Patents Assigned to Ranbaxy Laboratories Ltd.
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Patent number: 5869649Abstract: 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: GrantFiled: May 1, 1996Date of Patent: February 9, 1999Assignee: Ranbaxy Laboratories Ltd.Inventors: Jag Mohan Khanna, Vijay Kumar Handa, Ramesh Dandala, Ram Chander Aryan
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Patent number: 5792874Abstract: 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: GrantFiled: August 26, 1997Date of Patent: August 11, 1998Assignee: Ranbaxy Laboratories, Ltd.Inventors: Jag Mohan Khanna, Naresh Kumar, Chandrahas Khanduri, Mukesh Kumar Sharma, Pankaj Sharma, Swargam Sathyanarayan, Girij Pal Singh
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Patent number: 5763646Abstract: 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: GrantFiled: March 13, 1997Date of Patent: June 9, 1998Assignee: Ranbaxy Laboratories, Ltd.Inventors: Yatendra Kumar, Rajesh Kumar Thaper, Satyananda Misra, S. M. Dileep Kumar, Jag Mohan Khanna
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Patent number: 5763653Abstract: 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: GrantFiled: March 13, 1997Date of Patent: June 9, 1998Assignee: Ranbaxy Laboratories, Ltd.Inventors: Jag Mohan Khanna, Yatendra Kumar, Rajesh Kumar Thaper, Satyananda Misra, S. M. Dileep Kumar
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Patent number: 5756729Abstract: 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: GrantFiled: October 9, 1996Date of Patent: May 26, 1998Assignee: Ranbaxy Laboratories, Ltd.Inventors: Jag Mohan Khanna, Naresh Kumar, Chandrahas Khanduri, Mukesh Kumar Sharma, Pankaj Sharma, Swargam Sathyanarayan, Girij Pal Singh
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Patent number: 5728401Abstract: 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: GrantFiled: April 16, 1997Date of Patent: March 17, 1998Assignee: Ranbaxy Laboratories, Ltd.Inventors: Farhan Ahmed, Chetan Rajsharad, Himadri Sen
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Patent number: 5536830Abstract: 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: GrantFiled: May 30, 1995Date of Patent: July 16, 1996Assignee: Ranbaxy Laboratories, Ltd.Inventors: Jag M. Khanna, Yatendra Kumar, Rakesh K. Arora, Neera Tiwari, Shailendra K. Singh
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Patent number: 5410044Abstract: 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: GrantFiled: February 18, 1993Date of Patent: April 25, 1995Assignee: Ranbaxy Laboratories, Ltd.Inventors: Jag M. Khanna, Yatendra Kumar, Arun Malhotra, Rakesh Arora, Neera Tiwari
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Patent number: 5347000Abstract: 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: GrantFiled: April 21, 1993Date of Patent: September 13, 1994Assignee: Ranbaxy Laboratories Ltd.Inventors: Jag M. Khanna, Yatendra Kumar, Arun Malhotra