76801-93-9Relevant articles and documents
Contrast medium of the impurity F synthetic method and its impurity G contrast medium, impurity H and impurity M application in the synthesis of
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Paragraph 0032; 0037; 0038, (2019/07/05)
The invention relates to a synthesis method of contrast medium impurities, in particular to a contrast medium impurity F synthetic method and its in the contrast medium impurity G, impurity H and M application in the synthesis of the impurity, which belongs to the field of medical technology. The method is to 5 - nitro - 1, 3 - benzene dicarboxylic acid dimethyl ester (formula 2 compound) and 2, 3 - dihydroxy propylamine as raw materials of formula 3 compound, type 3 compound with hydrogen reduction reaction [...] 4 compound, of formula 4 with a compound obtained by reaction of the impurity F [...] contrast medium. The invention relates to 5 - nitro - 1, 3 - benzene dicarboxylic acid dimethyl ester (formula 2 compound) as the starting material, the synthesis of 5 - amino - N, double-N' - (2, 3 - dihydroxy-propyl) - diiodo - 1, 3 - benzene dicarboxylic amide (formula 1 compounds) and then to of formula 1 as the starting material for the synthesis of impurity G, impurity H and impurity M, for the contrast medium quality control to provide acceptable impurity reference substance.
IODINATION PROCESS FOR THE PREPARATION OF 3,5-DISUBSTITUTED-2,4,6-TRIIODO AROMATIC AMINES COMPOUNDS
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Page/Page column 20, (2013/05/22)
The invention discloses a improved process for the preparation of 3,5-disubstituted- 2,4,6-triiodo aromatic amines of formula (II), wherein R1 and R2 are defined as herein. The compounds of formula (II) are the key intermediates for the synthesis of a series of non-ionic contrast agents such as Iopamidol, Iohexol and Iodixanol. The process comprises reacting chlorine-free iodinating reagents with 3,5-disubstituted-2,4,6-triiodo aromatic amines to obtain 3,5-disubstituted-2,4,6-triiodo aromatic amines of formula (II), wherein the molar yield of the iodination reaction can reach to 89%.
Improvements in crystallization of 5-amino-N,N'-bis(2,3-dihydroxypropyl)-2,4,6,-triiodo-isophthalamide, an intermediate for synthesizing non-ionic X-ray contrast agents
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Page/Page column 4-5, (2011/02/26)
This invention relates to the crystallization process of 5-amino-N, N'- bis(2,3-dihydroxypropyl)-2,4,6-triiodo-1,3-benzenedicarboxamide ("Compound B"), an iodinated intermediate in the preparation of non-ionic X-ray contrast agents. The instant process utilizes a nanofiltration system to pass through low molecular weight salt, thereby reducing the solubility of Compound B in the retentate. This process increases supersaturation of the mother liquor and improves crystal growth in the crystallization following the initial one. The process of the present invention is useful in increasing the overall crystallization yield of Compound B in an industrial manufacturing process.