Patents by Inventor Rajendra Narayanrao Kankan

Rajendra Narayanrao Kankan 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: 20100190797
    Abstract: Disclosed are processes for the preparation of crystalline polymorphic forms of zopiclone and their pharmaceutical compositions for use as a sedative.
    Type: Application
    Filed: December 10, 2008
    Publication date: July 29, 2010
    Applicant: CIPLA LTD.
    Inventors: Dharmaraj Ramchandra Rao, Rajendra Narayanrao Kankan, Maruti Ganpati Ghaghare, Sunilkumar Saroj
  • Publication number: 20100160643
    Abstract: A process for the preparation of trityl olmesartan comprising (a) condensing 4-(1-hydroxy-1-methylethyl)-2-propyl-imidazol-5-carboxylic acid alkyl ester with trityl biphenyl bromide in the presence of a polar aprotic solvent and a base selected from the group consisting of alkali metal carbonates, alkali metal hydroxides, alkali metal alkoxides, and tertiary amines to obtain a compound of formula V, b) deesterifying the compound of formula (V) with a base; and c) reacting the product of step (b) with 4-halomethyl-5-methyl-2-oxo-1,3-dioxolene of formula (IV), wherein X is halogen selected from F or Cl or Br or I, to obtain trityl olmesartan medoxomil of formula. The trityl olmesartan medoxomil may be deprotected to produce olmesartan medoxomil.
    Type: Application
    Filed: October 9, 2007
    Publication date: June 24, 2010
    Applicant: CIPLA LIMITED
    Inventors: Srinivas Laxminarayan Pathi, Revikumar Puppala, Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Publication number: 20100152229
    Abstract: A new polymorph of moxifloxacin hydrochloride is described, together with a method for making the polymorph.
    Type: Application
    Filed: November 13, 2007
    Publication date: June 17, 2010
    Applicant: CIPLA LIMITED
    Inventors: Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan, Srinivas Laxminarayan Pathi, Ravikumar Puppala, Manish Gangrade, Shashirekha Kanathala
  • Publication number: 20100137586
    Abstract: There is provided a compound of formula (III), and a process for preparing a compound of formula (V) comprising converting a compound of formula (III) to the compound (V), wherein (X) is fluoro, chloro, bromo or iodo. There is also provided a process for preparing a compound of formula (XI) comprising converting a compound of formula (X) to the compound (XI). The compounds (V) and (XI) so prepared may be used in a process for preparing gefitinib.
    Type: Application
    Filed: April 16, 2008
    Publication date: June 3, 2010
    Applicant: CIPLA LIMITED
    Inventors: Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan, Srinivas Laxminarayan Pathi
  • Publication number: 20100113804
    Abstract: There is provided a process for preparing dorzolamide and processes for preparing intermediates useful in the preparation of dorzolamide. In particular, there is provided a process for preparing an acetoamido sulfone of formula (viii) comprising oxidation of a hydroxysulfonamide of formula (vii) in the presence of an oxidizing agent selected from the group consisting of: a peracid, tert-butyl hydroperoxide, dimethyl dioxirane, selenium dioxide, m-phenanthroline di-N-oxide, nitric acid and hydrogen peroxide. There is also provided a process for preparing an acetoamidosulfone of formula (ix-a) comprising converting a hydroxy sulfone of formula (viii) to the acetoamidosulfone of formula (ix-a) in the presence of acetonitrile and an acid. There is also provided a process for separating the cis- and trans-isomers of dorzolamide from a mixture of the trans-isomer of dorzolamide and the cis-isomer of dorzolamide comprising reacting the mixture of isomers with a carboxylic acid.
    Type: Application
    Filed: May 7, 2008
    Publication date: May 6, 2010
    Applicant: CIPLA LIMITED
    Inventors: Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao, Shrikant Suresh Mudgal
  • Publication number: 20100113790
    Abstract: A process for preparing a compound of formula (III) comprising condensing an oxiranyl compound of formula (I) with an amine of formula (II) or a salt thereof wherein: R1 is a group selected from alkyl, aryl, allyl, alkoxy, cycloalkyl, heterocyclic, alkenyl, benzocycloalkyl, aralkyl, haloarylalkyl, heteroaralkyl, haloalkyl, alkoxyaralkyl, substituted silyl and benzyl; and R2 is hydrogen, optionally substituted silyl or optionally substituted benzyl. There is also described a process for preparing (R,R)-carmoterol from compound (III).
    Type: Application
    Filed: February 28, 2008
    Publication date: May 6, 2010
    Applicant: CIPLA LIMITED
    Inventors: Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao, Dilip Birari, Ashwini Amol Sawant
  • Publication number: 20100113526
    Abstract: A process for preparing Form A of (S)-5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl]sulfinyl]-1H-benzimidazole magnesium dihydrate, processes for preparing various intermediates useful in the preparation of Form A of (S)-5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl]sulfinyl]-1H-benzimidazole magnesium dihydrate and a novel polymorphic Form II of 5-methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)-methyl]thio]-1H-benzimidazole.
    Type: Application
    Filed: February 21, 2008
    Publication date: May 6, 2010
    Applicant: CIPLA LIMITED
    Inventors: Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan, Srinivas Laxminarayan Pathi, Gopalakrishna Sumana Bangalore
  • Patent number: 7705163
    Abstract: A process for the preparation of carvedilol of formula (I) (I) either in enantiomeric substantially pure form, or as an enantiomeric mixture, optionally as a pharmaceutically acceptable salt thereof, which process comprises reacting 2,3-eopxypropoxy carbazole of formula (II) (II) or the R or S enantiomer thereof, with N-[2-(2-methoxy-phenoxy)ethyl]-benzylamine of formula (V) (V) to yield benzyl carvedilol of formula (VI) (VI) which is debenzylated by catalytic hydrogenation to yield carvedilol of formula (I), either in enantiomeric substantially pure form, or as an enantiomeric mixture, and if desired reacting the thus formed carvedilol of formula (I) with an inorganic or organic acid to yield a pharmaceutically acceptable salt thereof, and/or, if desired, separating the enantiomers. The above process is characterised in that reaction of said 2,3-epoxypropoxy carbazole of formula (II) with said N-[2-(2-methoxy-phenoxy)ethyl]-benzylamine of formula (V) is carried out in water as the reaction medium.
    Type: Grant
    Filed: May 19, 2005
    Date of Patent: April 27, 2010
    Assignee: Cipla Limited
    Inventors: Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Publication number: 20100099887
    Abstract: A process for the preparation of anastrozole which comprises: a) brominating 3,5-bis(2-cyanoprop-2-yl)toluene (II) in an organic solvent using a brominating agent to obtain 3,5-bis(2-cyanoprop-2-yl)benzylbromide (III); b) heating the reaction mass of step a) to the reflux temperature of the organic solvent for a period of time no longer than 3 hours; c) isolating and purifying the bromo intermediate (III) using an organic solvent; d) alkylating the bromo intermediate in the presence of a base, optionally a phase transfer catalyst, a 1,2,4-triazole and an organic solvent to obtain anastrozole; and e) isolating and purifying the anastrozole from an organic solvent.
    Type: Application
    Filed: October 17, 2007
    Publication date: April 22, 2010
    Applicant: CIPLA LIMITED
    Inventors: Srinivas Laxminarayan Pathi, Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Publication number: 20100094004
    Abstract: A process for the preparation of a salt of N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine comprising reacting a 4˜halo-6,7-bis(2-methoxyethoxy) quinazoline with 3-aminophenyl acetylene or an acid salt thereof under acidic conditions to form the corresponding acid salt of N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine, the process optionally further comprising converting the acid salt of N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine to N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine.
    Type: Application
    Filed: April 3, 2008
    Publication date: April 15, 2010
    Applicant: CIPLA LIMITED
    Inventors: Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan
  • Publication number: 20100075999
    Abstract: The invention relates to a process for the preparation of anagrelide, and for the preparation of intermediates for use in preparing anagrelide. The invention also relates to the intermediates per se, in particular compounds of Formula (V): where R constitutes a suitable leaving group, which may not be hydrogen. The R group may be selected from: (i) —SiR13, (ii) —CH2Ar, (iii) —COOR2, and (iv) sulfonates such as —SO2R3.
    Type: Application
    Filed: February 6, 2008
    Publication date: March 25, 2010
    Applicant: CIPLA LIMITED
    Inventors: Srinivas Laxminarayan Pathi, Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Patent number: 7678916
    Abstract: The present invention relates to processes for the preparation of rosiglitazone, rosiglitazone prepared thereby and pharmaceutical compositions and therapeutic uses thereof, and methods of treatment employing the same.
    Type: Grant
    Filed: August 13, 2004
    Date of Patent: March 16, 2010
    Assignee: Cipla Limited
    Inventors: Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao, Manjinder Singh Phull, Dilip Ramda Birari
  • Patent number: 7666896
    Abstract: A process for preparing perindopril (III) or a pharmaceutically acceptable salt thereof, which process comprises a substituted benzyl ester of (2S,3aS,7aS)-octahydroindole-2-carboxylic acid (I) with N—[(S)-carbethoxybutyl]-(S)-alanine (II) where R represents a halo, C1-4 alkoxy or nitro substituent.
    Type: Grant
    Filed: April 7, 2005
    Date of Patent: February 23, 2010
    Assignee: Cipla Limited
    Inventors: Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Publication number: 20100016605
    Abstract: A one-pot process for the preparation of pantoprazole sodium by reacting 2-chloro methyl 3,4-dimethoxy pyridine hydrochloride with 2-mercapto-5-difluoromethoxy benzimidazole in an organic solvent system in presence of a phase transfer catalyst and further treating with aqueous sodium hypohalite solution comprising sodium hydroxide to obtain pantoprazole sodium in high yield and purity. The process for conversion of pantoprazole sodium to pantoprazole sodium sesquihydrate and also pantoprazole sodium monohydrate are also disclosed herein.
    Type: Application
    Filed: December 15, 2005
    Publication date: January 21, 2010
    Applicant: CIPLA LIMITED
    Inventors: Rajendra Narayanrao Kankan, Srinivas Laxminarayan Pathi
  • Patent number: 7645890
    Abstract: A process for preparing (+)duloxetine, or an acid addition salt thereof, which process comprises resolving racemic(±)duloxetine with a chiral acid so as to obtain a salt of the chiral acid and (+)duloxetine, substantially free of (?)duloxetine; and (ii) if desired, converting the salt prepared in step (i) to the free base or another acid addition salt as appropriate. The process for preparing (+)duloxetine, or an acid addition salt thereof, can further comprise an O-alkylation intermediate process step which is carried out in the presence of a base and a phase transfer catalyst.
    Type: Grant
    Filed: December 10, 2003
    Date of Patent: January 12, 2010
    Assignee: Cipla Limited
    Inventors: Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan
  • Publication number: 20090326028
    Abstract: A process for the preparation of compounds of formula IA, where R?CH3 (i.e. temozolomide): comprising diazotizing a compound of the formula IIA: where in R is as defined above in the presence of at least one metal halide, an acid and a source of nitrous acid, followed by conversion of acidic solution containing temozolomide. The conversion can be carried out by a liquid-liquid extraction technique in a water immiscible solvent. The temozolomide may be further purified in an acetone-water mixture.
    Type: Application
    Filed: September 28, 2007
    Publication date: December 31, 2009
    Applicant: CIPLA LIMITED
    Inventors: Srinivas Laxminarayan Pathi, Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan
  • Publication number: 20090325915
    Abstract: The invention provides three polymorphic forms of crystalline levosalbutamol sulphate designated herein as Forms I, II and III. Crystalline levosalbutamol sulphate Form I is characterised by a powder XRD pattern with peaks at 10.8, 11.9, 13.0, 18.3, 28.5±0.2 degrees 2 theta. Crystalline levosalbutamol sulphate Form II is characterised by a powder XRD pattern with peaks at 8.7, 9.6, 15.2, 15.7, 19.1, 27.2, 30.7±0.2 degrees 2 theta. Crystalline levosalbutamol sulphate Form III is characterised by a powder XRD pattern with peaks at 5.5, 6.9, 7.3, 18.7±0.2 degrees 2 theta. Processes for making the new polymorphic forms and pharmaceutical compositions comprising them are also provided.
    Type: Application
    Filed: July 14, 2009
    Publication date: December 31, 2009
    Inventors: Dharmaraj Ramchandra Rao, Rajendra Narayanrao Kankan, Alka Chaudhary
  • Patent number: 7638627
    Abstract: A process of preparing imatinib, either as the free base or as an acid addition salt, which process comprises reacting N-(2-methyl-5-aminophenyl-4-(3-pyridyl)-2-pyrimidine amine of formula (II) with a 4-(4-methyl-piperazino methyl)benzoyl halide of formula (III) in the presence of an inert organic solvent, so as to yield a hydrohalide salt of imatinib formula (I) where n represents 1, 2 or 3 and Hal represents bromo, chloro, fluoro or iodo, either in anhydrous or hydrated form, which can as desired optionally be further converted either to the free base or a further acid addition salt. The present invention is also concerned with imatinib prepared according to the above process.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: December 29, 2009
    Assignee: Cipla Limited
    Inventors: Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Patent number: 7638633
    Abstract: A process for preparation of rabeprazole sodium comprising oxidation of wet or dry rabeprazole sulphide with sodium hypohalite in water or a mixture of water and water miscible solvent using alkali metal hydroxide and catalyst is disclosed herein. The present invention also discloses process for preparation of rabeprazole sulphide.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: December 29, 2009
    Assignee: Cipla Limited
    Inventors: Srinivas Laxminarayan Pathi, Rajendra Narayanrao Kankan, Dharmaraj Ramachandra Rao
  • Publication number: 20090312357
    Abstract: Amorphous rifaximin, methods of making it, and pharmaceutical compositions containing it. Also described are methods of converting amorphous rifaximin to crystalline rifaximin and vice versa.
    Type: Application
    Filed: September 24, 2007
    Publication date: December 17, 2009
    Applicant: CIPLA Limited
    Inventors: Dharmaraj Ramachandra Rao, Rajendra Narayanrao Kankan, Manjinder Singh Phull, Maruti Ghagare