Patents by Inventor Bohumil Proksa

Bohumil Proksa 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: 7619087
    Abstract: A method of preparation of Oxycodone of formula I by reacting thebaine of formula II, or its analogue of formula III, wherein R represents a C2 to C5 alkyl, an alkylaryl, preferably benzyl, methoxybenzyl, or allyl, with hydrogen peroxide or peroxoacids in the presence of oxalic acid in admixture with acetic or formic acid. From the resulting crystalline precipitate of 14-hydroxycodeinone oxalate, by addition of a base, 14-hydroxycodeinone of formula IV is released, which is hydrogenated with hydrogen in the presence of a catalyst to yield Oxycodone (I): Oxycodone is transformed to hydrochloride, which is used as the active ingredient in analgesic formulations.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: November 17, 2009
    Assignee: Zentiva, a.s.
    Inventors: Vladislav Snuparek, Lubica Ratkovska, Bohumil Proksa
  • Patent number: 7534895
    Abstract: The invention solves a new method of preparation of Carvedilol for pharmaceutical use. In the synthesis of Carvedilol a reaction of 4-(oxirane-2-ylmethoxy)-9H-arbazole (II) with 2-(2-methoxyphenoxy)ethylamine salts (IV) in the presence of a base, in an alcohol having the number of carbons C2 to C5 as a solvent, at an elevated temperature, is used. After processing of the crude reaction mixture crude Carvedilol is obtained, which is purified by crystallization from ethylacetate with an addition of activated carbon and the final substance is formulated by crystallization from ethylacetate.
    Type: Grant
    Filed: November 4, 2003
    Date of Patent: May 19, 2009
    Assignee: Zentiva, A.S.
    Inventors: Richard Hercek, Alojz Skoda, Bohumil Proksa
  • Publication number: 20070088162
    Abstract: A method of preparation of Oxycodone of formula I by reacting thebaine of formula II, or its analogue of formula III, wherein R represents a C2 to C5 alkyl, an alkylaryl, preferably benzyl, methoxybenzyl, or allyl, with hydrogen peroxide or peroxoacids in the presence of oxalic acid in admixture with acetic or formic acid. From the resulting crystalline precipitate of 14-hydroxycodeinone oxalate, by addition of a base, 14-hydroxycodeinone of formula IV is released, which is hydrogenated with hydrogen in the presence of a catalyst to yield Oxycodone (I): Oxycodone is transformed to hydrochloride, which is used as the active ingredient in analgesic formulations.
    Type: Application
    Filed: August 16, 2005
    Publication date: April 19, 2007
    Applicant: ZENTIVA, A.S.
    Inventors: Vladislav Snuparek, Lubica Ratkovska, Bohumil Proksa
  • Publication number: 20060167077
    Abstract: The invention solves a new method of preparation of Carvedilol for pharmaceutical use. In the synthesis of Carvedilol a reaction of 4-(oxirane-2-ylmethoxy)-9H-arbazole (II) with 2-(2-methoxyphenoxy)ethylamine salts (IV) in the presence of a base, in an alcohol having the number of carbons C2 to C5 as a solvent, at an elevated temperature, is used. After processing of the crude reaction mixture crude Carvedilol is obtained, which is purified by crystallization from ethylacetate with an addition of activated carbon and the final substance is formulated by crystallization from ethylacetate.
    Type: Application
    Filed: November 4, 2003
    Publication date: July 27, 2006
    Applicant: ZENTIVA, A.S.
    Inventors: Richard Hercek, Alojz Skoda, Bohumil Proksa