- NOVEL PROCESS TO PREPARE PIOGLITAZONE VIA SEVERAL NOVEL INTERMEDIATES
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A novel process for preparing thiazolidinediones, preferably Pioglitazone, as described. Also described are novel intermediates involved in its synthesis and process for their preparation and use in medicine.
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- An improved process for pioglitazone and its pharmaceutically acceptable salt
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An improved process for pioglitazone (1) is described. The process features high-yielding transformations employing inexpensive reagents and recoverable solvents.
- Madivada, Lokeswara Rao,Anumala, Raghupathi Reddy,Gilla, Goverdhan,Alla, Sampath,Charagondla, Kavitha,Kagga, Mukkanti,Bhattacharya, Apurba,Bandichhor, Rakeshwar
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experimental part
p. 1190 - 1194
(2010/04/22)
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- 5-(4-HYDROXYBENZYL)THIAZOLIDINE-2,4-DIONE AS INTERMEDIATE FOR SYNTHESIS OF THIAZOLIDINEDIONE BASED COMPOUNDS AND PROCESS FOR PREPARING THE SAME
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The present invention relates to 5-(4-hydroxybenzyl)thiazolidine-2,4-dione represented by the following Chemical Formula [1], which is useful as an intermediate for synthesis of thiazolidinedione based compounds, a method for preparing the compound, and a method for preparing pioglitazone or pioglitazone hydrochloride, which is a thiazolidinedione based drug and useful in treating and preventing diabetes, using the 5-(4-hydroxybenzyl)thiazolidine-2,4-dione represented by Chemical Formula [1] as an intermediate:
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Page/Page column 15; 22-23
(2009/12/28)
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- A PROCESS FOR THE PREPARATION OF 4-[2-(5-ETHYL-2-PYRIDYL)ETHOXY]NITROBENZENE AND PIOGLITAZONE
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A process for the preparation of 4-[2-(5-ethyl-2-pyridyi)ethoxy]nitrobenzene is described, which comprises the step of reacting 2-(5-ethyl-2-pyridyl)ethanol with 1-fluoro-4-nitrobenzene in acetone in the presence of an alkali metal hydroxide. The intermediate 4-[2-(5-ethyl-2-pyridyI)ethoxy]nitrobenzene is used for the preparation of pioglitazone.
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Page/Page column 8
(2009/12/05)
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- PROCESS FOR THE PREPARATION OF THIAZOLIDINE DERIVATIVES
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The present invention relates to an industrially advantageous process for the preparation of thiazolidine derivatives, such as pioglitazone of formula I and its pharmaceutically acceptable salts.This invention also provides novel synthetic intermediates useful in the process for the preparation of pioglitazone.
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Page/Page column 13; 18-19
(2008/12/06)
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- NOVEL PROCESS FOR THE SYNTHESIS OF PIOGLITAZONE AND ITS SALTS THEREOF
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Present invention relates to an improved process for the preparation of thiazolidinedione derivatives. Further the invention provides the hydrogenation of acid addition salt of benzylidene compound with less reducing agent under low Hydrogen gas pressure to get substantially pure thiazolidinedione derivatives with improved yields.
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Page/Page column 7
(2009/01/20)
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- AN IMPROVED PROCESS FOR THE PRODUCTION OF DERIVATIVES OF THIOZOLIDINEDIONES AND THEIR PRECURSORS
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The invention provides a process for preparing derivatives of thiozolidinediones and their precursors comprising, (a) reacting a compound of general formula I wherein R1, R2 and R3 may be same or different and represent H, alkyl or alkoxy with C varying from 1 to 6, halogens, mono or di-substituted alkyl and aryl amines, and M represents hydrogen (H) or alkali metal selected from Na, K or Li with a compound of formula II, wherein R4 has the same meaning as R1 or R2 or R3 and X is halogen in presence or absence of solvent(s) under effective conditions to produce nitro ethers of general formula III, where in R1 to R4 has the same meaning as given above, provided when M is H and not its alkali metal salt, an alkali metal salt such as hydroxide or carbonate is required to be added while conducting the said reaction, (b) subjecting the said nitro ethers, with or without isolation, to Raney nickel-catalyzed reduction under conditions effective to produce corresponding nitro aniline ethers (c) coupling the said aniline ether with acrylates under Meerwein arylation conditions in presence of hydrobromic acid to produce α bromo substituted carboxylic acid derivatives followed by subjecting to solvent extractive purification (d) cyclising the purified derivative of α bromo substituted carboxylic acid as obtained in step (c) with thiourea to yield 2-imino -4-thiazolidinones then (e) hydrolyzing the said 2-imino-4-thiazolidinones to produce 2, 4-thiazolidinones and converting the same to its hydrochloride salts as white crystalline solids known to exhibit antidiabetic activity, by conventional methods.
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Page/Page column 27; 28
(2010/10/20)
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- PROCESS FOR THE SYNTHESIS OF PIOGLITAZONE HYDROGEN CHLORIDE
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The invention relates to a process for the synthesis of pioglitazone hydrogen chloride - which is an antidiabetic drug - via novel intermediates by reacting 4-[2-(5-ethyl-2-pyridinyl)-ethoxy]-benzaldehyde salt of formula (II), wherein HX is: HCI, CF3COOH, C4H4O4, (COOH)2 with a base and then thiazolidine-2,4-dione, and the obtained 5-[[4-[2-(5-ethyl-2-pyridinyl)ethoxy]phenyl]methylene]-2,4-thiazolidinedione base is treated with hydrochloric acid and the obtained 5-[[4-[2-(5-ethyl-2-pyridinyl)ethoxy]phenyl] methylene]-2,4-tiazolidinedione hydrogen chloride of formula(III) is hydrogenated in the presence of a catalyst. Further objects of the invention are the salts of general formula (II) and the benzylidene derivative of formula (III).
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Page/Page column 12
(2008/06/13)
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- PROCESS FOR PREPARING THIAZOLIDINEDIONES
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This invention provides a process for reducing an exocyclic double bond at the 5-position of a thiazolidinedione moiety of a thiazolidinedione precursor comprising the steps of: a) preparing a solution or suspension of the thiazolidinedione precursor in a non-ether solvent medium with a base, and b) combining the solution or suspension with a dithionite source. Preferred solvent media include aqueous N,N-dimethylformamide. Sodium dithionite is a preferred dithionite source. In particular the application discloses preparation processes for Pioglitazone, Rosilitazone and Troglitazone.
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Page/Page column 12-13
(2008/06/13)
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- A PROCESS FOR PURIFICATION
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The present invention provides a process for purification of pharmaceutically active compounds selected from the group consisting of thiazolidinedione derivatives and trans-3-Ethyl-2,5-dihydro-4-methyl-N- [2-[4-[[[[(4-methylcyclohexyl)amino] carbonyl] amino]sulfonyl]phenyl]ethyl]-2-oxo-1H-pyrrole-1-carboxamide comprising extraction in a solvent comprising an alkanol (C1-C4) and ammonia.
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Page/Page column 12
(2010/02/12)
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- PROCESSES FOR MAKING THIAZOLIDINEDIONE DERIVATIVES AND COMPOUNDS THEREOF
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A compound of the formula (I): wherein A represents a ring group connected to the oxygen atom by a C1 to C6 hydrocarbon chain, R is hydrogen or a C1-C4 alkyl, and Q is hydrogen, or an amine protecting group such as acetyl, trifluoroacetyl, benzoyl, benzyl, or trityl, is useful in making thiazolidinedione derivatives (formula (II)), such as pioglitazone, rosiglitazone and troglitazone.
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- A NOVEL PROCESS TO PREPARE PIOGLITAZONE VIA SEVERAL NOVEL INTERMEDIATES.
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A novel process for preparing thiazolidinediones, preferably Pioglitazone, are described. Also described are novel intermediates involved in its synthesis and process for their preparation and use in medicine.
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- Pioglitazone hydrochloride
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Provided is a novel crystal form of pioglitazone hydrochloride and a method for making it. Also provided is a method for making a known crystal form of pioglitazone hydrochloride.
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- A PROCESS FOR THE PRODUCTION OF SUBSTITUTED PHENYL ETHERS
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The present invention provides a process to prepare substituted phenyl ethers. More particularly the present invention provides a process to produce a compound represented by the Formula I: wherein H1 is a substituted pyridyl group and R1 can be an aldehyde, cyano or nitro group.The compound I is a key intermediate in the preparation of pharmaceutically useful thiazolidinedione derivatives such as pioglitazone, rosiglitazone, etc.
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- Reduction method for substituted 5-methylene-thiazolidinediones
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The present invention provides a method for making known pharmaceutical compounds. More particularly the present invention provides a new reduction method for making thiazolidinedione derivatives, particularly ciglitazone, pioglitazone, and englitazone. This reduction method comprises reacting a compound of the formula II with a cobalt ion, a ligand and a reducing agent to achieve a compound of the formula I. STR1
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- Studies on antidiabetic agents. Synthesis and hypoglycemic activity of 5-[4-(pyridylalkoxy)benzyl]-2,4-thiazolidinediones
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The synthesis of a series of 5-[4-(pyridylalkoxy)benzyl]-2,4-thiazolidinediones is described. These compounds were evaluated for hypoglycemic and hypolipidemic activities in genetically obese and diabetic mice, yellow KK. 2-(2-Pyridyl)alkoxy derivatives were found to have much better hypoglycemic and hypolipidemic activities than 2-(3-pyridyl)- and 2-(4-pyridyl)alkoxy derivatives or even the previously reported compound, ciglitazone. The introduction of a hydroxyl group at the 2-position of the ethoxy chain potentiated the activities. Among the potent compounds, pioglitazone (AD-4833) was selected as a candidate compound.
- Sohda,Momose,Meguro,Kawamatsu,Sugiyama,Ikeda
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