Patents Assigned to Ranbaxy Laboratories Ltd.
  • Patent number: 5869649
    Abstract: A process for preparing certain cephalosporin antibiotics, namely, cefotaxime, cefetemet, and ceftriaxone sodium comprising acylation of 7-amino-3-cephem-4-carboxylic acid derivatives with 2-mercapto-5-methyl-1,3,4-thiadiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-metho xyiminoacetate having the formula: ##STR1##
    Type: Grant
    Filed: May 1, 1996
    Date of Patent: February 9, 1999
    Assignee: Ranbaxy Laboratories Ltd.
    Inventors: Jag Mohan Khanna, Vijay Kumar Handa, Ramesh Dandala, Ram Chander Aryan
  • Patent number: 5792874
    Abstract: A multistep process for producing 8-chloro-6-(2-fluorophenyl)-1-methyl-4-H-imidazo?1,5a!?1,4!benzodiazepine (midazolam) comprises treating a compound of Formula II with a lower alkyl dithiol to produce a compound of Formula III, wherein n=2 or 3, converting the compound of Formula III to a compound of Formula VII, and then treating the compound of Formula VII with a deprotecting agent, thereby producing midazolam. Novel intermediate compounds are also disclosed.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: August 11, 1998
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Jag Mohan Khanna, Naresh Kumar, Chandrahas Khanduri, Mukesh Kumar Sharma, Pankaj Sharma, Swargam Sathyanarayan, Girij Pal Singh
  • Patent number: 5763646
    Abstract: A process for preparing simvastatin from lovastatin or mevinolinic acid in salt form comprises treating either starting material with cyclopropyl or butyl amine, the pyranone ring thereby being opened when lovastatin is the starting material, adding a methyl group to the 2-methylbutyrate side chain, and thereafter closing the open pyranone ring to produce simvastatin. The process is performed without protecting and deprotecting the two hydroxy groups of the open pyranone ring. In a preferred embodiment, the starting material is treated with cyclopropyl amine which produces simvastatin via the novel intermediate lovastatin cyclopropyl amide.
    Type: Grant
    Filed: March 13, 1997
    Date of Patent: June 9, 1998
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Yatendra Kumar, Rajesh Kumar Thaper, Satyananda Misra, S. M. Dileep Kumar, Jag Mohan Khanna
  • Patent number: 5763653
    Abstract: A process for preparing simvastatin from lovastatin or mevinolinic acid in salt form comprises treating either starting material with cyclopropyl or butyl amine, the pyranone ring thereby being opened when lovastatin is the starting material, adding a methyl group to the 2-methylbutyrate side chain, and thereafter closing the open pyranone ring to produce simvastatin. The process is performed without protecting and deprotecting the two hydroxy groups of the open pyranone ring. In a preferred embodiment, the starting material is treated with cyclopropyl amine which produces simvastatin via the novel intermediate lovastatin cyclopropyl amide.
    Type: Grant
    Filed: March 13, 1997
    Date of Patent: June 9, 1998
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Jag Mohan Khanna, Yatendra Kumar, Rajesh Kumar Thaper, Satyananda Misra, S. M. Dileep Kumar
  • Patent number: 5756729
    Abstract: A multistep process for producing 8-chloro-6-(2-fluorophenyl)-1-methyl-4-H-imidazo?1,5a!?1,4! benzodiazepine (midazolam) comprises treating a compound of Formula II with a lower alkyl dithiol to produce a compound of Formula III, wherein n=2 or 3, converting the compound of Formula III to a compound of Formula VII, and then treating the compound of Formula VII with a deprotecting agent, thereby producing midazolam. Novel intermediate compounds are also disclosed.
    Type: Grant
    Filed: October 9, 1996
    Date of Patent: May 26, 1998
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Jag Mohan Khanna, Naresh Kumar, Chandrahas Khanduri, Mukesh Kumar Sharma, Pankaj Sharma, Swargam Sathyanarayan, Girij Pal Singh
  • Patent number: 5728401
    Abstract: An effervescent pharmaceutical composition for oral use in the treatment of a condition mediated through histamine H.sub.2 receptors contains a therapeutically effective amount of ranitidine or a physiologically acceptable salt thereof, about 25-70% by weight of disodium citrate, and about 20-50% by weight of sodium bicarbonate. Optionally, the effervescent composition may also Include about 0.5-25% by weight of an edible organic acid such as fumaric acid. Preferably, the effervescent composition is in the form of a tablet. Additional excipients for the effervescent composition include about 2-10% by weight of glycine, a flavoring agent, a sweetening agent, a binding agent, and/or a lubricant.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: March 17, 1998
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Farhan Ahmed, Chetan Rajsharad, Himadri Sen
  • Patent number: 5536830
    Abstract: A process for converting cephalosporin p-nitrobenzyl ester (Formula I) to the corresponding cephalosporin free acid (Formula II) comprising treating the cephalosporin p-nitrobenzyl ester with a metal selected from the group consisting of iron, magnesium, aluminum, and tin, and with hydrochloric acid in a mixture of water and a water-miscible organic solvent. Preferably, the metal is iron in the form of a fine powder, and the reaction is carried out at a temperature in the range of 30.degree.-50.degree. C.
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: July 16, 1996
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Jag M. Khanna, Yatendra Kumar, Rakesh K. Arora, Neera Tiwari, Shailendra K. Singh
  • Patent number: 5410044
    Abstract: A process for the manufacture of 7-acylamino-3-hydroxycephem-4-carboxylate-1-oxide in E-rotamer form (Formula III), comprises reacting a 7-acylamino-3-exomethylenecepham-4-carboxylate-1-oxide with ozone in an inert organic solvent in the presence of a catalytic amount of an organic or inorganic base at a temperature ranging from about -80.degree. C. to about +20.degree. C. The E-rotamer (wherein the 3-hydroxy group is strongly hydrogen bonded to the carbonyl of the 4-ester group) exhibits different chemical and physical properties from and is more thermodynamically stable than, the Z-rotamer (wherein there is no hydrogen bonding between the 3-hydroxy group and the carbonyl of the 4-ester group).
    Type: Grant
    Filed: February 18, 1993
    Date of Patent: April 25, 1995
    Assignee: Ranbaxy Laboratories, Ltd.
    Inventors: Jag M. Khanna, Yatendra Kumar, Arun Malhotra, Rakesh Arora, Neera Tiwari
  • Patent number: 5347000
    Abstract: A process for preparing a 2-chlorosulfinylazetidinone comprises heating in an inert organic solvent a penicillin sulfoxide ester, at a temperature between about 75.degree. C. and 140.degree. C., with an N-chlorohalogenating agent in the presence of a weakly basic N-alkali metal salt of a cyclic imide. The weakly basic N-alkali metal salt of a cyclic imide acts as an acid scavenger to bind the hydrogen chloride which is produced as a byproduct of the reaction. Preferably, the N-chlorohalogenating agent is N-chlorosuccinimide or N-chlorophthalimide, and the weakly basic N-alkali metal salt of a cyclic imide is the sodium or potassium salt of succinimide or phthalimide.
    Type: Grant
    Filed: April 21, 1993
    Date of Patent: September 13, 1994
    Assignee: Ranbaxy Laboratories Ltd.
    Inventors: Jag M. Khanna, Yatendra Kumar, Arun Malhotra