dimethoxybutanoate by coupling ethyl 2-cyanoacetate and 2-bromo-1,1-dimethoxyethane; b) Preparing 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol by adding formamidine to ethyl 2-cyano-4,4-dimethoxybutanoate; c) Converting 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol to 7H-pyrrolo[2,3-d]pyrimidin-4-ol; and d) Converting the 7H-pyrrolo[2,3-d]pyrimidin-4-ol to 4-chloro-7H-pyrrolo[2,3-d]pyrimidine. The method offers increased yield, less by-products and a decrease in waste compared to methods known as being state of the art.
    Type: Grant
    Filed: August 11, 2017
    Date of Patent: August 11, 2020
    Assignee: Siegfried (Nantong) Pharmaceuticals Co. Ltd.
    Inventors: Ben Pan, Jiang Chen, Bernhard Berger, Beat Weber
  • Publication number: 20190169200
    Abstract: The present invention discloses a method of manufacturing 4-chloro-7H-pyrrolo[2,3-d]pyrimidine comprising the steps: a) Preparing ethyl 2-cyano-4,4-dimethoxybutanoate by coupling ethyl 2-cyanoacetate and 2-bromo-1,1-dimethoxyethane; b) Preparing 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol by adding formamidine to ethyl 2-cyano-4,4-dimethoxybutanoate; c) Converting 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol to 7H-pyrrolo[2,3-d]pyrimidin-4-ol; and d) Converting the 7H-pyrrolo[2,3-d]pyrimidin-4-ol to 4-chloro-7H-pyrrolo[2,3-d]pyrimidine. The method offers increased yield, less by-products and a decrease in waste compared to methods known as being state of the art.
    Type: Application
    Filed: August 11, 2017
    Publication date: June 6, 2019
    Applicant: Siegfried (Nantong) Pharmaceuticals Co. Ltd.
    Inventors: Ben Pan, Jiang Chen, Bernhard Berger, Beat Weber
  • Patent number: D1065727
    Type: Grant
    Filed: September 23, 2022
    Date of Patent: March 4, 2025
    Inventor: Ben Pan