105355-26-8Relevant articles and documents
Preparation method of piogelimide
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Paragraph 0024; 0026; 0028; 0030-0031; 0033-0034; 0036, (2020/11/26)
The invention provides a preparation method of piogelimide, which comprises the following steps: by using 4-[2- (5-ethyl-2-pyridyl)ethyoxyl]nitrobenzene as a starting material, methanol as a solvent and Raney Ni as a catalyst, carrying out catalytic hydrogenation, carrying out pressure filtration on the reaction solution into hydrobromic acid to carry out acidification reaction, and adding cuprousoxide, methyl acrylate and acetone into the system; dropwise adding a sodium nitrite solution, drying the organic solvent by distillation under reduced pressure after the reaction is finished, addingammonia water, alkalifying the solution by using liquid caustic soda, and extracting the product by using ethyl acetate; and adding thiourea and sodium acetate into the ethyl acetate solution, performing heating reflux until the reaction is finished, cooling the reaction product, adding water, spin-drying the reaction product, and refining the product by using DMF to obtain a piogelimide finishedproduct. According to the method, the yield and purity of the product can be effectively improved, the raw material cost is greatly reduced, the production operation is simplified, the production efficiency is improved, and the influence on the environment is greatly reduced.
PROCESS FOR THE PREPARATION OF THIAZOLIDINE DERIVATIVES
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Page/Page column 16, (2008/12/06)
The present invention relates to an industrially advantageous process for the preparation of thiazolidine derivatives, such as pioglitazone of formula I and its pharmaceutically acceptable salts.This invention also provides novel synthetic intermediates useful in the process for the preparation of pioglitazone.
INTERMEDIATE COMPOUND WHICH IS USED FOR THE PREPARATION OF PIOGLITAZONE
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Example 2, (2008/06/13)
The present invention relates to a novel compound of formula (IV) which is an intermediate that can be used for the preparation of pioglitazone. It also relates to a method of obtaining the novel compound (IV) starting from the natural product L-tyrosine, in which the amino group is protected in the form of aromatic imino group, and a method of obtaining pioglitazone from the said intermediate.