356783-29-4

Basic information

• Product Name: Pyrazinecarboxamide, 3,6-difluoro- (9CI)
• Synonyms: Pyrazinecarboxamide, 3,6-difluoro- (9CI);3,6-difluoropyrazine-2-carboxaMide
• CAS NO: 356783-29-4
• Molecular Formula: C₅H₃F₂N₃O
• Molecular Weight: 159.0936264
• Product Categories: AMIDE;HALIDE
• Mol File: 356783-29-4.mol
• Article Data: 9

Chemical Properties

• Appearance: /
• Storage Temp.: under inert gas (nitrogen or Argon) at 2-8°C
• CAS DataBase Reference: Pyrazinecarboxamide, 3,6-difluoro- (9CI)(CAS DataBase Reference)
• NIST Chemistry Reference: Pyrazinecarboxamide, 3,6-difluoro- (9CI)(356783-29-4)
• EPA Substance Registry System: Pyrazinecarboxamide, 3,6-difluoro- (9CI)(356783-29-4)

Safety Data

• Hazardous Substances Data: 356783-29-4(Hazardous Substances Data)

Usage

Uses

Des-(3-Oxo-3,4-dihydrogen) 3,6-Difluoro Favipiravir is a building block related to Favipiravir(F103350). Favipiravir is used for the treatment of advanced Ebola virus infection in a small animal model. Favipiravir suppressed the replication of Zaire Ebola virus and prevented a lethal outcome in 100% of the animals. Based on the studies, Favipiravir can be a candidate for the treatment of Ebola hemorrhagic fever.

Upstream product

• 5424-01-1 3-aminopyrazinoic acid 
• 16298-03-6 Methyl 3-amino-2-pyrazinecarboxylate 
• 6966-01-4 methyl 3-amino-6-bromopyrazine-2-carboxylate 
• 21874-61-3 3-hydroxy-6-bromopyrazine-2-carboxylic acid methyl ester 
• 356783-26-1 methyl 3,6-difluoropyrazine-2-carboxylate 
• 17231-50-4 6-chloro-3-aminopyrazine-2-carbonitrile 
• 1301613-77-3 3,6-dibromo-2-pyrazinamide 
• 356783-16-9 3,6-dichloropyrazine-2-carbonitrile 
• 18960-19-5 1,4-dioxopyrazinamide 
• 19847-12-2 2-pyrazine carbonitrile 
• 356783-28-3 3,6-difluoropyrazine-2-carbonitrile 

Downstream Products

• 259793-96-9 favipiravir 

Relevant articles and documents

METHODS FOR PREPARING FAVIPIRAVIR

The present invention provides methods for preparing Favipiravir (6-fluoro-3-hydroxypyrazine-2-carboxamide).

Fapiravir and preparation method of intermediate thereof

The invention relates to a fapiravir and a preparation method of an intermediate thereof, and belongs to the field of pharmaceutical chemicals. The invention provides a preparation method of a fapiravir intermediate 3-hydroxy sodium pyrazine-2-formamide, wherein the fapiravir intermediate 3-hydroxy sodium pyrazine-2-formamide is prepared by reacting aminopropanedioide with lithium chloride in thepresence of a NaOH solution and glyoxal. The invention also provides a preparation method of 6-bromo-3-hydroxy pyrazine-2-formamide, wherein the 6-bromo-3-hydroxy pyrazine-2-formamide is prepared froman acetonitrile solution of 3-hydroxy sodium pyrazine-2-formamide and an acetonitrile solution of liquid bromine in a microchannel reactor. The invention also provides a preparation method of 3, 6-difluoropyrazine-2-formamide, wherein the 3, 6-difluoropyrazine-2-formamide is prepared by reacting 6-bromo-3-hydroxy pyrazine-2-formamide with potassium bifluoride in the presence of PEG-400 and DMF. Finally, the invention also provides a total synthesis method for preparing fapiravir from the intermediate. The reactions avoid the use of highly dangerous diazotization reactions, and the methods have the advantages of high safety, low raw material price, short steps, low cost and simple post-treatment, and are suitable for industrial enlarged production.

Favipiravir intermediate and synthetic method for favipiravir

The invention relates to a favipiravir intermediate and a synthetic method for favipiravir, and specifically discloses a method for synthesizing 3,6-difluoro-2-cyanopyrazine with a formula 4 as shownin the specification. The method comprises the following steps: a) allowing a compound with a formula 1 as shown in the specification to react with a chlorinated reagent or a brominated reagent so asto obtain a compound with a formula 2 as shown in the specification; b) allowing the compound with the formula 2 as shown in the specification to react with phosphorus oxychloride in the presence of organic base so as to obtain a compound with a formula 3 as shown in the specification; and c) allowing the compound with the formula 3 as shown in the specification to react with a fluorinated reagentso as to obtain the compound with the formula 4 as shown in the specification. The invention also relates to a method for synthesizing the favipiravir by using the above-mentioned method.