- 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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Paragraph 0032; 0039; 0055; 0056
(2018/07/06)
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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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Paragraph 0023; 0024; 0028; 0033; 0034; 0035-0041
(2017/08/29)
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- 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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- 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
(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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- HMDS-promoted in situ amidation reactions of carboxylic acids and amines
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A number of N-acylalkylenediamines were synthesized in high yields by in situ monoamidation of carboxylic acids with diamines. The amidation reactions were carried out simply by heating the substrates at 110 °C for 5-24 h in the presence of HMDS.
- Chou, Wen-Chih,Chou, Ming-Chen,Lu, Yann-Yu,Chen, Shyh-Fong
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p. 3419 - 3422
(2007/10/03)
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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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