- Improved method used for preparing quinazoline drugs
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The invention relates to an improved method used for preparing quinazoline drugs, and provides a synthesis route taking 2-chloro-4-amino-6,7-dimethoxyquinazoline as an intermediate. The synthesis route comprises following steps: acrylonitrile and a methylamine alcohol solution are subjected to amination reaction so as to obtain intermediate (I); triethylamine is taken as an acid binding agent, andbenzyl chloride is taken as a protective group so as to obtain an intermediate (II); a metal hydride is adopted so as to obtain an intermediate (III) through reduction; acylation with tetrahydro-2-furancarbonylchloride is carried out so as to obtain an intermediate (IV); the intermediate (IV) and ammonium formate are subjected to hydrogenolysis under catalytic effect of palladium on carbon so asto obtain an intermediate (V); and at least condensation reaction with 2-chloro-4-amino-6,7-dimethoxyquinazoline is carried out so as to obtain quinazoline drug Alfuzosin Hydrochloride (VI). Comparedwith the prior art, the improved method possesses following advantages: operation is simple and safe; reaction conditions are convenient to control; energy consumption is low; yield is stable; and industrialized application prospect is promising.
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- A process for the preparation of alfuzosin hydrochloride method (by machine translation)
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The invention relates to a process for the preparation of alfuzosin hydrochloride method, method comprises the following steps: (1) 15 °C following, acrylonitrile into the the methylamine is mellow solution to stir, by distillation to obtain (I); (2) to (I) is dripped reducing agent in an organic solvent, heating to reflux, then slowly sequentially into the 25% sodium hydroxide solution and distilled water, by the distillation treatment to obtain the (II); (3) under dry condition, the thionyl chloride is slowly dripped into the 2 - tetrahydrofuran formic acid, a 2 - tetrahydrofuran chloride; (4) the temperature control in the 5 - 15 °C conditions, will be 2 - tetrahydrofuran formyl the chlorine drips into containing acid, organic solvent and (II) of the mixed solution, then completing the stirring 3 hours, for 25% sodium hydroxide solution to neutralize, by organic solvent extraction, (III) be; (5) to (III) with 2 - chloro - 4 - amino - 6, 7 - dimethoxy quinazoline in presence of organic solvent, reflux stirring 4 - 10 hours, cooling and filtering, and steaming and removing the organic solvent, acetone dispersed precipitate solid, then re-crystallizing mixed solvent, to get the alfuzosin hydrochloride (IV). (by machine translation)
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- Process for the Preparation of Alfuzosin Hydrochloride
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A process for preparing alfuzosin or a salt thereof comprising: (a) condensing 4-amino-2-chloro-6,7-dimethoxyquinazoline with 3-methylaminopropionitrile in the presence of a polar aprotic solvent selected from the group consisting of diglyme, dimethyl formamide, t-butanol, hexamethylphosphoramide or mixtures thereof to form N-(4-amino-6,7-dimethoxyquinazol-2-yl)-N-methyl-2-cyanoethylamine (b) hydrogenating the N-(4-amino-6,7-dimethoxyquinazol-2-yl)-N-methyl-2-cyanoethylamine using a hydrogenating agent under a pressure of less than 10 kg/cm2 to form N-(4-amino-6,7-dimethoxyquinazol-2-yl)-N-methylpropylenediamine and optionally converting the N-(4-amino-6,7-dimethoxyquinazol-2-yl)-N-methylpropylenediamine to an acid addition salt thereof; and (c) converting tetrahydrofuroic acid to an intermediate form and condensing the intermediate form with the N-(4-amino-6,7-dimethoxyquinazol-2-yl)-N-methylpropylenediamine or with the acid addition salt to yield alfuzosin base, and optionally converting alfuzosin base to a salt of alfuzosin.
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Page/Page column 8
(2010/10/19)
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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 13; 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 10
(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 9-10
(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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- 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) comprising a step of reacting compound of formula (IV) with compound of formula (V) in presence of aprotic solvent to obtain compound of formula (III) which is a useful intermediate for synthesis of Alfuzosin hydrochloride of formula (I).
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Page/Page column 8
(2009/03/07)
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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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- 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 7
(2008/06/13)
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- ALFUZOSIN HYDROCHLORIDE POLYMORPHS
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Alfuzosin hydrochloride crystalline and amorphous polymorphic forms and processes for preparing them.
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Page/Page column 5
(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 13
(2008/06/13)
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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 31-32
(2008/06/13)
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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 6
(2010/10/20)
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- Synthesis and antihypertensive activity of a series of 4-amino-6,7-dimethoxyquinazoline derivatives
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A series of N2-[(acylamino)alkyl]-6,7-dimethoxy-2,4-quinazolinediamines was synthesized as potential α1-adrenoceptor antagonists. When administered to spontaneously hypertensive rats at 10 mg/kg po, a number of propanediamine derivatives showed good antihypertensive activity, whereas the ethanediamine derivatives, albeit being structurally more closely related to prazosin, were devoid of this property. The most active derivative, N-[3-[(4-amino-6,7-dimethoxy-2-quinazolinyl)methylamino]propyl]tetrahydro- 2-furancarboxamide hydrochloride, alfuzosin, showed high selectivity for peripheral α1-postjunctional adrenoceptors. At equiactive antihypertensive doses, its effect on the pressor response to postural changes in conscious dog was less marked than that shown by prazosin. In the light of these results, alfuzosin was selected for clinical evaluation.
- Manoury,Binet,Dumas,Lefevre-Borg,Cavero
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