28020-38-4

Usage

Uses

Used in Pharmaceutical and Agrochemical Synthesis:
2,3-Diamino-6-methoxypyridine is utilized as a key intermediate in the synthesis of various pharmaceuticals and agrochemicals. Its unique structure allows for the development of new compounds with improved therapeutic or pesticidal properties.
Used in Organic Chemistry:
In the realm of organic chemistry, 2,3-Diamino-6-methoxypyridine serves as a valuable building block for the creation of complex organic molecules. Its reactivity and functional groups make it suitable for a wide range of organic reactions and synthesis processes.
Used as a Chelating Agent in Catalysis and Metal-Organic Frameworks:
2,3-Diamino-6-methoxypyridine is employed as a chelating agent, forming coordination compounds with metal ions. This property makes it useful in catalysis, where it can enhance the efficiency and selectivity of chemical reactions. Additionally, it is used as a ligand in the construction of metal-organic frameworks, which have applications in gas storage, separation, and catalysis.
Used in Medicinal Applications:
2,3-Diamino-6-methoxypyridine is being researched for its potential biological activities and is under investigation for its use in medicinal applications. Its ability to interact with metal ions and form stable complexes may contribute to its potential as a therapeutic agent or a tool in drug delivery systems.

InChI:InChI=1/C6H9N3O.ClH/c1-10-5-3-2-4(7)6(8)9-5;/h2-3H,7H2,1H3,(H2,8,9);1H

Synthetic route

6-methoxy-3-nitropyridin-2-amine (73896-36-3) → 2,3-diamino-6-methoxypyridine (28020-38-4)

Conditions	Yield
With palladium on activated charcoal; hydrogen In methanol at 20℃; for 16h;	100%
With hydrogen; palladium 10% on activated carbon at 25℃; for 6h;	99%
With hydrogen; palladium on activated charcoal In ethanol under 760 Torr;

6-methoxypyridine-2,3-diamine dihydrochloride → 2,3-diamino-6-methoxypyridine (28020-38-4)

Conditions	Yield
With ammonia In water at 15℃; pH=7 - 8;	92%

2-amino-6-chloro-3-nitropyridine (27048-04-0) → 2,3-diamino-6-methoxypyridine (28020-38-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: 70 percent / NaOMe / 2 h / Heating 2: H2 / 10percent Pd/C / ethanol / 760 Torr View Scheme
Multi-step reaction with 2 steps 1: ethanol / 16 h / -15 - 20 °C 2: hydrogenchloride; tin(ll) chloride / 5 h / 50 °C View Scheme

2,6-dicholoro-3-nitropyridine (16013-85-7) → 2,3-diamino-6-methoxypyridine (28020-38-4)

Conditions	Yield
Multi-step reaction with 3 steps 1: ammonium hydroxide / 5 h / 50 °C 2: ethanol / 16 h / -15 - 20 °C 3: hydrogenchloride; tin(ll) chloride / 5 h / 50 °C View Scheme

2,6-dichloropyridine (2402-78-0) → 2,3-diamino-6-methoxypyridine (28020-38-4)

Conditions	Yield
Multi-step reaction with 4 steps 1: sulfuric acid; nitric acid / -15 - 150 °C 2: ammonium hydroxide / 5 h / 50 °C 3: ethanol / 16 h / -15 - 20 °C 4: hydrogenchloride; tin(ll) chloride / 5 h / 50 °C View Scheme

2-chloro-6-methoxy-3-nitropyridine (38533-61-8) → 2,3-diamino-6-methoxypyridine (28020-38-4)

Conditions	Yield
Multi-step reaction with 2 steps 1: ammonia / methanol / 18 h / 65 °C 2: hydrogen / palladium on activated charcoal / ethanol / 20 °C / 760.05 Torr View Scheme
Multi-step reaction with 2 steps 1: ammonia; ammonium hydroxide / methanol / 18 h / 65 °C 2: hydrogen; palladium on activated charcoal / ethanol / 760.05 Torr View Scheme

2,3-diamino-6-methoxypyridine (28020-38-4) + 4-cyanobenzaldehyde (105-07-7) → 2-(4-cyanophenyl)-5-methoxy-4-azabenzimidazole

Conditions	Yield
With sodium metabisulfite; dimethyl sulfoxide at 165℃; for 0.25h; Inert atmosphere; Sealed tube;	92%

5-(3,4,5-trimethoxybenzoyl)-1H-indole-3-carbaldehyde + 2,3-diamino-6-methoxypyridine (28020-38-4) → (3-(5-cethoxy-3H-imidazo[4,5-b]pyridin-2-yl)-1H-indol-5-yl)(3,4,5-trimethoxyphenyl)methanone

Conditions	Yield
With sodium metabisulfite In ethanol; water at 80℃; for 2h;	85%

2,3-diamino-6-methoxypyridine (28020-38-4) + benzyl chloroformate (501-53-1) → benzyl 2-amino-6-methoxypyridin-3-ylcarbamate (1040363-61-8)

Conditions	Yield
With N-ethyl-N,N-diisopropylamine In dichloromethane at 0℃; for 1h;	83%

formic acid (64-18-6) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 5-methoxy-1H-imidazo[4,5-b]pyridine

Conditions	Yield
at 105℃; for 8h;	78.6%

1-methyl-5-(3,4,5-trimethoxybenzoyl)-1H-indole-3-carbaldehyde (1427690-73-0) + 2,3-diamino-6-methoxypyridine (28020-38-4) → (3-(5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)-1-methyl-1H-indol-5-yl)(3,4,5-trimethoxyphenyl)methanone

Conditions	Yield
With sodium metabisulfite In ethanol; water at 80℃; for 2h;	73%

C21H21NO5 + 2,3-diamino-6-methoxypyridine (28020-38-4) → (1-ethyl-3-(5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)-1H-indol-5-yl)(3,4,5-trimethoxyphenyl)methanone

Conditions	Yield
With sodium metabisulfite In ethanol; water at 80℃; for 2h;	72%

1-(trifluoroacetyl)-4-piperidone (65220-86-2) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 1-(4-(2-amino-6-methoxypyridin-3-ylamino)piperidin-1-yl)-2,2,2-trifluoroethanone (1040363-59-4)

Conditions	Yield
With sodium tris(acetoxy)borohydride In chloroform at 25℃; for 3h;	70%

2-methoxy-4-(methylsulfanyl)benzoic acid (72856-73-6) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 5-Methoxy-2-(2-methoxy-4-methylsulfanyl-phenyl)-1H-imidazo[4,5-b]pyridine (127356-18-7)

Conditions	Yield
With trichlorophosphate 1.) RT, 0.5 h, 2.) reflux, 6 h;	52%

2,3-diamino-6-methoxypyridine (28020-38-4) + 1,1'-carbonyldiimidazole (530-62-1) → 5-methoxy-1H-imidazo[4,5-b]pyridin-2(3H)-one (1388046-13-6)

Conditions	Yield
With triethylamine In tetrahydrofuran at 20℃; for 2h; Inert atmosphere;	31%

2,3-diamino-6-methoxypyridine (28020-38-4) + ethyl 2-cyanoacetate (105-56-6) → 2-(5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)acetonitrile

Conditions	Yield
In N,N-dimethyl-formamide at 180℃; for 5h;	22.2%

glyoxylic acid ethyl ester (924-44-7) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 6-methoxypyrido[2,3-b]pyrazin-2(1H)-one + 6-methoxy-4H-pyrido[2,3-b]pyrazin-3-one (917344-37-7)

Conditions	Yield
In methanol at 20℃;	A n/a B 13%

oxalic acid (144-62-7) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 6-methoxy-1,4-dihydropyrido[2,3-b]pyrazine-2,3-dione (144435-07-4)

Conditions	Yield
With hydrogenchloride Heating; Yield given;

2,3-diamino-6-methoxypyridine (28020-38-4) → 6-Hydroxy-1,4-dihydro-pyrido[2,3-b]pyrazine-2,3-dione

Conditions	Yield
Multi-step reaction with 2 steps 1: 4N aq. HCl / Heating 2: 70 percent / 48percent aq. HBr / 4 h / Heating View Scheme

2,3-diamino-6-methoxypyridine (28020-38-4) → 6-Methoxy-7-nitro-1,4-dihydro-pyrido[2,3-b]pyrazine-2,3-dione

Conditions	Yield
Multi-step reaction with 2 steps 1: 4N aq. HCl / Heating 2: 62 percent / AcOH, Ac2O, HNO3 / 1 h / 90 °C View Scheme

2,3-diamino-6-methoxypyridine (28020-38-4) → 2-(4-Methanesulfinyl-2-methoxy-phenyl)-5-methoxy-1H-imidazo[4,5-b]pyridine (127356-01-8)

Conditions	Yield
Multi-step reaction with 2 steps 1: 52 percent / POCl3 / 1.) RT, 0.5 h, 2.) reflux, 6 h 2: 53 percent / m-chloroperbenzoic acid / CHCl3 / 1.5 h / -15 °C View Scheme

N-tert-butyloxycarbonylpiperidin-4-one (79099-07-3) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 2-amino-3-[(1-tert-butoxycarbonylpiperidin-4-yl)amino]-6-methoxypyridine

Conditions	Yield
Stage #1: N-tert-butyloxycarbonylpiperidin-4-one; 2,3-diamino-6-methoxypyridine With sodium tris(acetoxy)borohydride In 1,2-dichloro-ethane at 20℃; Stage #2: With sodium hydroxide In water; 1,2-dichloro-ethane

pyrazolo[1,5-a]pyridin-3-ylamine (137837-55-9) + 2,3-diamino-6-methoxypyridine (28020-38-4) → C19H15N9

Conditions	Yield
With dihydrogen peroxide In ethanol; water at 20℃; for 168h; pH=7;

2-ethyl-5-methyl-2H-3,4-diaminopyrazole (184172-99-4) + 2,3-diamino-6-methoxypyridine (28020-38-4) → C17H25N11

Conditions	Yield
With sodium hydroxide; ammonium cerium(IV) nitrate In water; acetonitrile for 4h;

2,4,5,6-tetraaminopyrimidine (1004-74-6) + 2,3-diamino-6-methoxypyridine (28020-38-4) → C13H17N15

Conditions	Yield
With sodium hydroxide; ammonium cerium(IV) nitrate In water; acetonitrile for 4h;

3-amino-7-dimethylaminopyrazolopyrimidine + 2,3-diamino-6-methoxypyridine (28020-38-4) → C21H23N13

Conditions	Yield
With dihydrogen peroxide In ethanol; water at 20℃; for 168h;

2,3-diamino-6-methoxypyridine (28020-38-4) + ethyl bromoacetate (105-36-2) → 6-(methyloxy)-1,4-dihydropyrido[2,3-b]pyrazin-3(2H)-one (1073633-84-7) + ethyl N-[2-amino-6-(methyloxy)-3-pyridinyl]glycinate (1073633-83-6)

Conditions	Yield
With potassium carbonate In acetonitrile at 20℃;
With potassium carbonate In acetonitrile at 20℃; Inert atmosphere;	A 15 %Spectr. B 75 %Spectr.
With potassium carbonate In acetonitrile at 20℃; Product distribution / selectivity;

2,3-diamino-6-methoxypyridine (28020-38-4) + ethyl bromoacetate (105-36-2) → ethyl N-[2-amino-6-(methyloxy)-3-pyridinyl]glycinate (1073633-83-6)

Conditions	Yield
With potassium carbonate In acetonitrile at 20℃;
With potassium carbonate In acetonitrile at 20℃; Inert atmosphere;

carbon disulfide (75-15-0) + 2,3-diamino-6-methoxypyridine (28020-38-4) → 5-methoxy-1,3-dihydro-2H-imidazo[4,5-b]pyridine-2-thione (113713-60-3)

Conditions	Yield
Stage #1: carbon disulfide; 2,3-diamino-6-methoxypyridine With sodium hydroxide In ethanol Reflux; Stage #2: With hydrogenchloride In ethanol	0.187 g
With potassium hydroxide In ethanol; water at 80℃;
With potassium hydroxide In ethanol; water for 12h; Reflux;	16.9 g
With potassium hydroxide In water at 70℃;

3-(4-methoxypyridin-2-yl) propionic acid (608880-87-1) + 2,3-diamino-6-methoxypyridine (28020-38-4) → C15H16N4O2 (608880-52-0)

Conditions	Yield
With polyphosphoric acid at 110 - 160℃;

2,3-diamino-6-methoxypyridine (28020-38-4) → 4-(2-{4-[(2,3-dihydro[1,4]dioxino[2,3-c]pyridin-7-ylmethyl)amino]piperidin-1-yl}ethyl)-6-methoxypyrido[2,3-b]pyrazin-3(4H)-one

Conditions	Yield
Multi-step reaction with 5 steps 1.1: methanol / 20 °C 2.1: sodium hydride / N,N-dimethyl-formamide; mineral oil / 0 - 20 °C 2.2: 20 °C 3.1: trifluoroacetic acid / dichloromethane / 0.5 h / 0 °C 4.1: methanol; chloroform / 3 h / 70 °C / Molecular sieve 5.1: sodium tris(acetoxy)borohydride / methanol; chloroform / 0 - 20 °C View Scheme

2,3-diamino-6-methoxypyridine (28020-38-4) → C23H26N6O4

Conditions	Yield
Multi-step reaction with 4 steps 1.1: methanol / 20 °C 2.1: sodium hydride / N,N-dimethyl-formamide; mineral oil / 0 - 20 °C 2.2: 20 °C 3.1: trifluoroacetic acid / dichloromethane / 0.5 h / 0 °C 4.1: methanol; chloroform / 3 h / 70 °C / Molecular sieve View Scheme

Upstream product

• 73896-36-3 6-methoxy-3-nitropyridin-2-amine 
• 1159824-73-3 6-methoxypyridine-2,3-diamine dihydrochloride 
• 38533-61-8 2-chloro-6-methoxy-3-nitropyridine 
• 27048-04-0 2-amino-6-chloro-3-nitropyridine 
• 2402-78-0 2,6-dichloropyridine 
• 16013-85-7 2,6-dicholoro-3-nitropyridine 

Downstream Products

• 1040363-61-8 benzyl 2-amino-6-methoxypyridin-3-ylcarbamate 
• 1438246-37-7 C₂₄H₂₃N₅O₄ 
• 1438246-06-0 C₂₄H₂₃N₅O₄ 
• 1073634-29-3 phenylmethyl 6-(methyloxy)-3-oxo-3,4-dihydropyrido[2,3-b]pyrazine-1(2H)-carboxylate 
• 1073634-23-7 4-(3-amino-3,4-dihydro-2H-pyrano[3,2-b]pyridin-7-yl)-6-(methyloxy)-1,4-dihydropyrido[2,3-b]pyrazin-3(2H)-one 
• 1073634-24-8 6-(methyloxy)-4-(3-{[(phenylmethyl)oxy]amino}-3,4-dihydro-2H-pyrano[3,2-b]pyridin-7-yl)-1,4-dihydropyrido[2,3-b]pyrazin-3(2H)-one 
• 1073634-22-6 6-(methyloxy)-4-(3-{[(phenylmethyl)oxy]amino}-3,4-dihydro-2H-pyrano[3,2-b]pyridin-7-yl)pyrido[2,3-b]pyrazin-3(4H)-one 
• 1073633-91-6 phenylmethyl 4-[6-({[(1,1-dimethylethyl)oxy]carbonyl}amino)-5,6,7,8-tetrahydro-2-quinazolinyl]-6-(methyloxy)-3-oxo-3,4-dihydropyrido[2,3-b]pyrazine-1(2H)-carboxylate 
• 1096666-10-2 5-methoxy-1H-imidazo[4,5-b]pyridine 
• 1075234-83-1 (1R)-1-({4-[([1,3]oxathiolo[5,4-c]pyridin-6-ylmethyl)amino]-1-piperidinyl}methyl)-1,2-dihydro-3H,8H-2a,5,8a-triazaacenaphthylene-3,8-dione benzoate 
• 1075237-89-6 phenylmethyl (1R)-1-{[4-({[(1,1-dimethylethyl)oxy]carbonyl}amino)-1-piperidinyl]methyl}-3,8-dioxo-1,2,3,4-tetrahydro-5H,8H-2a,5,8a-triazaacenaphthylene-5-carboxylate 
• 1075237-88-5 phenylmethyl (1S)-1-{[(methylsulfonyl)oxy]methyl}-3,8-dioxo-1,2,3,4-tetrahydro-5H,8H-2a,5,8a-triazaacenaphthylene-5-carboxylate 
• 1075237-80-7 phenylmethyl (1S)-1-(hydroxymethyl)-3,8-dioxo-1,2,3,4-tetrahydro-5H,8H-2a,5,8a-triazaacenaphthylene-5-carboxylate 
• 1388144-49-7 ethyl (1-{5-[3-chloro-4-(5-methoxy-3H-imidazo[4,5-b]pyridin-2-yl)phenyl]pyridin-2-yl}piperidin-4-yl)acetate 

Relevant academic research and scientific papers

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IMIDAZOLE DERIVATIVES

Described herein are compounds of formula I. The compounds of formula I act as DGAT1 inhibitors and can be useful in preventing, treating or acting as a remedial agent for hyperlipidemia, diabetes mellitus and obesity.