6642-31-5

Basic information

• Product Name: 6-Amino-1,3-dimethyl-1,2,3,4-tetrahydropyrimidine-2,4-dione
• Synonyms: AURORA KA-4912;1,3-DIMETHYL-6-AMINOURACIL;1,3-DIMETHYL-4-AMINOURACIL;1,3-DIMETHYL-2,6-DIOXO-4-AMINOTETRAHYDROPYRIMIDINE;6-AMINO-1,3-DIMETHYLPYRIMIDINE-2,4(1H,3H)-DIONE;6-AMINO-1,3-DIMETHYLURACIL;6-AMINO-1,3-DIMETHYLURICIL;6-AMINO-1,3-DIMETHYL-1,2,3,4-TETRAHYDROPYRIMIDINE-2,4-DIONE
• CAS NO: 6642-31-5
• Molecular Formula: C₆H₉N₃O₂
• Molecular Weight: 155.15
• EINECS: 229-662-0
• Product Categories: Amines;Building Blocks;Heterocyclic Building Blocks;Pyrimidines
• Mol File: 6642-31-5.mol
• Article Data: 32

Chemical Properties

• Melting Point: 295 °C (dec.)(lit.)
• Boiling Point: 243.1 °C at 760 mmHg
• Flash Point: 100.8 °C
• Appearance: /
• Density: 1.288 g/cm³
• Vapor Pressure: 0.0328mmHg at 25°C
• Refractive Index: 1.55
• Storage Temp.: Store below +30°C.
• Solubility: 6g/l
• PKA: 5.17±0.70(Predicted)
• Water Solubility: 7.06g/L(25 oC)
• CAS DataBase Reference: 6-Amino-1,3-dimethyl-1,2,3,4-tetrahydropyrimidine-2,4-dione(CAS DataBase Reference)
• NIST Chemistry Reference: 6-Amino-1,3-dimethyl-1,2,3,4-tetrahydropyrimidine-2,4-dione(6642-31-5)
• EPA Substance Registry System: 6-Amino-1,3-dimethyl-1,2,3,4-tetrahydropyrimidine-2,4-dione(6642-31-5)

Safety Data

• Hazard Codes: Xn
• Statements: 22-36/37/38
• Safety Statements: 22-26-36/37/39
• WGK Germany: 1
• RTECS: YQ8755000
• Hazardous Substances Data: 6642-31-5(Hazardous Substances Data)

Usage

Uses

6-Amino-1,3-dimethyluracil is used as a reagent in the synthesis of new pyrimidine and caffeine derivatives that display highly potential antitumor activity. It is also used as a starting material in the synthesis of fused pyrido-pyrimidines.

InChI:InChI=1/C6H9N3O2/c1-8-4(7)3-5(10)9(2)6(8)11/h3H,7H2,1-2H3

Synthetic route

N,N'-Dimethylurea (96-31-1) + acetic anhydride (108-24-7) + cyanoacetic acid (372-09-8) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
at 60℃; for 3h;	96%

4-Amino-2,6-dihydroxypyrimidine (873-83-6) + methyl iodide (74-88-4) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
Stage #1: 4-Amino-2,6-dihydroxypyrimidine With potassium hydroxide In ethanol for 0.666667h; Heating; Stage #2: methyl iodide In ethanol for 8h; Heating;	90%
With sodium hydroxide
Stage #1: 4-Amino-2,6-dihydroxypyrimidine With sodium hydride In dimethyl sulfoxide for 13h; Stage #2: methyl iodide In dimethyl sulfoxide for 0.75h; Time;

6-azido-1,3-dimethylpyrimidine-2,4(1H,3H)-dione (61541-41-1) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
In tetralin at 150℃; for 0.0833333h;	90%
With hydrogen; palladium on activated charcoal In methanol for 1h; Ambient temperature;	85%
Multi-step reaction with 2 steps 1: 94 percent / toluene / 0.5 h / Heating 2: 62 percent / aq. AcOH, CF3COOH / 6 h / Heating View Scheme

N,N'-Dimethylurea (96-31-1) + cyanoacetic acid (372-09-8) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
Stage #1: N,N'-Dimethylurea; cyanoacetic acid With acetic anhydride at 60℃; for 0.166667h; microwave irradiation; Stage #2: With sodium hydroxide In ethanol at 20℃;	80%
With sodium ethanolate for 4h; Reflux;	80%
In acetic anhydride at 60℃; for 3h; Inert atmosphere;	79%

1-(2-cyanoacetyl)-1,3-dimethyl-urea (39615-79-7) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With chloro-trimethyl-silane; 1,1,1,3,3,3-hexamethyl-disilazane for 24h; Cyclization; Heating;	79%
With sodium hydroxide	70%
With potassium acetate

1,3-dimethyl-2,4-dioxo-6-<(triphenylphosphoranylidene)amino>-1,2,3,4-tetrahydropyrimidine (99747-54-3) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With acetic acid; trifluoroacetic acid for 6h; Heating;	62%

6-amino-1,3-dimethyl-5-formyluracil (54660-80-9) + edaravone (89-25-8) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 1-phenyl-3-methyl-4-(1-phenyl-3-methyl-5-oxo-4-pyrazolylidene)methylene-5-pyrazolone (4702-90-3)

Conditions	Yield
With piperidine In ethanol at 20℃; for 1h;	A 60% B n/a

5,7-Dimethylpyrimido<4.5-e>-1,2,4-triazinedione, isofervenulin (16044-79-4) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 1,3-dimethyl-5-phenyl-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-2,4-dione (59797-01-2)

Conditions	Yield
With diethylamine; acetophenone at 100 - 110℃; for 3h;	A 19% B 56%

5,7-Dimethylpyrimido<4.5-e>-1,2,4-triazinedione, isofervenulin (16044-79-4) + acetophenone (98-86-2) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 1,3-dimethyl-5-phenyl-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-2,4-dione (59797-01-2)

Conditions	Yield
With diethylamine at 100 - 110℃; for 3h;	A 19% B 56%

N,N'-Dimethylurea (96-31-1) + ethyl 2-cyanoacetate (105-56-6) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium methylate In methanol for 5h; Heating;	36%

4-Amino-2,6-dihydroxypyrimidine (873-83-6) + dimethyl sulfate (77-78-1) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium hydroxide
With sodium hydroxide In water for 4.2h;

6-amino-1-methyluracil (2434-53-9) + dimethyl sulfate (77-78-1) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium hydroxide

1,1-Dimethylurea (598-94-7) + cyanoacetic acid chloride (16130-58-8) → 1,3-dimethylbarbituric acid (769-42-6) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

1,1-Dimethylurea (598-94-7) + cyanoacetic acid (372-09-8) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With pyridine; trichlorophosphate

1,1-Dimethylurea (598-94-7) + ethyl 2-cyanoacetate (105-56-6) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium ethanolate
With sodium amide; xylene at 100 - 120℃;

N,N'-Dimethylurea (96-31-1) + methyl 2-cyanoacetate (105-34-0) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium butanolate; butan-1-ol

dimethyl sulfate (77-78-1) + 1-methyl-barbituric acid imide-(6) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium hydroxide

methyl iodide (74-88-4) + 1-methyl-barbituric acid imide-(6) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium hydroxide

N-cyanoacetyl-N'-methyl-urea (6972-77-6) → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
Multi-step reaction with 2 steps 1: aq. NaOH solution; NaOH 2: aq. NaOH solution View Scheme

4-Amino-2,6-dihydroxypyrimidine (873-83-6) + methyl halide → 6-Amino-1,3-dimethylbarbituric acid (6642-31-5)

Conditions	Yield
With sodium hydride In N,N-dimethyl-formamide; mineral oil at 70℃; for 3h;

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) → 6-amino-1,3-dimethyl-5-nitroso-1H-pyrimidine-2,4-dione (6632-68-4)

Conditions	Yield
With acetic acid; sodium nitrite In water	100%
With isopentyl nitrite In ethanol at 20℃; Solvent; Reagent/catalyst; Large scale;	90%
With acetic acid; sodium nitrite In water at 80℃; for 1h;	89%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 6-amino-1,3-dimethyl-5-formyluracil (54660-80-9) → 1,3,7,9-tetramethyl-2,4,6,8-tetraoxopyrido[2,3-d][6,5-d']dipyrimidine (796-39-4)

Conditions	Yield
In tetralin at 190 - 195℃; for 1h;	99%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + cyanoacetic acid (372-09-8) → 2-(6-amino-1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-ylcarbonyl)acetonitrile (112735-05-4)

Conditions	Yield
With acetic anhydride at 90℃; for 0.0833333h;	99%
With acetic anhydride at 80℃;	95%
With acetic anhydride at 84.84℃; for 0.166667h;	87%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + diethyl 2-ethoxymethylenemalonate (87-13-8) → Diethyl N-(1,3-Dimethyl-2,4-dioxo-6-pyrimidinyl)aminomethylenemalonate (104312-63-2)

Conditions	Yield
With sodium ethanolate In ethanol Heating; overnight;	99%
With sodium ethanolate In ethanol Gould-Jacobs reaction;

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-methyl-benzaldehyde (104-87-0) → 1-(4-methylphenyl)-1-bis(6-amino-1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimid-5-yl)methane (73038-86-5)

Conditions	Yield
In water at 20℃; for 0.25h; chemoselective reaction;	99%
With hybrid material nanorod-[SiO2-Pr-Im-SO3H][TFA] In ethanol for 1h; Catalytic behavior; Reflux;	96%
With [2-(dimethylamino)ethyl]dimethylazanium phosphoric acid chloride functionalized Fe3O4-SiO2core-shell magnetic nanoparticles at 120℃; for 0.166667h;	95%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-chlorobenzaldehyde (104-88-1) → 1-(4-chlorophenyl)-1-bis(6-amino-1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropyrimid-5-yl)methane (73050-30-3)

Conditions	Yield
In water at 20℃; for 0.25h; chemoselective reaction;	99%
In ethanol; water at 20℃; for 1h;	99%
With [2-(dimethylamino)ethyl]dimethylazanium phosphoric acid chloride functionalized Fe3O4-SiO2core-shell magnetic nanoparticles at 120℃; for 0.333333h; Temperature;	97%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + dimedone (126-81-8) + 4-bromo-benzaldehyde (1122-91-4) → 1,3,8,8-tetramethyl-5-(4-bromophenyl)-5,8,9,10-tetrahydropyrimido[4,5-b]quinoline-2,4,6(1H,3H,7H)-trione (339370-14-8)

Conditions	Yield
With N-methyl-2-oxopyrrolidin-1-ium dihydrogen phosphate at 80℃; for 0.833333h;	99%
With zirconium hydrogen sulfate In neat (no solvent) at 80℃; for 1h;	97%
With 1,4‑diazabicyclo[2.2.2]octane‑1,4‑diium hydrogen sulfate In ethanol; water at 75℃; for 1.33333h; Green chemistry;	95%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-nitro-aniline (100-01-6) → 6-amino-1,3-dimethyl-5-(4-nitrophenylazo)-1H-pyrimidine-2,4-dione (65357-92-8)

Conditions	Yield
Stage #1: 4-nitro-aniline With sulfuric acid; acetic acid; sodium nitrite at 0 - 5℃; for 2h; Stage #2: 6-Amino-1,3-dimethylbarbituric acid With sodium hydroxide In water at 0 - 5℃; for 0.25h; pH=7;	99%
Stage #1: 4-nitro-aniline With hydrogenchloride; sodium nitrite at 0 - 5℃; Stage #2: 6-Amino-1,3-dimethylbarbituric acid With sodium hydrogencarbonate; acetic acid In water at 0 - 5℃; pH=6 - 7;	97%
Stage #1: 4-nitro-aniline With water; sodium nitrite at 20℃; Stage #2: 6-Amino-1,3-dimethylbarbituric acid at 20℃;	77%
Stage #1: 4-nitro-aniline With hydrogenchloride; sodium nitrite In water at 0 - 5℃; for 0.5h; Stage #2: 6-Amino-1,3-dimethylbarbituric acid With acetic acid In water at 0 - 5℃; for 0.5h; Stage #3: With sodium hydroxide at 20℃; for 1h; pH=Ca. 5 - 6;

furfural (98-01-1) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) → 6,6'-diamino-1,1',3,3'-tetramethyl-5,5'-(2-furyl)bis[pyrimidine-2,4(1H,3H)-dione] (1298131-02-8)

Conditions	Yield
In water at 20℃; for 1h; chemoselective reaction;	99%
In ethanol; water at 20℃; for 3h;	99%
With ammonium cerium (IV) nitrate In ethanol; water at 20℃; for 2h; Green chemistry;	94%

2,4-thiazolidinedion (2295-31-0) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + ortho-bromobenzaldehyde (6630-33-7) → 9-(2-bromophenyl)-5,7-dimethyl-5,9-dihydrothiazolo[5',4':5,6]pyrido[2,3-d]pyrimidine-2,6,8(3H,4H,7H)-trione

Conditions	Yield
With layered double hydroxides functionalized with (3r,5r,7r)-1-(3-(triethoxysilyl)propyl)-1,3,5,7-tetraazaadamantan-1-ium chloride In water at 100℃; for 0.333333h; Green chemistry;	99%

2,4-thiazolidinedion (2295-31-0) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 2-Fluorobenzaldehyde (446-52-6) → 9-(2-fluorophenyl)-5,7-dimethyl-5,9-dihydrothiazolo[5',4':5,6]pyrido[2,3-d]pyrimidine-2,6,8(3H,4H,7H)-trione

Conditions	Yield
With layered double hydroxides functionalized with (3r,5r,7r)-1-(3-(triethoxysilyl)propyl)-1,3,5,7-tetraazaadamantan-1-ium chloride In water at 100℃; for 0.0833333h; Green chemistry;	99%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + oct-3-yn-2-one (1119-58-0) → 5-n-butyl-1,3,7-trimethylpyrido[2,3-d]pyrimidine-2,4-dione

Conditions	Yield
With potassium cyanide; sodium hydroxide; carbon monoxide; nickel cyanide at 24℃; for 0.5h;	98.6%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + N,N-dimethyl-formamide dimethyl acetal (4637-24-5) → 6-<<(dimethylamino)methylene>amino>-1,3-dimethyluracil (120788-53-6)

Conditions	Yield
for 5h; Inert atmosphere; Reflux;	98%
for 0.05h; Microwave irradiation;	95%
for 5h; Reflux;	78%
In benzene for 6h; Heating;	66%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + N,N-dimethyl-formamide (68-12-2, 33513-42-7) → 6-amino-1,3-dimethyl-5-formyluracil (54660-80-9)

Conditions	Yield
With trichlorophosphate at 49.84 - 59.84℃; for 0.25h;	98%
With trichlorophosphate at 100℃; for 1h;	90%
With trichlorophosphate Vilsmeier formylation;
Stage #1: 6-Amino-1,3-dimethylbarbituric acid; N,N-dimethyl-formamide at 0℃; for 0.166667h; Stage #2: With trichlorophosphate at 20℃; for 2h;	219.8 mg

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidine-5-carbaldehyde (4869-46-9) → 6-<(1,3-dimethylureido)carbonyl>-1,3-dimethyl-1,2,3,4-tetrahydropyrido<2,3-d>pyrimidine-2,4(1H,3H)-dione

Conditions	Yield
With acetic acid for 6h; Reflux;	98%
With trifluoroacetic acid In acetonitrile Heating;	67%

1H-indene-1,3(2H)-dione (606-23-5) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-bromo-benzaldehyde (1122-91-4) → 1,3-dimethyl-5-(4-bromophenyl)-1H-indeno[2',1':5,6]pyrido[2,3-d]pyrimidine-2,4,6(3H)-trione

Conditions	Yield
With zirconium hydrogen sulfate In neat (no solvent) at 80℃; for 1h;	98%
With Fe3O4*cellulose sulfuric acid In water at 80℃; for 0.5h; Green chemistry;	95%
With nano Fe2O3(at)SiO2-SO3H In water for 2h; Reflux;	95%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) → 6-Amino-5-iodo-1,3-dimethyl-1H-pyrimidine-2,4-dione

Conditions	Yield
With bis(acetylacetonate)oxovanadium; dihydrogen peroxide; acetic acid; potassium iodide In ethanol; water at 20℃; for 0.166667h; Catalytic behavior; Reagent/catalyst; Concentration; Time;	98%
Multi-step reaction with 2 steps 1: 83 percent / CH2Cl2 / 2 h / Ambient temperature 2: 48 percent / acetonitrile / 8 h / Heating View Scheme

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-chlorobenzaldehyde (104-88-1) + dimedone (126-81-8) → 1,3,8,8-tetramethyl-5-(4-chlorophenyl)-5,8,9,10-tetrahydropyrimido[4,5-b]quinoline-2,4,6(1H,3H,7H)-trione (810629-01-7)

Conditions	Yield
With N-methyl-2-oxopyrrolidin-1-ium dihydrogen phosphate at 80℃; for 0.833333h;	98%
With nano-[Fe3O4(at)-SiO2(at)R-NHMe2][H2PO4] catalyst In neat (no solvent) at 120℃; for 0.166667h; Temperature; Green chemistry;	96%
With nano-[Fe3O4(at)SiO2(at)BDIL] In neat (no solvent) at 120℃; for 0.25h; Reagent/catalyst; Temperature; Time;	96%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + dimedone (126-81-8) + 2,4-dichlorobenzaldeyhde (874-42-0) → 5-(2,4-dichlorophenyl)-1,3,8,8-tetramethyl-7,8,9,10-tetrahydropyrimido[4,5-b]quinoline-2,4,6(1H,3H,5H)-trione (881615-40-3)

Conditions	Yield
With 1-n-butyl-3-methylimidazolim bromide at 95℃; for 4h;	98%
With N,N,N',N'-tetramethyl-N-(silica-n-propyl)-N'-sulfonic acid-ethylenediaminium chloride/mesylate ([TSSECM]) In neat (no solvent) at 125℃; for 0.5h;	93%
With rhodium(III) chloride hydrate In water at 40℃; for 0.05h; Sonication; Green chemistry;	92%
With nano-[Fe3O4(at)SiO2(at)BDIL] In neat (no solvent) at 120℃; for 0.25h;	85%
With N,N,N-triethyl-N-sulfoethanammonium chloride In neat (no solvent) at 120℃; for 0.5h; Green chemistry;

2-aminopyrimidine (109-12-6) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) → 6-amino-1,3-dimethyl-5-[(2-pyrimidyl)diazenyl]uracil (1242060-34-9)

Conditions	Yield
Stage #1: 2-aminopyrimidine With sulfuric acid; acetic acid; sodium nitrite at 0 - 5℃; for 2h; Stage #2: 6-Amino-1,3-dimethylbarbituric acid With sodium hydroxide In water at 0 - 5℃; for 0.25h; pH=7;	98%

BARBITURIC ACID (67-52-7) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-chlorobenzaldehyde (104-88-1) → 1,3-dimethyl-5-(4-chlorophenyl)-5,10-dihydropyrimido[5',4':5,6]pyrido[2,3-d]pyrimidine-2,4,6,8(1H,3H,7H,9H)-tetraone (1207379-31-4)

Conditions	Yield
With zirconium hydrogen sulfate In neat (no solvent) at 80℃; for 1h;	98%
With hexamethylenetetramine-based ionic liquid immobilized on the MIL-101(Cr) metal-organic framework In neat (no solvent) at 80℃; for 0.233333h;	95%
With piperidine In water at 60℃; for 1h; Ultrasound irradiation;	87%
With phosphorus pentoxide In ethanol for 2h; Reflux;	80%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + Benzoylacetonitrile (614-16-4) + 4-bromo-benzaldehyde (1122-91-4) → 5-(4-Bromophenyl)-1,3-dimethyl-2,4-dioxo-7-phenyl-1,2,3,4-tetrahydropyrido[2,3-d]pyrimidine-6-carbonitrile (1258793-95-1)

Conditions	Yield
With 1-n-butyl-3-methylimidazolim bromide at 80℃; for 5.5h;	98%
In water at 90℃; for 8h; Green chemistry;	97%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-nitrobenzaldehdye (555-16-8) + dimedone (126-81-8) → 5-(4-nitrophenyl)-1,3,8,8-tetramethyl-7,8,9,10-tetrahydropyrimido[4,5-b]quinoline-2,4,6(1H,3H,5H)-trione (294198-02-0)

Conditions	Yield
With N-methyl-2-oxopyrrolidin-1-ium dihydrogen phosphate at 80℃; for 0.666667h;	98%
With rhodium(III) chloride hydrate In water at 40℃; for 0.05h; Concentration; Temperature; Time; Reagent/catalyst; Solvent; Sonication; Green chemistry;	96%
With Fe3O4 nanoparticles supported on cellulose In water for 2h; Reflux; Green chemistry;	96%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + dimedone (126-81-8) + meta-hydroxybenzaldehyde (100-83-4) → 1,3,8,8-tetramethyl-5-(3-hydroxyphenyl)-5,8,9,10-tetrahydropyrimido[4,5-b]quinoline-2,4,6(1H,3H,7H)-trione (1353998-42-1)

Conditions	Yield
With zirconium hydrogen sulfate In neat (no solvent) at 80℃; for 1h;	98%
With toluene-4-sulfonic acid In water at 90℃; for 3h;	86%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-methyl-(3-carboxyl-3-oxoprop-1-enyl)benzene (17451-22-8) → 1,2,3,4,5,8-hexahydro-1,3-dimethyl-5-(4-methylphenyl)-2,4-dioxopyrido[2,3-d]pyrimidine-7-carboxylic acid (1172581-68-8)

Conditions	Yield
With cadmium oxide nanoparticles In ethanol at 20℃; for 0.166667h; Michael Addition;	98%
With zinc(II) oxide at 70℃; for 2h;	94%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + (E)-4-(4-bromophenyl)-4-oxobut-2-enoic acid (20972-38-7) → 7-(4-bromophenyl)-1,3-dimethyl-2,4-dioxo-1,2,3,4,5,6-hexahydropyrido[2,3-d]pyrimidine-5-carboxylic acid

Conditions	Yield
In acetic acid for 0.75h; Reflux;	98%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + (E) 4-(4-fluorophenyl)-4-oxo-2-butenoic acid (35504-85-9) → 7-(4-fluorophenyl)-1,3-dimethyl-2,4-dioxo-1,2,3,4,5,6-hexahydropyrido[2,3-d]pyrimidine-5-carboxylic acid

Conditions	Yield
In acetic acid for 0.75h; Reflux;	98%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + phenyl isothiocyanate (103-72-0) + 4-bromo-benzaldehyde (1122-91-4) → 5-(4-bromophenyl)-1,3-dimethyl-6-phenyl-7-thioxo-5,6,7,8-tetrahydropyrimido[4,5-d]pyrimidine-2,4(1H,3H)-dione (1544273-97-3)

Conditions	Yield
With {3-[(6,8-disulfonaphthalen-2-yl)amino]propyl}(ethoxy)silanebis(olate) functionalized silica coated magnetic iron oxide nanoparticles In water for 1.25h; Reflux; Green chemistry;	98%
With MIL-53(Fe) metal-organic framework In neat (no solvent) at 110℃; Green chemistry;	97%
With PEG-bound sulfonic acid In water Reflux; Green chemistry;	78%
With toluene-4-sulfonic acid In water Reflux; Green chemistry; regioselective reaction;	71%

6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-nitrobenzaldehdye (555-16-8) + phenyl isothiocyanate (103-72-0) → 1,3-dimethyl-5-(4-nitrophenyl)-6-phenyl-7-thioxo-5,6,7,8-tetrahydropyrimido[4,5-d]pyrimidine-2,4(1H,3H)-dione (1544274-00-1)

Conditions	Yield
With {3-[(6,8-disulfonaphthalen-2-yl)amino]propyl}(ethoxy)silanebis(olate) functionalized silica coated magnetic iron oxide nanoparticles In water for 1h; Catalytic behavior; Reagent/catalyst; Solvent; Temperature; Reflux; Green chemistry;	98%
With MIL-53(Fe) metal-organic framework In neat (no solvent) at 110℃; Green chemistry;	98%
With PEG-bound sulfonic acid In water Reflux; Green chemistry;	90%
With toluene-4-sulfonic acid In water Reflux; Green chemistry; regioselective reaction;	67%

4-hydroxy[1]benzopyran-2-one (1076-38-6) + 6-Amino-1,3-dimethylbarbituric acid (6642-31-5) + 4-bromo-benzaldehyde (1122-91-4) → 6‐amino‐5‐((4‐bromophenyl)(4‐hydroxy‐2‐oxo‐2H‐chromen‐3‐yl)methyl)‐1,3‐dimethylpyrimidine‐2,4(1H,3H)‐dione (1450627-40-3)

Conditions	Yield
With zirconium hydrogen sulfate In neat (no solvent) at 80℃; for 1h;	98%
With 2-(3-phenylthioureido)ethylprolinamide In water for 0.25h; Reflux;	95%
With phosphotungstic acid In ethanol; water at 20℃; for 0.3h;	89%
Stage #1: 4-hydroxy[1]benzopyran-2-one; 4-bromo-benzaldehyde With 1-(1-benzylpiperidin-4-yl)-3-(2-(piperidin-1-yl)ethyl)thiourea In water for 0.25h; Reflux; Stage #2: 6-Amino-1,3-dimethylbarbituric acid In water for 4h;	86%
With Fe3O4(at)TiO2 Nanocomposite In water at 20℃; for 2.5h; Green chemistry;

Upstream product

• 96-31-1 N,N'-Dimethylurea 
• 105-34-0 methyl 2-cyanoacetate 
• 16044-79-4 5,7-Dimethylpyrimido<4.5-e>-1,2,4-triazinedione, isofervenulin 
• 105-56-6 ethyl 2-cyanoacetate 
• 77-78-1 dimethyl sulfate 
• 74-88-4 methyl iodide 
• 6972-77-6 N-cyanoacetyl-N'-methyl-urea 
• 54660-80-9 6-amino-1,3-dimethyl-5-formyluracil 
• 89-25-8 edaravone 
• 873-83-6 4-Amino-2,6-dihydroxypyrimidine 
• 108-24-7 acetic anhydride 
• 372-09-8 cyanoacetic acid 
• 99747-54-3 1,3-dimethyl-2,4-dioxo-6-<(triphenylphosphoranylidene)amino>-1,2,3,4-tetrahydropyrimidine 
• 98-86-2 acetophenone 

Downstream Products

• 122707-25-9 6-amino-1,3-dimethyl-5-phenylazouracilate 
• 32970-32-4 5-acetyl-6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione 
• 58-55-9 theophylline 
• 7597-60-6 1,3-dimethyl-4-amino-5-(formylamino)uracil 
• 769-42-6 1,3-dimethylbarbituric acid 
• 7150-04-1 6-amino-5-bromo-1,3-dimethylpyrimidine-2,4(1H,3H)-dione 
• 6632-68-4 6-amino-1,3-dimethyl-5-nitroso-1H-pyrimidine-2,4-dione 
• 62374-43-0 5,7-dimethyl-3-(tri-O-benzoyl-β-D-ribofuranosylamino)-7H-isothiazolo[3,4-d]pyrimidine-4,6-dione 
• 93599-95-2 1,3-dimethyl-5-(4-methoxycinnamoyl)-6-aminouracil 
• 143505-05-9 5,6-Dihydro-1,3-dimethyl-7-phenyl-6-(3-phenyl-1-(3,4,5-trimethoxyphenyl)-3-oxoprop-1-yl)-5-(3,4,5-trimethoxyphenyl)-pyrido<2,3-d>pyrimidin-2,4-(1H,3H)-dion 
• 96996-67-7 1,3,7-Trimethyl-5-(3-nitro-phenyl)-2,4-dioxo-1,2,3,4,5,8-hexahydro-pyrido[2,3-d]pyrimidine-6-carboxylic acid ethyl ester 
• 95834-26-7 6-Amino-5-[1-(4-hydroxy-phenyl)-2-nitro-ethyl]-1,3-dimethyl-1H-pyrimidine-2,4-dione 
• 142168-89-6 N-methyl 2-methylamino-5-nitro-3-pyridine carboxamide 
• 96996-68-8 2-(N-benzyl-N-methylamino)ethyl 5-(2-chlorophenyl)-1,2,3,4,5,8-hexahydro-1,3,7-trimethyl-2,4-dioxopyrido<2,3-d>pyrimidine-6-carboxylate 

Relevant articles and documents

Spectrophotometric investigation of 5-nitroso-6-aminouracil and its methyl derivative in methanol by selective complexation with bivalent metal ions

6-Amino-5-nitrosouracils are synthesized by the condensation reaction of urea or N,N′-dimethyl urea, cyanoacetic acid and acetic anhydride followed by nitrosation reaction with sodium nitrite. The synthesized compounds are characterized by various spectroscopic techniques like FTIR, NMR, single crystal XRD, and UV–vis absorption spectroscopy. From a single-crystal X-ray crystallography study of DANU, it is found that the compound is crystalline with one water molecule. The binding properties of both compounds with various metal ions are studied using UV–vis spectroscopy, where ANU shows a colour change from colourless to yellow colour-forming complex with cobalt metal ion. While DANU shows a colour change from colourless to dark yellow forming complex with copper and nickel cation, respectively. These compounds showed the job's plots with Cu2+, Ni2+, and Co2+ in various stoichiometric ratios to form the respective metal complex. The association/binding constant (Ka) values are calculated by plotting Benesi–Hilderbrand plots of ANU with Co2+ ion and is found to be 9.524 × 102. Whereas, DANU with Cu2+, Ni2+ are found to be 3.956 × 103, 2.041 × 103, respectively. These cations may be used in metal ions complexation for the respective ligand. The LOD values for ANU-Co2+, DANU-Cu2+ & DANU-Ni2+ are obtained as 33.9428 μM, 93.8082 μM and 48.396 μM, respectively, whereas the LOQ values are found as 102.857 μM, 284.2675 μM and 146.653 μM, respectively.

Pyrimidopteridine N-Oxide Organic Photoredox Catalysts: Characterization, Application and Non-Covalent Interaction in Solid State

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Structural and conformational studies on carboxamides of 5,6-diaminouracils-precursors of biologically active xanthine derivatives

8-Arylethynylxanthine derivatives are potent, selective adenosine A2A receptor antagonists, which represent (potential) therapeutics for Parkinson's disease, Alzheimer's dementia, and the immunotherapy of cancer. 6-Amino-5-amidouracil derivatives are important precursors for the synthesis of such xanthines. We noticed an unexpected duplication of NMR signals in many of these uracil derivatives. Here, we present a detailed analytical study of structurally diverse 6-amino-5-carboxamidouracils employing dynamic and two-dimensional NMR spectroscopy, density functional theory calculations, and X-ray analysis to explain the unexpected properties of these valuable drug intermediates.