78-98-8

Basic information

• Product Name: Methylglyoxal
• Synonyms: 1,2-Propanedione;1-Ketopropionaldehyde;2-oxo-propana;2-oxo-propionaldehyd;Acetylformyl;alpha-Ketopropionaldehyde;CH3COCHO;Glyoxal, methyl
• CAS NO: 78-98-8
• Molecular Formula: C₃H₄O₂
• Molecular Weight: 72.06
• EINECS: 201-164-8
• Product Categories: Aldehydes;blocks;BuildingBlocks;Aliphatics;Building Blocks;C1 to C6;Carbonyl Compounds;Chemical Synthesis;Nutrition Research;Organic Building Blocks;Other Biochemical;Phytochemicals by Chemical Classification;Pyridines
• Mol File: 78-98-8.mol
• Article Data: 135

Chemical Properties

• Melting Point: 25 °C
• Boiling Point: 72 °C
• Flash Point: 2.468 ºC
• Appearance: Clear yellow to yellow-brown/Solution
• Density: 1.19 g/mL at 20 °C
• Vapor Pressure: 121mmHg at 25°C
• Refractive Index: n20/D 1.4209
• Storage Temp.: 2-8°C
• Water Solubility: >=10 g/100 mL at 17 ºC
• Sensitive: Air Sensitive
• Merck: 14,6081
• BRN: 906750
• CAS DataBase Reference: Methylglyoxal(CAS DataBase Reference)
• NIST Chemistry Reference: Methylglyoxal(78-98-8)
• EPA Substance Registry System: Methylglyoxal(78-98-8)

Safety Data

• Hazard Codes: Xn,Xi,C
• Statements: 22-36-35
• Safety Statements: 26-36-45-36/37/39
• RIDADR: UN 3265 8 / PGIII
• RTECS: UZ0700000
• TSCA: Yes
• Hazardous Substances Data: 78-98-8(Hazardous Substances Data)

Usage

Chemical Properties

Different sources of media describe the Chemical Properties of 78-98-8 differently. You can refer to the following data:
1. Methylglyoxal (MG, C3H4O2) is also known as 2-oxopropanal, pyruvaldehyde, pyruvic aldehyde, 2-ketopropionaldehyde, acetylformaldehyde, propanedione, or propionaldehyde, which is a clear yellow slightly viscous liquid with a pungent odor which polymerizes readily and forms a variety of cyclic and acyclic structures. It is faintly acidic to litmus. The solubility of methylglyoxal is more than 10 g/100 mL water at 17°C. In water, MG is present mostly in the mono and dihydrate forms, while non hydrated MG is only present in traces.
2. clear yellow to yellow-brown solution
3. Pyruvaldehyde has a characteristic, pungent, stinging odor with a pungent, caramellic, sweet flavor.

Description

Different sources of media describe the Description of 78-98-8 differently. You can refer to the following data:
1. Methylglyoxal is an organic compound formed as a side-product of several metabolic pathways. It has been proved to be an intermediate in the metabolism of acetone and its derivatives. It is produced to insure every cell's health, which is used commonly as a reagent in organic synthesis, as a flavoring agent, and in tanning. However, the most important application is in pharmaceuticals. Methylglyoxal is found in all honeys, especially in manuka honey, in which it has strong antibacterial and antiviral property. Methylglyoxal is transferred into the honey where it remains stable. Dietary Methylglyoxal found in Manuka Honey is resistant to heat, light, body fluids and enzymatic activity. This property makes MGO Manuka Honey superior to any other honey. Its anti-cancer potential has been already demonstrated in human body and it has proved to be effective to eradicate most cancer types.
2. Methylglyoxal (MG) is a highly reactive a-dicarbonyl compound that is primarily generated endogenously during glycolytic pathways (glucose and fructose metabolism) in cells and exogenously due to autoxidation of sugar, degradation of lipids, and fermentation during food and drink processing. Methylglyoxal polymerizes readily; it is hygroscopic and incompatible with strong oxidizing agents and bases. Methylglyoxal may be present as a free molecule in the diet or bound to biological materials, such as proteins, and as advanced glycation end products (AGEs), which are poorly absorbed. Methylglyoxal has been indicated in pathological events associated with hyperglycemia in both type 1 and type 2 diabetes and in other diabetic complications as either a direct toxin or as a precursor for AGEs. In animal studies, MG has been shown to induce tumorigenesis, but has also been reported as a tumoristatic agent. Methylglyoxal has been identified as the dominant antibacterial constituent of manuka honey.

Sources

Many food products, beverages, water, rain, clouds, fog water, and urban atmosphere as well as cigarette smoke represent exogenous sources of methylglyoxal. The origins of MG in food and beverages are sugars, the products of the Maillard reaction, lipids and microorganisms formed during industrial processing, cooking, and prolonged storage. In vivo Methylglyoxal can be formed in many enzymatic and nonenzymatic pathways. Enzymatic pathways include reactions catalyzed by triosephosphate isomerase, cytochrome P450 2E1, myeloperoxidase, and aminooxidase, whereas nonenzymatic pathways include decomposition of dihydroxyacetone phosphate (DAP), the Maillard reaction, oxidation of acetol, and lipid peroxidation.

References

https://en.wikipedia.org/wiki/Methylglyoxal https://pubchem.ncbi.nlm.nih.gov/compound/880#section=Top http://www.cancertreatmentsresearch.com/methilglyoxal/

Occurrence

Reported found in the dry distillate of Manilla copal. Also reported found in apple juice, orange juice, celery root, rutabaga, tomato, wheaten bread, white bread, roasted and raw turkey, cognac, roasted barley, beer, cocoa, coffee and roasted pecans.

Uses

Different sources of media describe the Uses of 78-98-8 differently. You can refer to the following data:
1. Organic synthesis, as of complex chemical com- pounds such as pyrethrins, tanning leather, flavor- ing.
2. Used in organic synthesis, as a flavoring agent, and in tanning leather. Commercial formulation is available as a 30% aqueous solution. No safety concern at current levels of intake when used as a flavoring agent.
3. Methylglyoxal solution has been used:to assess glyoxalase 1 (GLO1) enzymatic activityas an advanced glycation end (AGE) forming agent for the preparation of albumin in vitroto regulate anxiety like behavior in miceto induce peritoneal fibrosis in ratsto study the chromatographic retention characteristics of organic chemicals and metal DNA adductsfor intraplantar injection in mice to investigate peripheral and central components of methylglyoxal (MG)-transient receptor potential ankyrin 1 (TRPA1)-adenylyl cyclase 1 isoform (AC1) pathway

Preparation

By distilling a dilute solution of dihydroxyacetone from calcium carbonate; by oxidation of acetone with selenium dioxide; by heating dihydroxy acetone with phosphorus pentoxide; by warming isonitroso acetone with diluted H2SO4.

Definition

ChEBI: A 2-oxo aldehyde derived from propanal.

Taste threshold values

Taste characteristics at 0.1%: sweet, caramellic with a dairy creamy nuance

General Description

Clear yellow slightly viscous liquid with a pungent odor. Yellowish-green vapors. Faintly acidic to litmus.

Air & Water Reactions

Water soluble.

Reactivity Profile

Methylglyoxal polymerizes readily. Methylglyoxal is hygroscopic. Methylglyoxal is incompatible with strong oxidizing agents and bases. Methylglyoxal is an aldehyde. Aldehydes are frequently involved in self-condensation or polymerization reactions. These reactions are exothermic; they are often catalyzed by acid. Aldehydes are readily oxidized to give carboxylic acids. Flammable and/or toxic gases are generated by the combination of aldehydes with azo, diazo compounds, dithiocarbamates, nitrides, and strong reducing agents. Aldehydes can react with air to give first peroxo acids, and ultimately carboxylic acids. These autoxidation reactions are activated by light, catalyzed by salts of transition metals, and are autocatalytic (catalyzed by the products of the reaction). The addition of stabilizers (antioxidants) to shipments of aldehydes retards autoxidation.

Fire Hazard

Literature sources indicate that Methylglyoxal is nonflammable.

Flammability and Explosibility

Nonflammable

Environmental Fate

Methylglyoxal production and use as a chemical intermediate and flavoring agent may result in its release to the environment through various waste streams. If released into water, MG is not expected to adsorb to suspended solids and sediment based on the estimated Koc. Volatilization from water surfaces is not expected to be an important fate process based upon the estimated Henry’s Law constant. If released to soil, MG is expected to have very high mobility based upon an estimated Koc of 1 determined from the structure estimation method. Hydrolysis is not expected to be an important environmental fate process since this compound lacks functional groups that hydrolyze under environmental conditions. Methylglyoxal serves as a substrate for the isozymes E1, E2, and E3 of human aldehyde dehydrogenase. Oxidation of MG by these isozymes generated pyruvate. Methylglyoxal is a partially oxidized compound obtained from the tropospheric oxidation of numerous hydrocarbons, of both biogenic and anthropogenic origin. If released to the air, an estimated vapor pressure of 27 mm Hg at 25 ℃ indicates MG will exist solely as a vapor in the atmosphere. Vapor-phase MG will be degraded in the atmosphere by reaction with photochemically produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 30 h. Methylglyoxal absorbs light at wavelengths >290 nm and, therefore, is susceptible to direct photolysis by sunlight; half-lives of 2–4 h have been reported.

Purification Methods

Commercial 30% (w/v) aqueous solution is diluted to about 10% and distilled twice, taking the fraction boiling below 50o/20mm Hg. (This treatment does not remove lactic acid). [Beilstein 1 IV 3631.]

Toxicity evaluation

Endogenously formed MG modifies arginine and lysine residues in proteins that form AGEs, which have been associated with diabetic complications and some neurodegenerative diseases. In different cell lines, MG treatment has been shown to induce apoptosis as measured by nuclear fragmentation and apoptotic body formation, indicating an increase in apoptosis. At the mitochondrial level, exogenous MG is highly toxic as it promotes proliferation, swelling, and membrane derangement. In both in vitro and in vivo studies, MG treatment has been shown to significantly reduce antioxidant enzymes and elevate reactive oxygen species that lead to oxidative stress-mediated cell death. Genotoxicity has been observed in both in vivo and in vitro studies, as MG is capable of binding to cellular macromolecules and forming DNA adducts.

InChI:InChI=1/C3H4O2/c1-3(5)2-4/h2H,1H3

Synthetic route

hydroxy-2-propanone (116-09-6) → acetaldehyde (75-07-0) + acetic acid (64-19-7) + 2-oxopropanal (78-98-8)

Conditions	Yield
With oxygen at 300℃;	A 5.79% B 92.17% C 2.04%

hydroxy-2-propanone (116-09-6) → 2-oxopropanal (78-98-8)

Conditions	Yield
With iron(III) phosphate; oxygen In water at 200℃; Oxidation;	88%
With oxygen In methanol at 60℃; under 15001.5 Torr; for 6h;	18%
With copper (I) acetate

dihydroxyacetone (96-26-4) → 2-oxopropanal (78-98-8)

Conditions	Yield
With sulfuric acid In water at 109.84℃; for 2h; Time; Reagent/catalyst;	80%

acetone (67-64-1) → 2-oxopropanal (78-98-8)

Conditions	Yield
With selenium(IV) oxide at 80℃; for 12h;	74%
With sodium periodate; perchloric acid In water at 60℃; Rate constant;
With ruthenium trichloride; sodium periodate; perchloric acid In water at 40 - 60℃; Thermodynamic data; Mechanism; ΔE(excit.), ΔH(excit.), ΔS(excit.);

1,3,5-trimethyl-benzene (108-67-8) → 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	65.2%
With ozone

propylene glycol (57-55-6) → 2-oxopropanal (78-98-8)

Conditions	Yield
With tert.-butylhydroperoxide; vanadyl(IV) sulphate pentahydrate In water; acetonitrile at 20℃; for 6h; Green chemistry;	65%
With air; silver contact at 390℃;
With bromine; potassium carbonate

N-(2-oxopropoxy)phthalimide (32380-81-7) → phthalimide (136918-14-4) + 2-oxopropanal (78-98-8)

Conditions	Yield
at 400℃; under 0.01 Torr; for 2.77778E-06h; Kinetics; Temperature;	A 60% B 14%

glycerol (56-81-5) → 3-Hydroxypropanal (2134-29-4) + hydroxy-2-propanone (116-09-6) + 2-oxopropanal (78-98-8)

Conditions	Yield
In water at 400℃;	A 60% B 10% C 30%

m-xylene (108-38-3) → Glyoxal (131543-46-9) + 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	A 11.3% B 56.8%

D-Xylose (87-72-9, 608-45-7, 608-46-8, 608-47-9, 2460-44-8, 6748-95-4, 6763-34-4, 7261-26-9, 7283-06-9, 7283-07-0, 7296-55-1, 7296-56-2, 7296-58-4, 7296-59-5, 7296-60-8, 7296-61-9, 7296-62-0, 7322-30-7, 10257-31-5, 10257-32-6, 10257-33-7, 10257-34-8, 10257-35-9, 19982-83-3, 20242-88-0, 28697-53-2, 36562-42-2, 41546-41-2, 89299-64-9, 107655-34-5, 115794-06-4, 115794-07-5, 130550-15-1, 130606-21-2) → furfural (98-01-1) + dihydroxyacetone (96-26-4) + Glycolaldehyde (141-46-8) + 2-oxopropanal (78-98-8)

Conditions	Yield
With SO4(2-)/12 wt percent ZrO2-Al2O3/SBA-15 In water; toluene at 160℃; for 4h;	A 52.7% B n/a C n/a D n/a

Pyruvic aldehyde dimethyl acetal (6342-56-9) → 2-oxopropanal (78-98-8)

Conditions	Yield
With sulfuric acid for 0.416667h; Heating;	50%
With water Acidic conditions;	50%
With sulfuric acid

glycerol (56-81-5) → formic acid (64-18-6) + LACTIC ACID (849585-22-4) + acetic acid (64-19-7) + 2-oxo-propionic acid (127-17-3) + acrylic acid (79-10-7) + 2-oxopropanal (78-98-8)

Conditions	Yield
Stage #1: glycerol With sodium hydroxide; water at 300℃; for 1h; Compressed liquid(s); Stage #2: With sulfuric acid In water Product distribution / selectivity;	A n/a B 40% C n/a D n/a E n/a F n/a

Glyceraldehyde (56-82-6) → LACTIC ACID (849585-22-4) + 2-oxopropanal (78-98-8)

Conditions	Yield
With tin(ll) chloride In water at 109.84℃; under 22502.3 Torr; for 3h; Catalytic behavior; Inert atmosphere; Autoclave;	A 5% B 39%

para-xylene (106-42-3) → Glyoxal (131543-46-9) + 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	A 38.5% B 17.8%

o-xylene (95-47-6) → Glyoxal (131543-46-9) + 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	A 13.4% B 34.5%

1,2,4-Trimethylbenzene (95-63-6) → Glyoxal (131543-46-9) + 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; oxygen; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	A 8.5% B 34.3%

dihydroxyacetone (96-26-4) → LACTIC ACID (849585-22-4) + 2-oxopropanal (78-98-8)

Conditions	Yield
With MoO40W12(3-)*Al(3+) In water at 60℃; under 7500.75 Torr; for 20h; Autoclave; Inert atmosphere;	A 15% B 25%
With lutetium triflate In water at 109.84℃; for 1h; Reagent/catalyst;
With silica-supported titanium oxide In water at 130℃; for 3h; Kinetics; Reagent/catalyst;
In water at 90℃; for 4h; Catalytic behavior; Reagent/catalyst; Time;

glycerol (56-81-5) → LACTIC ACID (849585-22-4) + dihydroxyacetone (96-26-4) + 2-oxopropanal (78-98-8)

Conditions	Yield
With MoO40W12(3-)*Al(3+); oxygen In water at 60℃; under 7500.75 Torr; for 20h; Kinetics; Autoclave;	A 25% B 14.5% C 6.2%

Glyceraldehyde (56-82-6) → dihydroxyacetone (96-26-4) + 2-oxopropanal (78-98-8)

Conditions	Yield
With MoO40W12(3-)*Al(3+) In water at 60℃; under 7500.75 Torr; for 20h; Autoclave; Inert atmosphere;	A 25% B 9%

1-Phenylbut-1-en-3-one (122-57-6) → benzaldehyde (100-52-7) + 2-oxopropanal (78-98-8)

Conditions	Yield
With dihydrogen peroxide In water; acetonitrile at 20℃; under 760.051 Torr; for 5h;	A 24% B n/a

toluene (108-88-3) → Glyoxal (131543-46-9) + 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	A 23.7% B 18.6%

butanone (78-93-3) → ethene (74-85-1) + acetaldehyde (75-07-0) + acetone (67-64-1) + 2-oxopropanal (78-98-8)

Conditions	Yield
With serpentine at 300 - 445℃; Flow reactor;	A 5.6% B 10.1% C 22.4% D 6.2%
With serpentine at 300 - 500℃; Flow reactor;	A 13.9% B 18% C 16.7% D 8.7%
With sulfated zirconia with MgO at 300 - 500℃; Flow reactor;	A 6.2% B 12.5% C 14.3% D 5.4%

butanone (78-93-3) → acetone (67-64-1) + 2-oxopropanal (78-98-8)

Conditions	Yield
With sulfated zirconia at 300 - 445℃; Flow reactor;	A 19.6% B 5.2%
With sulfated zirconia with MgO at 300 - 445℃; Flow reactor;	A 17.8% B 6.6%
With silica-alumina with MgO at 300 - 445℃; Flow reactor;	A 5.2% B 5.3%

1,2,3-trimethylbenzene (526-73-8) → Glyoxal (131543-46-9) + 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	A 6.4% B 18.1%

glycerol (56-81-5) → dihydroxyacetone (96-26-4) + Glyceraldehyde (56-82-6) + 2-oxopropanal (78-98-8)

Conditions	Yield
With 3H(1+)*MoO40W12(3-); oxygen In water at 60℃; under 7500.75 Torr; for 20h; Autoclave;	A 16% B 14.9% C 8.4%

butanone (78-93-3) → acetaldehyde (75-07-0) + acetone (67-64-1) + 2-oxopropanal (78-98-8)

Conditions	Yield
With silica-alumina at 300 - 445℃; Flow reactor;	A 9.4% B 9.4% C 6%

2-methylpropenal (78-85-3) → 2-oxopropanal (78-98-8)

Conditions	Yield
With methyl nitrite; nitrogen(II) oxide at 24.84℃; under 740 Torr; Inert atmosphere; Photolysis;	8.4%

2,3-dimethylfuran (14920-89-9) → 3-methyl-4-oxo-2-pentenal (535-09-1) + Glyoxal (131543-46-9) + Glycolaldehyde (141-46-8) + dimethylglyoxal (431-03-8) + 2-oxopropanal (78-98-8)

Conditions	Yield
With hydroxyl radical; nitrogen(II) oxide at 22.84℃; under 735 Torr; Gas phase;	A 8% B n/a C n/a D n/a E n/a

pyridine (110-86-1) + 1-(diethylamino)propan-2-one (1620-14-0) + dibenzoyl peroxide (94-36-0) → diethylamine (109-89-7) + 2-oxopropanal (78-98-8)

4-methyleneoxetan-2-one (674-82-8) → 2-oxopropanal (78-98-8)

Conditions	Yield
With tetrachloromethane; ozone

2-oxopropanal (78-98-8) → LACTIC ACID (849585-22-4)

Conditions	Yield
With barium hydroxide octahydrate at 25℃; for 48h; Inert atmosphere;	100%
With scandium(III) chloride In water at 109.84℃; for 1h; Reagent/catalyst;	90%
With aluminum (III) chloride In water at 170℃; for 0.333333h; Autoclave;	87%

(S)-1-(4-methylphenyl)ethylamine (27298-98-2) + 2-oxopropanal (78-98-8) → N-[(S)-1-(4-methylphenyl)ethyl]-2-oxopropan-1-imine

Conditions	Yield
	100%

(S)-1-phenyl-ethylamine (2627-86-3) + 2-oxopropanal (78-98-8) → 2-oxo-N-[(S)-1-phenylethyl]propan-1-imine

Conditions	Yield
	100%

L-cysteine ethyl ester hydrochloride (868-59-7) + 2-oxopropanal (78-98-8) → 2-acetyl-4-ethoxycarbonylthiazolidine

Conditions	Yield
With sodium hydrogencarbonate In ethanol; water at 20℃; for 12h;	100%
With sodium hydrogencarbonate In ethanol; water at 20℃; for 18h; Inert atmosphere;
With sodium hydrogencarbonate In ethanol; water
With sodium hydrogencarbonate In ethanol; water at 20℃; for 18h;

phenylhydrazine (100-63-0) + 2-oxopropanal (78-98-8) → 1-(phenylhydrazono)-propan-2-one (5391-74-2)

Conditions	Yield
With acetic acid In water at 20℃;	100%
In water at 25℃; Inert atmosphere;	85%
With acetic acid In water at 20℃; for 1h;

N-benzylhydrazine hydrochloride (1073-62-7, 20570-96-1) + 2-oxopropanal (78-98-8) → 1-benzylhydrazonopropanone (109299-37-8)

Conditions	Yield
In water at 20℃;	100%

methylhydrazine (60-34-4) + 2-oxopropanal (78-98-8) → 1-(4-hydroxy-1,5-dimethyl-1H-pyrazol-3-yl)ethanone (85985-64-4)

Conditions	Yield
With acetic acid In water for 3h; Reflux;	100%

Benzylhydrazine (555-96-4) + 2-oxopropanal (78-98-8) → 1-benzylhydrazonopropanone (109299-37-8)

Conditions	Yield
In water	100%

ethylhydrazine (624-80-6) + 2-oxopropanal (78-98-8) → 2-oxopropanal ethylhydrazone

Conditions	Yield
In methanol; water at 0 - 20℃; for 2.75h;	99%

5-bromo-1H-indole (10075-50-0) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → 3-acetyl-4-(5-bromo-1H-indol-3-yl)hexane-2,5-dione

Conditions	Yield
In water at 80℃; for 5h;	99%

indole (120-72-9) + ethyl acetoacetate (141-97-9) + 2-oxopropanal (78-98-8) → ethyl 2-acetyl-3-(1H-indol-3-yl)-4-oxopentanoate

Conditions	Yield
In water at 80℃; for 5h;	99%

tertbutylhydrazine hydrochloride (7400-27-3) + 2-oxopropanal (78-98-8) → 1-(2-(tert-butyl)hydrazono)propan-2-one

Conditions	Yield
In water at 20℃; for 1.5h;	98%
In water at 20℃; for 2h;	85%
Stage #1: tertbutylhydrazine hydrochloride; 2-oxopropanal In water at 23℃; Stage #2: With sodium hydroxide In tert-butyl methyl ether; water

indole (120-72-9) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → 3-acetyl-4-(1H-indol-3-yl)hexane-2,5-dione

Conditions	Yield
In water at 80℃; for 5h; Solvent; Temperature; Time;	98%
With water In neat (no solvent) for 0.1h; Microwave irradiation; Green chemistry;

1H-indol-4-ol (2380-94-1) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → 3-acetyl-4-(4-hydroxy-1H-indol-3-yl)hexane-2,5-dione

Conditions	Yield
In water at 80℃; for 5h;	98%

6-fluoro-1H-indole (399-51-9) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → 3-acetyl-4-(6-fluoro-1H-indol-3-yl)hexane-2,5-dione

Conditions	Yield
In water at 80℃; for 5h;	98%

3-(4-Hydroxy-phenyl)-1-(2,4,6-trihydroxy-phenyl)-propan-1-on (60-82-2) + 2-oxopropanal (78-98-8) → 2-hydroxy-1-(2,4,6-trihydroxy-3-(1-hydroxy-2-oxopropyl)-5-(3-(4-hydroxyphenyl)propanoyl)phenyl)propan-1-one

Conditions	Yield
In aq. phosphate buffer at 37℃; for 2h; Darkness;	98%

3-(4-Hydroxy-phenyl)-1-(2,4,6-trihydroxy-phenyl)-propan-1-on (60-82-2) + 2-oxopropanal (78-98-8) → 2-hydroxy-1-(2,4,6-trihydroxy-3-(1-hydroxy-2-oxopropyl)-5-(3-(4-hydroxyphenyl)propanoyl)phenyl)propan-1-one + C21H22O9 + C21H22O9 + C18H18O7 + C18H18O7

Conditions	Yield
In aq. phosphate buffer at 37℃; for 24h;	A 98% B n/a C n/a D n/a E n/a

oxybis(diphenylborane) (4426-21-5) + benzamidine monohydrochloride (1670-14-0) + 2-oxopropanal (78-98-8) → 1-methyl-3,3,7-triphenyl-2,4-dioxa-8-aza-6-azonia-3-boratabicyclo{3.3.3}oct-6-ene (115438-37-4)

Conditions	Yield
With sodium hydroxide In ethanol room temp.; crystn. from reaction mixt., washing (ethanol, ether), or evapn., extraction (hot ethanol), crystn. on cooling; elem. anal.;	97%

2-phenyl-5-methylene-4,5-dihydrooxazole (146896-52-8) + 2-oxopropanal (78-98-8) → 3-hydroxy-4-(2-phenyloxazol-5-yl)butan-2-one (1616778-00-7)

Conditions	Yield
With C39H60N4O4*Ni(2+)*2BF4(1-)*6H2O In dichloromethane at 30℃; for 24h; enantioselective reaction;	97%

(S)-2-methylpropane-2-sulfinamide (343338-28-3) + 2-oxopropanal (78-98-8) → (SS,E)-N-(tert-butanesulfinyl)-1-iminopropan-2-one

Conditions	Yield
With copper(II) sulfate In dichloromethane at 23℃; for 24h; Inert atmosphere;	97%

n-propylhydrazine oxalate (6340-91-6) + 2-oxopropanal (78-98-8) → 2-oxopropanal propylhydrazone (1355228-90-8)

Conditions	Yield
Stage #1: n-propylhydrazine oxalate; 2-oxopropanal With acetic acid In water at 20℃; Stage #2: With sodium hydrogencarbonate In dichloromethane; water	96%

(S)-1-phenyl-ethylamine (2627-86-3) + 2-oxopropanal (78-98-8) → (1S,2S)-(-)-N1,N2-bis(1-phenylethyl)-1,2-propanediimine

Conditions	Yield
With sodium sulfate In diethyl ether; water at 20℃; for 24h;	96%

n-propylhydrazine (5039-61-2) + 2-oxopropanal (78-98-8) → 2-oxopropanal propylhydrazone (1355228-90-8)

Conditions	Yield
With acetic acid In water	96%

indole-6-carboxylic acid methyl ester (50820-65-0) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → methyl 3-(4-acetyl-2,5-dioxohexan-3-yl)-1H-indole-6-carboxylate

Conditions	Yield
In water at 80℃; for 5h;	96%

7-ethyl-1H-indole (22867-74-9) + acetylacetone (123-54-6) + 2-oxopropanal (78-98-8) → 3-acetyl-4-(7-ethyl-1H-indol-3-yl)hexane-2,5-dione

Conditions	Yield
In water at 80℃; for 5h;	96%

urea (57-13-6) + 2-oxopropanal (78-98-8) → 1-methyl-2,4,6,8-tetraazabicyclo[3.3.0]octan-3,7-dione (3720-96-5)

Conditions	Yield
With 1-hydroxyethylene-(1,1-diphosphonic acid) In water at 80℃; for 1h; Green chemistry;	96%

1,2-diamino-benzene (95-54-5) + 2-oxopropanal (78-98-8) → 2-methylquinoxaline (7251-61-8)

Conditions	Yield
In water for 0.0333333h; Isay condensation; microwave irradiation;	95%
Stage #1: 2-oxopropanal With sodium disulfite In water for 0.166667h; Addition; Stage #2: 1,2-diamino-benzene In water at 20℃; for 18h; Condensation; Cyclization;	91%
In water at 20℃; for 0.5h; Green chemistry;	85%

semicarbazide hydrochloride (563-41-7) + 2-oxopropanal (78-98-8) → methylglyoxal disemicarbazone (10200-47-2)

Conditions	Yield
With sodium acetate In water for 0.5h; Heating;	95%
Stage #1: semicarbazide hydrochloride With sodium acetate In ethanol for 0.333333h; Reflux; Stage #2: 2-oxopropanal for 0.583333h; Reflux;	89%
With water; potassium acetate

4-Nitrophenylene-1,2-diamine (99-56-9) + 2-oxopropanal (78-98-8) → 2-methyl-6-nitroquinoxaline (2942-02-1)

Conditions	Yield
Heating;	95%
In water for 1.5h; Reflux;	90%
In water	87%

N-tert-butyloxycarbonylpiperidin-4-one (79099-07-3) + 2-oxopropanal (78-98-8) → (S)-tert-butyl 3-[(1R)-1-hydroxy-2-oxopropyl]-4-oxopiperidine-1-carboxylate + tert-butyl 3-[1-hydroxy-2-oxopropyl]-4-oxopiperidine-1-carboxylate

Conditions	Yield
With C32H29N3O3S In water at 25℃; for 30h; Aldol Addition; enantioselective reaction;	A 95% B n/a

Upstream product

• 110-86-1 pyridine 
• 1620-14-0 1-(diethylamino)propan-2-one 
• 94-36-0 dibenzoyl peroxide 
• 674-82-8 4-methyleneoxetan-2-one 
• 108-89-4 picoline 
• 108-75-8 2,4,6-trimethyl-pyridine 
• 67-56-1 methanol 
• 118685-85-1 1-(5,5-dimethyl-[1,2,4]trioxolan-3-yl)-ethanone 
• 5774-26-5 methylglyoxal diethyl acetal 
• 6014-42-2 L-rhamnose 
• 187737-37-7 propene 
• 2436-84-2 2,6-dimethyl-hepta-1,3-diene 
• 50-99-7 glucose 
• 67-66-3 chloroform 

Downstream Products

• 431-03-8 dimethylglyoxal 
• 111562-90-4 1-morpholin-4-yl-butane-2,3-dione 2-phenylhydrazone 
• 13040-58-9 7-methylpterin 
• 16041-24-0 6-methylpteridin-4(3H)-one 
• 34244-80-9 7-Methyl-4-oxo-3,4-dihydro-pteridin 
• 19358-03-3 1-(1,3-dioxolan-2-yl)ethan-1-one 
• 930-62-1 2,4-Dimethylimidazole 
• 13040-58-9 2-amino-7-methyl-3H-pteridin-4-one 
• 872-79-7 2-hydroxymethyl-4-methylimidazole 
• 62848-02-6 2-Benzyl-4-hydroxy-3-methyl-2-cyclopentenone 
• 89711-70-6 1,1'-Methylethandiylidendinitrilo-bis-(3-nitro-guanidin) 
• 69766-87-6 2-phenyl-3-methyl-4-hydroxycyclopent-2-en-1-one 
• 6342-56-9 Pyruvic aldehyde dimethyl acetal 
• 822-36-6 4-methyl-1H-imidazole 

Relevant articles and documents

Degradation of oligosaccharides in nonenzymatic browning by formation of α-dicarbonyl compounds via a peeling off mechanism

The formation of α-dicarbonyl-containing substances and Amadori rearrangement products was studied in the glycine-catalyzed (Maillard reaction) and uncatalyzed thermal degradation of glucose, maltose, and maltotriose using o-phenylenediamine as trapping agent. Various degradation products, especially α-dicarbonyl compounds, are formed from carbohydrates with differing degrees of polymerization during nonenzymatic browning. The different Amadori rearrangement products, isomerization products, and α-dicarbonyls produced by the used carbohydrates were quantified throughout the observed reaction time, and the relevance of the different degradation pathways is discussed. In the Maillard reaction (MR) the amino-catalyzed rearrangement with subsequent elimination of water predominated, giving rise to hexosuloses with α-dicarbonyl structure, whereas under caramelization conditions more sugar fragments with an α-dicarbonyl moiety were formed. For the MR of oligosaccharides a mechanism is proposed in which 1,4-dideoxyosone is formed as the predominating α-dicarbonyl in the quasi-water-free thermolysis of di- and trisaccharides in the presence of glycine.

Methylglyoxal synthetase, enol-pyruvaldehyde, glutathione and the glyoxalase system

enol-Pyruvaldehyde (ePY or 2-hydroxypropenal, O=C(H)-C(OH)=CH2) a transient intermediate in the alkaline decomposition of the triosephosphates to methylglyoxal is now observed by UV and 1H NMR spectroscopy as the immediate product of the methylglyoxal synthetase (MGS) reaction: dihydroxyacetone-P → Pi + ePY → methylglyoxal (MG). Analysis of ePY formed from 1-13C- and (1R, 3S)-[1,3-2H]-DHAP establishes the stereochemical course of its formation by MGS. Its rate of ketonization is much too slow to be in the sequence required for the assay of MGS by coupling of the MG produced to glyoxalase I (Glx I): MG + glutathione (GSH) → (S)-lactylglutathione (D-LG). Instead, ketonization occurs by way of the hemithioacetal (HTA) formed between ePY and GSH, and could be either an enzymatic function of Glx I or occur nonenzymatically at an activated rate. Enzymatic ketonization was ruled out because the methyl group of D-LG formed from specifically labeled ePY is achiral. Chemical ketonization of ePY is activated by general bases, such as acetate, and by thiols such as GSH and 2-mercaptoethanol, which disrupt its stabilizing double bond conjugation as hemithioacetal (HTA) adducts. 2-Mercaptoacetate combines both functions, acting as the HTA adduct of ePY with the appended carboxylate group presumably positioned to promote abstraction of the enol proton and protonation of the enolate carbon at an accelerated rate. In the MGS-Glx I system (dihydroxyacetone-P → ePY, ePY + GSH → GS-ePY, GS-ePY → GS-MG, GS-MG → D-LG), the nonenzymatic 2nd and 3rd steps describe the catalytic role of GSH in the critical ketonization process and set the stage for its participation in the glyoxalase system.

Formation of pyruvaldehyde (2-oxopropanal) by oxidative dehydrogenation of hydroxyacetone

Various mixed oxides were tested as catalysts for oxidative dehydrogenation of hydroxyacetone to form pyruvaldehyde (2-oxopropanal). The best results were obtained from an iron phosphate with a P/Fe atomic ratio of 1.05. The yield of pyruvaldehyde reached 88%. The next best results were obtained from a supported heteropoly acid (H3PMo12O40). The other molybdenum- and vanadium-based oxide catalysts were not suitable. The effects of the composition and structure of iron phosphate and the effects of reaction variables on the formation of pyruvaldehyde were also studied.

Reactions of aminoguanidine with a-dicarbonyl compounds studied by electrospray ionization mass spectrometry

Aminoguanidine possesses extensive pharmacological properties. This drug is recognized as a powerful a-dicarbonyl scavenger. In order to better elucidate the reactivity of aminoguanidine with a-dicarbonyls, aminoguanidine was reacted with several aldehydic and diketonic a-dicarbonyls. Electrospray ionization mass spectrometry is a suitable technique to study chemical and biochemical processes and was selected for the purpose. In aminoguanidine reactions, triazines were detected and other compounds that have never been reported before were identified. Triazine precursor forms were detected, namely tetrahydrotriazines and singly dehydrated tetrahydrotriazines. Moreover, species with bicyclic ring structures and dehydrated forms were also identified in aminoguanidine reactions. These species appear to result from tetrahydrotriazines and triazines reactions with one dicarbonyl molecule. Experiments revealed that these bicyclic species, in particular the ones resulting from triazines reactivity, could exist in solution, since they were both identified in the reactions of aminoguanidine and of a selected triazine with the dicarbonyls studied. The results obtained with regard to aminoguanidine/triazines reactivities appear to support the capability of triazines to condensate and form polycyclic ring structures and also to support literature mechanistic data for dihydroimidazotriazines formation via dihydroxyimidazolidine-triazines. The data obtained in this study may prove to be valuable to complement solution information concerning the reactivity of amines with a-dicarbonyls, in particular.

Aminoacetone Metabolism by Semicarbazide-Sensitive Amine Oxidase in Rat Aorta

High speed (105,000/60 min) membrane fractions from rat aorta homogenates mobilized the aliphatic amine aminoacetone (AA) to methylglyoxal (MG) with a Km of 19 +/- 3 μM, and Vmax of 510 +/- 169 nmol MG/hr/mg protein. This deaminating activity appears to be due to a semicarbazide-sensitive amine oxidase (SSAO), which is associated with smooth muscle cells in blood vessels of the rat and other species. AA was a competitive inhibitor (Ki of 28 +/- 6 μM) of the metabolism of benzylamine, a synthetic amine often used as an assay substrate for SSAO. AA is produced endogenously from mitochondrial metabolism of threonine and glycine, and thus could be a physiological substrate for SSAO, whereas the production of MG by SSAO could have cytotoxic implications for cellular function.

Aerobic oxidation of aminoacetone, a threonine catabolite: Iron catalysis and coupled iron release from ferritin

Aminoacetone (AA) is a threonine and glycine catabolite long known to accumulate in cridu-chat and threoninemia syndromes and, more recently, implicated as a contributing source of methylglyoxal (MG) in diabetes mellitus. Oxidation of AA to MG, NH4+, and H2O2 has been reported to be catalyzed by a copper-dependent semicarbazide sensitive amine oxidase (SSAO) as well as by Cu(II) ions. We here study the mechanism of AA aerobic oxidation, in the presence and absence of iron ions, and coupled to iron release from ferritin. Aminoacetone (1-7 mM) autoxidizes in Chelex-treated phosphate buffer (pH 7.4) to yield stoichiometric amounts of MG and NH4+. Superoxide radical was shown to propagate this reaction as indicated by strong inhibition of oxygen uptake by superoxide dismutase (SOD) (1-50 units/mL; up to 90%) or semicarbazide (0.5-5 mM; up to 80%) and by EPR spin trapping studies with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), which detected the formation of the DMPO-·OH adduct as a decomposition product from the DMPO-O2·- adduct. Accordingly, oxygen uptake by AA is accelerated upon addition of xanthine/xanthine oxidase, a well-known enzymatic source of O2·- radicals. Under Fe(II)EDTA catalysis, SOD (· enoyl radical. In the presence of iron, simultaneous (two) electron transfer from both Fe(II) and AA to O2, leading directly to H2O2 generation followed by the Fenton reaction is thought to take place. Aminoacetone was also found to induce dose-dependent Fe(II) release from horse spleen ferritin, putatively mediated by both O2·- and AA· enoyl radicals, and the co-oxidation of added hemoglobin and myoglobin, which may be viewed as the initial step for potential further iron release. It is thus tempting to propose that AA, accumulated in the blood and other tissues of diabetics, besides being metabolized by SSAO, may release iron and undergo spontaneous and iron-catalyzed oxidation with production of reactive H2O2 and O2·-, triggering pathological responses. It is noteworthy that noninsulin-dependent diabetes has been frequently associated with iron overload and oxidative stress.

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Catalytic wet air oxidation of D-glucose by perovskite type oxides (Fe, Co, Mn) for the synthesis of value-added chemicals

The conversion of common biomasses derived, as D-glucose, into value-added chemicals has received highest attention in the last few years. Among all processes, the catalytic wet air oxidation (CWAO) of derived biomasses using noble metal-based heterogeneo

Maillard Browning Inhibition by Ellagic Acid via Its Adduct Formation with the Amadori Rearrangement Product

The Maillard reaction performed under a stepwise increase of temperature was applied for researching the inhibition of Maillard browning caused by ellagic acid. Ellagic acid was found effective for the inhibition of melanoidin formation in the xylose-glycine Maillard reaction but depended on its dosage and the point of time it was added in the reaction system. The lightest color of the Maillard reaction products was observed when ellagic acid was added at the 90th min, which was the point of time when the Amadori rearrangement product (ARP) developed the most. LC-ESI-MS/MS analysis results showed a significant tendency of the ellagic acid hydrolysis product to react with the predominant intermediate ARP to yield an adduct. The adduct stabilized the ARP and delayed its decomposition and inhibited the downstream reactions toward browning. After the ARP was depleted, ellagic acid also showed an effect on scavenging some short-chain dicarbonyls which contributed to the inhibition of Maillard browning.

PROCESSES FOR THE PYROLYSIS OF CARBOHYDRATES

Various processes for the pyrolysis of carbohydrates to prepare products such as glycolaldehyde are described. Also, various catalysts and processes for preparing catalysts useful for carbohydrate pyrolysis are described.