4744-50-7

Basic information

• Product Name: 2,3-Pyrazinecarboxylic anhydride
• Synonyms: PYRAZINE-2,3-DICARBOXYLIC ANHYDRIDE;2,3-PYRAZINEDICARBOXYLIC ANHYDRIDE;2,3-PYRAZINECARBOXYLIC ANHYDRIDE;FURO[3,4-B]PYRAZINE-5,7-DIONE;2,3-Pyrazinedicarboxylic acid anhydride;Furo[3,4-b]pyrazine-5,7-dione (9CI);2,3-PYRAZINEDICARBOXLIC ANHYDRIDE;2,3-PYRAZINEDICARBOXYLICANHYDRATE
• CAS NO: 4744-50-7
• Molecular Formula: C₆H₂N₂O₃
• Molecular Weight: 150.09
• EINECS: 225-260-4
• Product Categories: GLYCINESCAFFOLD;Fused Ring Systems;Pesticide intermediates;NULL
• Mol File: 4744-50-7.mol
• Article Data: 9

Chemical Properties

• Melting Point: 210 °C (dec.)(lit.)
• Boiling Point: 357.3 °C at 760 mmHg
• Flash Point: 169.9 °C
• Appearance: white of off-white power
• Density: 1.686 g/cm³
• Vapor Pressure: 2.76E-05mmHg at 25°C
• Refractive Index: 1.634
• Storage Temp.: Inert atmosphere,Room Temperature
• Solubility: Actonitrile (Slightly), DMSO
• PKA: -3.43±0.20(Predicted)
• CAS DataBase Reference: 2,3-Pyrazinecarboxylic anhydride(CAS DataBase Reference)
• NIST Chemistry Reference: 2,3-Pyrazinecarboxylic anhydride(4744-50-7)
• EPA Substance Registry System: 2,3-Pyrazinecarboxylic anhydride(4744-50-7)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36
• WGK Germany: 3
• Hazardous Substances Data: 4744-50-7(Hazardous Substances Data)

Usage

Uses

2,?3-?Pyrazinedicarboxylic Anhydride is a reagent used in the synthesis of highly potent and selective abietane type diterpenoid amides.

InChI:InChI=1/C6H2N2O3/c9-5-3-4(6(10)11-5)8-2-1-7-3/h1-2H

Synthetic route

2,3-dicarboxypyrazine (89-01-0) → 2,3-pyrazinedicarboxylic anhydride (4744-50-7)

Conditions	Yield
With acetic anhydride for 0.0833333h;	94%
With acetic anhydride Heating;	93%
With acetic anhydride for 0.166667h; Heating;	83%

2,3-dicarboxypyrazine (89-01-0) + acetic anhydride (108-24-7) → 2,3-pyrazinedicarboxylic anhydride (4744-50-7)

Conditions	Yield
for 1h; Reflux;	70%

2,3-diethynylquinoxaline (91-19-0) → 2,3-pyrazinedicarboxylic anhydride (4744-50-7)

Conditions	Yield
(i) KMnO4, (ii) Ac2O; Multistep reaction;

methanol (67-56-1) + 2,3-pyrazinedicarboxylic anhydride (4744-50-7) → 3-[(methyloxy)carbonyl]-2-pyrazinecarboxylic acid (73763-86-7)

Conditions	Yield
for 12h; Ambient temperature;	100%
at 20℃; for 72h;	75%

acetamide (60-35-5) + 2,3-pyrazinedicarboxylic anhydride (4744-50-7) → N-acetylpyrazine-2-carboxamide (135742-53-9)

Conditions	Yield
for 4h; Reflux;	100%

5-chloro-2-pyridylamine (1072-98-6) + 2,3-pyrazinedicarboxylic anhydride (4744-50-7) → 3-((5-chloropyridin-2-yl)carbamoyl)pyrazine-2-carboxylic acid (43200-83-5)

Conditions	Yield
In tetrahydrofuran at 20℃; for 1h;	99%
In tetrahydrofuran at 20℃; for 1h;	99%
In dichloromethane at 5 - 20℃; for 3.5h; Product distribution / selectivity;
Stage #1: 5-chloro-2-pyridylamine; 2,3-pyrazinedicarboxylic anhydride In toluene at 20 - 52℃; for 2.5h; Stage #2: With hydrogenchloride In water at 10 - 15℃; for 1h;

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-amino-2,5-dimethoxy-N-phenylbenzamide (265332-93-2) → N-(2,5-dimethoxy-4-(phenylcarbamoyl)phenyl)pyrazine-2-carboxamide (1454692-94-4)

Conditions	Yield
In toluene for 12h; Inert atmosphere; Reflux;	99%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 1-Adamantanamine (768-94-5) → N-((3s,5s,7s)-adamantan-1-yl)pyrazine-2-carboxamide (405081-00-7)

Conditions	Yield
In toluene for 12h; Inert atmosphere; Reflux;	99%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + aniline (62-53-3) → N-(phenyl)pyrazine-2-carboxamide (34067-83-9)

Conditions	Yield
In toluene for 12h; Inert atmosphere; Reflux;	99%

tryptamine (61-54-1) + 2,3-pyrazinedicarboxylic anhydride (4744-50-7) → C16H14N4O3 (733761-59-6)

Conditions	Yield
In dichloromethane at 20℃; for 18h;	98%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + L-Valine ethyl ester hydrochloride (17609-47-1) → (S)-ethyl 3-methyl-2-(pyrazine-2-carboxamido)butanoate (1454692-95-5)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In toluene for 12h; Inert atmosphere; Reflux;	98%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-methoxy-aniline (104-94-9) → 3-[(4-methoxyphenyl)carbamoyl]pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 4-methoxy-aniline In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	98%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-aminoethylbenzene (589-16-2) → 3-[(4-ethylphenyl)carbamoyl]pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 4-aminoethylbenzene In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	98%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-chloro-aniline (106-47-8) → 3-((4-chlorophenyl)carbamoyl)pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 4-chloro-aniline In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	98%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + phenethylamine (64-04-0) → C6H2N2O2NCH2CH2C6H5

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.25h;	97%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 2-hydroxy-5-chloro-aniline (95-85-2) → 3-[(5-chloro-2-hydroxyphenyl)carbamoyl]pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 2-hydroxy-5-chloro-aniline In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	97%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 3-trifluoromethylaniline (98-16-8) → 3-{[3-(trifluoromethyl)phenyl]carbamoyl}pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 3-trifluoromethylaniline In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	97%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + benzylamine (100-46-9) → 6-benzyl-5H-pyrrolo[3,4-b]pyrazine-5,7(6H)-dione

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.25h;	96%
In acetic acid for 3h; Reflux;	90%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + ethylamine (75-04-7) → 6-ethyl-pyrrolo[3,4-b]pyrazine-5,7-dione (28769-74-6)

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.333333h;	96%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 9-ethyl-9H-carbazol-3-ylamine (132-32-1) → 3-((9-ethyl-9H-carbazol-3-yl)carbamoyl)pyrazine-2-carboxylic acid

Conditions	Yield
In tetrahydrofuran at 20℃; for 16h; Inert atmosphere;	96%
In tetrahydrofuran at 20℃;	96%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) → ammonium 3-carbamoylpyrazine-2-carboxylate (74688-61-2)

Conditions	Yield
With ammonia In tetrahydrofuran for 0.166667h; Ambient temperature;	95%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 3,4-dimethoxybenzylamine (5763-61-1) → C6H2N2O2NCH2C6H3(OCH3)2

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.333333h;	95%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 1-amino-naphthalene (134-32-7) → N-(1-naphthalen-1-yl)pyrazine-2-carboxamide (320582-41-0)

Conditions	Yield
In toluene for 12h; Inert atmosphere; Reflux;	95%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 2-amino-phenol (95-55-6) → 3-[(2-hydroxyphenyl)carbamoyl]pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 2-amino-phenol In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	95%

2-thioxo-4-thiazolidinone (141-84-4) + 2,3-pyrazinedicarboxylic anhydride (4744-50-7) → 7-[4-Oxo-2-thioxo-thiazolidin-(5Z)-ylidene]-7H-furo[3,4-b]pyrazin-5-one (79677-23-9)

Conditions	Yield
With acetic anhydride; triethylamine for 1h; Ambient temperature;	94%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-methoxy-benzylamine (2393-23-9) → C6H2N2O2NCH2C6H4OCH3

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.333333h;	94%
With acetic acid for 4h; Reflux;

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + (R)-1-phenyl-ethyl-amine (3886-69-9) → C6H2N2O2NCHCH3C6H5

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.5h;	94%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 2,4-difluorophenylamine (367-25-9) → 3-[(2,4-difluorophenyl)carbamoyl]pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 2,4-difluorophenylamine In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	94%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + (S)-1-phenyl-ethylamine (2627-86-3) → C6H2N2O2NCHCH3C6H5

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.5h;	93%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-pentylaniline (33228-44-3) → C6H2N2O2NC6H4(CH2)4CH3

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.25h;	93%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 4-chlorobenzylamine (104-86-9) → C6H2N2O2NCH2C6H4Cl

Conditions	Yield
With triethylamine; 3-diphenyloxyphosphinyl-2-oxazolidinone In acetonitrile at 40℃; for 0.5h;	92%

2,3-pyrazinedicarboxylic anhydride (4744-50-7) + 3-fluoro-6-methylaniline (367-29-3) → 3-[(5-fluoro-2-methylphenyl)carbamoyl]pyrazine-2-carboxylic acid

Conditions	Yield
Stage #1: 2,3-pyrazinedicarboxylic anhydride; 3-fluoro-6-methylaniline In tetrahydrofuran at 20℃; for 1h; Stage #2: With sodium hydrogencarbonate In tetrahydrofuran; water pH=6;	92%

Upstream product

• 91-19-0 2,3-diethynylquinoxaline 
• 89-01-0 2,3-dicarboxypyrazine 
• 108-24-7 acetic anhydride 

Downstream Products

• 79677-21-7 5-[7-Oxo-7H-furo[3,4-b]pyrazin-(5Z)-ylidene]-3-phenyl-thiazolidine-2,4-dione 
• 145047-52-5 2-(2'5'-difluorobenzoyl)pyrazine-3-carboxylic acid 
• 134150-50-8 2-(2-aminophenylcarbamoyl)-3-pyrazine-carboxylic acid 
• 133593-36-9 2-(pyrazin-2-yl)benzo[d]thiazole 
• 13480-40-5 pyrazino<2,3-d>pyrazinedione 
• 43200-83-5 3-((5-chloropyridin-2-yl)carbamoyl)pyrazine-2-carboxylic acid 
• 890826-92-3 N-{4-[2-(2-{[tert-butyl(dimethyl)silyl]oxy}ethyl)-3-oxomorpholin-4-yl]phenyl}-N'-(4-chlorophenyl)pyrazine-2,3-dicarboxamide 

Relevant articles and documents

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