19745-07-4Relevant articles and documents
Favipiravir intermediate and synthesis method of favipiravir
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Paragraph 0067-0069, (2020/08/12)
The invention discloses a favipiravir intermediate and a synthesis method of favipiravir. The synthesis method comprises the following steps: taking 2,5-dihalopyrazine as an initial raw material, reacting 2,5-dihalopyrazine with formamide under the action of an oxide and a catalyst to generate 6-halo-3-chloro-2-amide pyrazine; carrying out a reaction on 6-halo-3-chloro-2-amide pyrazine under the action of a dehydration chlorinating agent and an acid-binding agent to generate a favipiravir intermediate 3,6-dichloro-3-cyanopyrazine; carrying out an aromatic ring fluorination reaction on the obtained favipiravir intermediate and potassium fluoride in dimethyl sulfoxide to generate 3,6-difluoro-3-cyanopyrazine; adding the 3,6-difluoro-3-cyanopyrazine into a water solution containing sodium acetate, and carrying out hydrolysis to obtain 6-fluoro-3-hydroxyl-2-cyanopyrazine; and finally, carrying out a cyano hydrolysis reaction to obtain favipiravir. A mixture of 2,5-dichloropyrazine and 2-chloro-5-bromopyrazine are used as raw materials to synthesize the favipiravir intermediate, the raw material cost is remarkably reduced, and the provided synthesis method has the technical advantages of high yield and low cost.
BIPIPERIDINYL COMPOUNDS, COMPOSITIONS CONTAINING SUCH COMPOUNDS AND METHODS OF TREATMENT
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Page/Page column 53-54, (2008/12/07)
Bipiperidinyl compounds of the formula I, are disclosed as useful for treating or preventing type 2 diabetes and similar conditions. Pharmaceutically acceptable salts and solvates are included as well. The compounds are useful as agonists of the g-protein coupled receptor GPR-119.
AMIDOPYRAZOLE DERIVATIVE
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Page/Page column 28-29, (2010/11/23)
A platelet coagulation inhibitor which inhibits neither COX-1 nor COX-2 is provided. The inhibitor is a compound represented by general formula (I): wherein Ar1 and Ar2 independently represent a 5- or 6-membered aromatic heterocyclic group optionally substituted with 1 to 3 substituents, or a phenyl group optionally substituted with 1 to 3 substituents; R1 represents a lower acyl group, carboxyl group, a lower alkoxycarbonyl group, a lower alkoxy group, a lower alkyl group optionally substituted with 1 or 2 substituents, a carbamoyl group optionally substituted with 1 or 2 substituents, an oxamoyl group optionally substituted with 1 or 2 substituents, an amino group optionally substituted with 1 or 2 substituents, a 4- to 7-membered alicyclic heterocyclic group optionally substituted with 1 or 2 substituents, a phenyl group optionally substituted with 1 to 3 substituents, or a 5- or 6-membered aromatic heterocyclic group optionally substituted with 1 to 3 substituents; and R2 represents hydrogen atom, a halogeno group, or the like.