- Chemoselective calcium-catalysed direct amidation of carboxylic esters
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Unactivated carboxylic esters and primary amines undergo calcium-catalysed direct amide bond formation in excellent yields under homogeneous conditions in toluene. This green and mild reaction proceeds chemoselectively with esters, whereas related carboxylic acids and amides remain unreactive.
- Nguyen, D. Thao,Lenstra, Danny C.,Mecinovi?, Jasmin
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p. 77658 - 77661
(2015/09/28)
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- PROCESS FOR THE PREPARATION OF ALFUZOSIN AND SALTS THEREOF
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The present invention relates to novel N-[3-[(4-acyl-/aroyl-substituted amino-6,7-dimethoxy-2-quinazolinyl)methylamino]propyl]tetrahydro-2-furancarboxamide derivatives, and a process for the preparation thereof. The novel compounds are useful for preparing alfuzosin or a pharmaceutically acceptable salt thereof in high yield and purity.
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Page/Page column 6-7
(2010/07/10)
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- METHOD OF PREPARING ANHYDROUS ALFUSOZIN HYDROCHLORIDE
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There is described a method of preparing anhydrous alfuzosin hydrochloride by means of a condensation reaction between N1-methyl-N2-(tetrahydrodrofuroyl-2)-propylenediamine and 4-amino-2-chloro-6,7-dimethoxyquinazoline. The obtained crude product is subsequently purified by further stages that include steps of preparing novel intermediates. The described alfuzosin synthesis and purification process allow to obtain this active ingredient with a high yield and purity, and therefore suitable to be employed as an active ingredient in medicaments.
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Page/Page column 14
(2010/04/03)
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- AN IMPROVED PROCESS FOR THE PREPARATION OF ALFUZOSIN AND ITS NOVEL POLYMORPH
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The present invention relates to an improved process for the preparation of Alfuzosin of formula (I). The process involves utilizing intermediate of formula (Ia) wherein S represents acid residue of organic acids like acetic acid, oxalic acid, succinic acid, methane sulfonic acid, p-toluene sulfonic acid and the like. The present invention also relates to novel Amorphous form of Alfuzosin of formula (I).
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Page/Page column 11
(2009/03/07)
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- A NOVEL PROCESS FOR THE PREPARATION OF 2-HALO-4-AMINOQUINAZOLINES
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2-Halo-4-aminoquinazolines are produced by a one-step process involving intramolecular cyclization of appropriately substituted formamide derivatives in the presence of phosphorous oxyhalides. Exemplary of the process is the intramolecular cyclization of 3,4-dimethoxy-6-cyanoaniline-1-yl formamide in the presence of phosphorous oxychloride to 2-chloro-4-amino-6,7-dimethoxyquinazoline. These chemical compounds are utilized as intermediates in the preparation of some of the important antihypertensive agents e.g. 2-chloro-4-amino-6,7-dimethoxyquinazolines is used for the synthesis of alfuzosin hydrochloride.
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Page/Page column 9
(2008/12/07)
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- PROCESS FOR PREPARING ALFUZOSIN
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Processes for preparing alfuzosin and pharmaceutically acceptable salts, solvates, hydrates thereof are disclosed. The present invention also discloses processes for preparation of anhydrous alfuzosin hydrochloride having substantially free from other pseudopolymorphic crystalline forms particularly dihydrate form of alfuzosin hydrochloride.
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Page/Page column 9-10
(2008/12/07)
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- AN IMPROVED PROCESS FOR THE PREPARATION OF ALFUZOSIN HYDROCHLORIDE
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The present invention relates to an improved process for the preparation of Alfuzosin hydrochloride of formula (I) by reacting N-(3-aminopropyl)-6,7-dimethoxy-N-methylquinazoline-2,4-diamine of Formula (II) with 1-(tetrahydrofuran-2-ylcarbonyl)-1H-imidazole of formula (IV) using acetonitrile as an organic solvent. This invention also relates to a method for the purification of N-(3-aminopropyl)-6,7-dimethoxy-N-methylquinazoline-2,4-diamine of formula (II), which is a key starting material of Alfuzosin hydrochloride by making its corresponding salt of formula (III) using an organic di-carboxylic acid in an alcoholic solvent wherein, A is denoted as a corresponding moiety of organic di-carboxylic acid.
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Page/Page column 7; 10-11
(2008/06/13)
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- PREPARATION OF ALFUZOSIN
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A process for preparing alfuzosin or a salt thereof, which minimizes the concentration of an N1-(4-amino-6,7-dimethoxyquinazolin-2-yl)-N1-methyl-N 2-(4-amino-6,7-dimethoxyquinazolin-2-yl)-propane-1,3-diamine impurity in the product.
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Page/Page column 6-7
(2008/06/13)
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- AN IMPROVED AND INDUSTRIAL PROCESS FOR THE PREPARATION OF ALFUZOSIN HYDROCHLORIDE AND ITS NOVEL POLYMORPHS
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An improved and industrial process for the preparation of Alfuzosin Hydrochloride and its novel polymorphs (Formula (I)).
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Page/Page column 11
(2008/06/13)
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- PROCESS FOR THE PREPARATION OF ALFUZOSIN
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The present invention relates to an improved process for the preparation of N-[3-[(4-amino-6,7-dimethoxy-2-quinazolinyl)methylamino]propyl]tetrahydrofuran-2-carboxamide of Formula (I).
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Page/Page column 9-10
(2008/06/13)
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- PROCESSES FOR THE PREPARATION OF ALFUZOSIN
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The invention relates to processes for the preparation of alfuzosin or pharmaceutically acceptable salts thereof in high purity. More particularly, it relates to the preparation of pure crystalline alfuzosin base. The invention also relates to pharmaceutical compositions that include the pure alfuzosin or a pharmaceutically acceptable salt thereof.
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Page/Page column 9
(2008/06/13)
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- PROCESS FOR THE PREPARATION OF ALFUZOSIN
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The present invention relates to a simple process for the preparation of alfuzosin, it's bases and its pharmaceutically acceptable salts thereof.
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Page/Page column 6-8
(2010/11/27)
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- CRYSTALLINE ALFUZOSIN BASE
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The present invention relates to crystalline alfuzosin base and processes for preparation of the said crystalline solid. Thus, for example, alfuzosin base (HPLC purity: 97%) is added to methanol and heated to reflux to form a clear solution, the solution is cooled to 25° - 30°C and stirred for 12 hours at the same temperature, the resulting solution is cooled to 10°- 15°C and stirred for 2 hours, and the resulting solid is filtered, washed with methanol and dried at 50°- 60°C for 4 hours to give 99.95% pure alfuzosin base.
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Page/Page column 5-6
(2010/10/20)
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- PROCESSES FOR THE PREPARATION OF ALFUZOSIN AND SALTS THEREOF AND NOVEL CRYSTALLINE FORMS OF ALFUZOSIN
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The present invention provides novel crystalline forms of a.lfuzosin and alfuzosin hydrochloride and processes for their preparation. Also provided are pharmaceutical compositions containing the new crystalline forms.
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Page/Page column 30
(2008/06/13)
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