23680-84-4Relevant articles and documents
Zinc-mediated intramolecular acyl and imino transfer reactions of aryl iodides
Boulton, Lee T.,Fox, Martin E.,Hodgson, Paul B.,Lennon, Ian C.
, p. 983 - 986 (2005)
A method for the coupling of acyl and imino substituents to the sterically encumbered 5-position of a 4-aminoquinazoline was developed. Starting with a 4-amino-5-iodoquinazoline, the method employs a facile intramolecular zinc-mediated transfer from the 4-amino group to the iodo-bearing carbon. The method was found to be effective for a variety of substituents, in particular a pyridyl group required for the synthesis of Pfizer's prostate selective α1 antagonist candidate for the treatment of benign prostatic hyperplasia, UK-338,003.
Synthetic method for 2-chloro-4-amino-6,7-dimethoxy quinazoline
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Paragraph 0059; 0069; 0070; 0071; 0072; 0073; 0074-0077, (2017/10/05)
The invention discloses a synthetic method for 2-chloro-4-amino-6,7-dimethoxy quinazoline. The synthetic method comprises the following steps: 1) preparing 3,4-dimethoxyphenyl isocyanate; 2) preparing 3,4-dimethoxyphenyl cyanourea; 3) preparing a 2-chloro-4-amino-6,7-dimethoxy quinazoline crude product; and 4) preparing a 2-chloro-4-amino-6,7-dimethoxy quinazoline fine product. The synthetic method disclosed by the invention simplifies reaction steps and increases the product yield; reaction conditions are optimized, so that reactants react more sufficiently, and therefore, generation of byproducts is reduced, production efficiency is improved, reactants are prevented from being oxidized, reaction is more complete, the target object can be obtained by direct filtering and drying during post-treatment, and the yield is stable.
A NOVEL PROCESS FOR THE PREPARATION OF 2-HALO-4-AMINOQUINAZOLINES
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Page/Page column 8, (2008/12/07)
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.