26759-46-6, name is Methyl 2-amino-4,5-dimethoxybenzoate, belongs to esters-buliding-blocks compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. SDS of cas: 26759-46-6
Example 1: (Production of 6,7-dimethoxyquinazolin-4-one); Using acetic acid and an inorganic base, ammonia, as a catalyst, 6,7-dimethoxyquinazolin-4-one was produced in the manner mentioned below. 0.84 g (4 mmol) of methyl 4,5-dimethoxyanthranilate, 3.60 g (80 mmol) of formamide, 0.17 g (2.8 mmol) of acetic acid and 0.05 g (2.8 mmol) of ammonia from a pressure cylinder were put into an autoclave of SUS316 having a capacity of 25 mL and equipped with a stirrer, a thermometer and a pressure gauge in a nitrogen atmosphere, and reacted at 150C for 2 hours. After the reaction, the reaction liquid was cooled to room temperature, and the precipitated crystal was collected by filtration, washed with methanol and then dried in vacuum at 70C for 2 hours to obtain 0.77 g of a crystal. The obtained crystal was analyzed for the purity by high-performance liquid chromatography, and its purity was 99.5 %; and 6,7-dimethoxyquinazolin-4-one was obtained at a yield of 93.0 %. The result is shown in Table 1. Examples 2 to 4, and Comparative Examples 1 and 2: (Production of 6,7-dimethoxyquinazolin-4-one); The reaction and the post-treatment were carried out in the same manner as in Example 1, for which, however, the catalyst was changed as in Table 2. In Example 4, ammonium acetate was used as the catalyst; and in Comparative Examples 1 and 2, formic acid or potassium carbonate, respectively, was used alone as the catalyst like in JP-A 2002-338550 (Patent Reference 4). From the results in Table 1, it is known that the reaction system with acetic acid and a base coexisting therein of the present invention gives 6,7-dimethoxyquinazolin-4-one at a higher yield than the conventional reaction system with formic acid or potassium carbonate alone therein.
The synthetic route of 26759-46-6 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Mitsubishi Gas Chemical Company, Inc.; EP1997812; (2008); A1;,
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