Patents by Inventor Rapolu Raji Reddy

Rapolu Raji Reddy 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: 7737273
    Abstract: The present invention provides a novel process for the preparation of acyclic phosphonate nucleotide analogs using novel intermediates. Thus, for example, (R)-9-(2-phosphonomethoxypropyl)adenine is reacted with dimethylformamide dimethylacetal to give N4-dimethylaminomethyledino-9-(2-phosphonomethoxy ethyl) adenine, which is then reacted with chloromethyl-2-propyl carbonate in presence of triethylamine to give (R)-N4-Dimethylaminomethyledino-9-(2-phosphono methoxypropyl) adenine disoproxil, followed by deprotection with acetic acid to get tenofovir disoproxil. Tenofovir disoproxil is then treated with fumaric acid to give tenofovir disoproxil fumarate.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: June 15, 2010
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy
  • Patent number: 7732632
    Abstract: The present invention provides a process for obtaining highly pure crystalline form of oseltamivir free base, thus, for example, suspending or dissolving impure or non-crystalline oseltamivir free base in a hydrocarbon solvent and then isolating crystals to obtain oseltamivir free base in well defined crystalline form. The present invention also provides a process for preparation of oseltamivir phosphate in high purity.
    Type: Grant
    Filed: January 2, 2006
    Date of Patent: June 8, 2010
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy
  • Publication number: 20100137632
    Abstract: The present invention provides an improved and commercially viable process for the preparation of oseltamivir phosphate. Thus, for example, ethyl (3R,4R,5S)-4-amino-5-azido-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate is acetylated with acetic anhydride in methylene chloride in the presence of triethyl amine in the absence of water to give ethyl (3R,4R,5S)-4-(acetylamino)-5-azido-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate.
    Type: Application
    Filed: February 9, 2010
    Publication date: June 3, 2010
    Applicant: HETRO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy
  • Publication number: 20100137613
    Abstract: The present invention provides an improved and commercially viable process for preparation of eprosartan and its pharmaceutically acceptable acid addition salts thereof in high purity and in high yield. Thus, for example, methyl 4-[[2-butyl-5-formyl-1 H-imidazol-1-yl]methyl]benzoate is reacted with ethyl 2-carboxy-3-(2-thienyl)propionate in the presence of a base, such as piperidine or piperidinium propionate in propionic acid, in cyclohexane solvent to give ethyl (?E)-?-[(2-n-butyl-1-[(4-(methoxy-carbonyl) phenyl]methyl]-1 H-imidazol-5-yl]methylene-2-thiophene propionate substantially free of decarboxylate impurity namely, ethyl 3-(2-thienyl)propionate, which is then subjected to base hydrolysis followed by treatment with methanesulfonic acid to obtain eprosartan mesylate in high purity and in high yield.
    Type: Application
    Filed: December 27, 2006
    Publication date: June 3, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Medabalimi Peter Paul Raj
  • Publication number: 20100136116
    Abstract: The present invention provides a novel and stable hydrated form of erlotinib free base, and a process for its preparation thereof. The present invention also provides a process for preparation of erlotinib hydrochloride crystalline polymorph A substantially free of polymorph B. The present invention further relates to erlotinib hydrochloride crystalline particles having mean particle size (D50) ranging from about 4 ?m to 15 ?m and 90 volume-% of the particles (D90) ranging from about 14 ?m to 30 ?m, to the methods for the manufacture of said crystalline particles, and to pharmaceutical compositions comprising said crystalline particles.
    Type: Application
    Filed: August 17, 2007
    Publication date: June 3, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Thungathurthy Srinivasa Rao
  • Publication number: 20100130741
    Abstract: The present invention provides an improved and commercially viable process for preparation of erlotinib substantially free of N-methoxyethyl impurity, namely N-[(3-ethynylphenyl)-(2-methoxyethyl)]-6,7-bis(2-methoxyethoxy)-4-quinazolinamine, and its pharmaceutically acceptable acid addition salts thereof in High purity and in high yield. According to the present invention, erlotinib or a pharmaceutically acceptable acid addition salt of erlotinib substantially free of N-methoxyethyl impurity is prepared by isolating erlotinib or a pharmaceutically acceptable salt of erlotinib from a solvent medium comprising dimethyl sulfoxide and an alcoholic solvent.
    Type: Application
    Filed: July 11, 2007
    Publication date: May 27, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Thungathurthy Srinivasa Rao
  • Patent number: 7705142
    Abstract: There is provided an improved process for preparing cefixime. Thus, for example, 7-amino-3-vinyl-3-cephem-4-carboxylic acid is reacted with 2-mercapto-1,3-benzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-(methoxycarbonyl)-methoxyimino acetate in tetrahydrofuran and water at 4° C. in the presence of triethylamine. The reaction mass is extracted with ethyl acetate. 7-[2-(2-Amino-4-thiazolyl)-2-(methoxycarbonylmethoxyimino)acetamido]-3-vinyl-3-cephem-4-carboxylic acid triethylamine salt present in the aqueous layer is hydrolyzed with sodium hydroxide in less than 30 minutes and aqueous hydrochloric acid is added immediately to adjust the pH to 4.8 to 5.2. Then, aqueous hydrochloric acid is added at 35° C. to adjust the pH 2.5 and cooled to crystallize cefixime trihydrate in high purity.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: April 27, 2010
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Nagabelli Murali
  • Publication number: 20100093804
    Abstract: The present invention relates to a novel and stable crystalline polymorph of lansoprazole, a process for its preparation and to a pharmaceutical composition comprising it. Thus, for example, lansoprazole crude is dissolved in methanol at 20-30° C. followed by stirring and the solution is cooled to 0-10° C. The resulting solution is stirred for 1 hour to 1 hour 30 minutes at 0-10° C., the solid is filtered and then dried to give lansoprazole crystalline form III.
    Type: Application
    Filed: December 7, 2006
    Publication date: April 15, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy
  • Publication number: 20100087653
    Abstract: The invention provides a novel process for the preparation of lercanidipine or a pharmaceutical acceptable salt using novel intermediates. Thus, 2,N-dimethyl-N-(3,3-diphenylpropy1)-1-amino-2-propanol is reacted with trimethylsilyl chloride in presence of triethyl amine in methylene chloride to give 2,N-dimethyl-2-(trimethylsilyloxy)-N-(3,3-diphenylpropy1)-1-propanamine, which is then reacted with 2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carbonyl chloride for 2 hours and crystallized to obtain lercanidipine hydrochloride.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 8, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Dandamudi Satish Kumar
  • Patent number: 7687658
    Abstract: The present invention provides an improved and commercially viable process for the preparation of oseltamivir phosphate. Thus, for example, ethyl (3R,4R,5S)-4-amino-5-azido-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate is acetylated with acetic anhydride in methylene chloride in the presence of triethyl amine in the absence of water to give ethyl (3R,4R,5S)-4-(acetylamino)-5-azido-3-(1-ethylpropoxy)-1-cyclohexene-1-carboxylate.
    Type: Grant
    Filed: November 25, 2005
    Date of Patent: March 30, 2010
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy
  • Patent number: 7687653
    Abstract: The invention provides a novel process for the preparation of lercanidipine or a pharmaceutical acceptable salt using novel intermediates. Thus, 2,N-dimethyl-N-(3,3-diphenylpropyl)-1-amino-2-propanol is reacted with trimethylsilyl chloride in presence of triethyl amine in methylene chloride to give 2,N-dimethyl-2-(trimethylsilyloxy)-N-(3,3-diphenylpropyl)-1-propanamine, which is then reacted with 2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carbonyl chloride for 2 hours and crystallized to obtain lercanidipine hydrochloride.
    Type: Grant
    Filed: June 15, 2005
    Date of Patent: March 30, 2010
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Dandamudi Satish Kumar
  • Publication number: 20100076022
    Abstract: The present invention discloses novel and stable polymorphs of rimonabant, its hydrates and solvates, to the processes for their preparation and to pharmaceutical compositions comprising them. The present invention further discloses a novel and stable amorphous form of rimonabant, process for its preparation and a pharmaceutical composition comprising it. The present invention also provides an improved process for the preparation of rimonabant crystalline Form II. Thus, for example, rimonabant is dissolved in methylene dichloride, stirred for 10 minutes at 25-30° C. and then the solvent distilled off under vacuum at 40° C. The resulting residue is stirred with water and the separated solid is collected at 25-30° C. to give a stable crystalline rimonabant hydrate.
    Type: Application
    Filed: September 1, 2006
    Publication date: March 25, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy
  • Publication number: 20100076197
    Abstract: The present invention provides an improved and commercially viable process for the preparation of rimonabant substantially free of amide impurity, namely 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl-4-methyl-pyrazole-3-carboxamide and its pharmaceutically acceptable acid addition salts thereof. Thus, for example, 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl-4-methyl-pyrazole-3-carboxylic acid chloride is reacted with 1-aminopiperidine in the presence of a base and optionally a phase transfer catalyst is used such as tetra-butylammonium bromide in a biphasic reaction medium containing water and a water-immiscible solvent to obtain pure rimonabant.
    Type: Application
    Filed: September 11, 2006
    Publication date: March 25, 2010
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy
  • Patent number: 7638634
    Abstract: The present invention relates to a novel amorphous form of esomeprazole hydrate, to a process for its preparation and to a pharmaceutical composition containing it. Thus, tetrahydrofuran and water are added to esomeprazole potassium salt at 25-30° C., cooled to 20° C. and then the pH is adjusted to 7.5-8.0 with acetic acid. The reaction mass is cooled to 5° C., stirred for 2 to 3 hours at 0-5° C., filtered the mass, washed with chilled mixture of water and tetrahydrofuran (2:1) and again washed with water. The wet cake is dried at 30-35° C. under vacuum to reach the moisture content to 25-30%. The solid is again dried in rotovapour at 25-30° C. under nitrogen atmosphere to give amorphous esomeprazole hydrate.
    Type: Grant
    Filed: March 6, 2009
    Date of Patent: December 29, 2009
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy
  • Patent number: 7629482
    Abstract: The present invention relates to a process for preparing a key intermediate of cefprozil and use of this intermediate in the preparation of cefprozil thereby avoiding impurity-causing self-acylation. [R-(Z)]-[4-hydroxy-?-[(3-methoxy-1-methyl-3-oxo-1-propenyl)amino]] benzeneacetic acid, mono potassium salt is reacted with ethyl chloroformate to obtain mixed anhydride which is then silylated with N,O-bis(trimethylsilyl)acetamide. The silylated compound obtained is reacted with [7-trimethylsilylamino-3-(Z/E-propen-1-yl)-3-cephem-4-carboxylic acid]trimethylsilyl ester and deprotected with aqueous hydrochloric acid to give cefprozil.
    Type: Grant
    Filed: October 24, 2008
    Date of Patent: December 8, 2009
    Assignee: Hetero Drugs Limited
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Nagabelli Murali
  • Publication number: 20090275746
    Abstract: The present invention provides solid form of faropenem free acid, its hydrates and processes for their preparation thereof. Thus, for example, dissolving an alkali metal salt of faropenem in water, adjusting the pH of the solution formed with an acid to below about 2.5 and collecting the precipitated solid to obtain solid faropenem free acid.
    Type: Application
    Filed: July 28, 2006
    Publication date: November 5, 2009
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Dandamudi Satish Kumar
  • Publication number: 20090227800
    Abstract: The invention provides a novel process for the preparation of lercanidipine or a pharmaceutical acceptable salt using novel intermediates. Thus, 2,N-dimethyl-N-(3,3-diphenylpropyl)-1-amino-2-propanol is reacted with trimethylsilyl chloride in presence of triethyl amine in methylene chloride to give 2,N-dimethyl-2-(trimethylsilyloxy)-N-(3,3-diphenylpropyl)-1-propanamine, which is then reacted with 2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carbonyl chloride for 2 hours and crystallized to obtain lercanidipine hydrochloride.
    Type: Application
    Filed: June 15, 2005
    Publication date: September 10, 2009
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Dandamudi Satish Kumar
  • Publication number: 20090227645
    Abstract: The present invention relates to novel crystalline forms of valdecoxib, to processes for their preparation and to pharmaceutical compositions containing them.
    Type: Application
    Filed: March 13, 2009
    Publication date: September 10, 2009
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subadsh Chander Reddy
  • Publication number: 20090198066
    Abstract: The present invention relates to a novel amorphous form of esomeprazole hydrate, to a process for its preparation and to a pharmaceutical composition containing it. Thus, tetrahydrofuran and water are added to esomeprazole potassium salt at 25-30° C., cooled to 20° C. and then the pH is adjusted to 7.5-8.0 with acetic acid. The reaction mass is cooled to 5° C., stirred for 2 to 3 hours at 0-5° C., filtered the mass, washed with chilled mixture of water and tetrahydrofuran (2:1) and again washed with water. The wet cake is dried at 30-35° C. under vacuum to reach the moisture content to 25-30%. The solid is again dried in rotovapour at 25-30° C. under nitrogen atmosphere to give amorphous esomeprazole hydrate.
    Type: Application
    Filed: March 6, 2009
    Publication date: August 6, 2009
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi PARTHASARADHI REDDY, Kura RATHNAKAR REDDY, Rapolu RAJI REDDY, Dasari MURALIDHARA REDDY
  • Publication number: 20090197907
    Abstract: The present invention relates to a novel crystalline form of rupatadine free base, process for its preparation and to a pharmaceutical composition containing it. In accordance with the present invention rupatadine is suspended in n-hexane, n-heptane, cyclohexane, diethyl ether or diisopropyl ether, stirred for at least 1 hour, filtered the solid and dried to give crystalline rupatadine form-B. The isolation of novel rupatadine free base as crystalline form-B may be useful as a purification of rupatadine or a salt thereof.
    Type: Application
    Filed: April 1, 2005
    Publication date: August 6, 2009
    Applicant: HETERO DRUGS LIMITED
    Inventors: Bandi Parthasaradhi Reddy, Kura Rathnakar Reddy, Rapolu Raji Reddy, Dasari Muralidhara Reddy, Kesireddy Subash Chander Reddy