1,3-diazinane-2,4,5,6-tetrone;hydrate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of N-(4-methoxyphenyl)benzene-1,2-diamine (9.0 g) in ethanol (150 ml) was added a solution of alloxan monohydrate (6.7 g) in water (150 ml) and the mixture was stirred for 30 minutes. The precipitate was filtered off and recrystallised from glacial acetic acid giving the title compound mp 236°-238° C. The precipitate was filtered off recrystallised from glacial acetic acid giving the title compound mp 236°-238° C.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (1.6 g., 0.01 mole) was dissolved in 40 ml. of ethanol by heating. 5-Bromoindole (1.96 g., 0.01 mole) was added and heating near reflux continued for 15 minutes. Tlc did not indicate that reaction had occured. 1N Hydrochloric acid (10 ml.) was then added while maintaining the reaction near reflux. After 10 minutes, the reaction was concentrated to wet solids. Trituration of these wet solids with water gave the title product [3.17 g., m.p. >250° C.; Rf 0.45 (1:1 ethyl acetate:hexane/5% acetic acid); Rf 0.3 (1:5 ethyl acetate:hexane/5% acetic acid)]. heating near reflux Tlc did not indicate that reaction while maintaining the reaction near reflux After 10 minutes the reaction was concentrated to wet solids

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (1.6 g., 0.01 mole) was dissolved in 40 ml. of ethanol by heating. 5-Bromoindole (1.96 g., 0.01 mole) was added and heating near reflux continued for 15 minutes. Tlc did not indicate that reaction had occured. 1N Hydrochloric acid (10 ml.) was then added while maintaining the reaction near reflux. After 10 minutes, the reaction was concentrated to wet solids. Trituration of these wet solids with water gave the title product [3.17 g., m.p. >250° C.; Rf 0.45 (1:1 ethyl acetate:hexane/5% acetic acid); Rf 0.3 (1:5 ethyl acetate:hexane/5% acetic acid)]. heating near reflux Tlc did not indicate that reaction while maintaining the reaction near reflux After 10 minutes the reaction was concentrated to wet solids

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-Phenylpyrrole (1.4 g., 0.01 mole), alloxan hydrate (1.6 g., 0.01 mole) and 50 ml. of ethanol were combined and refluxed for 15 minutes. No reaction was noted by tlc. 1N Hydrochloric acid (10 ml., 0.01 mole) was added and the acidified mixture refluxed for 15 minutes. Incomplete reaction was noted by tlc. A second portion of alloxan hydrate (1.6 g., 0.01 mole) was added and the mixture refluxed another 15 minutes, cooled and evaporated to dryness. Trituration of the residue with water gave title product [2.3 g.; m/e 285; m.p. 232°-234° C. (dec); Rf 0.3 (1:1 ethyl acetate:hexane)]. refluxed for 15 minutes the acidified mixture refluxed for 15 minutes Incomplete reaction the mixture refluxed another 15 minutes cooled evaporated to dryness

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (3.2 g., 0.02 mole) was dissolved in 50 ml. of ethanol by warming. 1-Methylpyrrole (1.6 g., 0.02 mole) was added and the mixture warmed for 5 minutes on a steam bath, while perfusing with hydrogen chloride. After standing at room temperature for 0.5 hour, the reaction mixture was evaporated to dryness and the residue triturated with water to yield title product as a solid [2.9 g.; m/e 223; Rf 0.5 (1:1 ethyl acetate:hexane/5% acetic acid)]. the mixture warmed for 5 minutes on a steam bath the reaction mixture was evaporated to dryness the residue triturated with water

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 10 g of 4,5-dichloro-o-phenylenediamine, 9 g of alloxan hydrate, 1.5 g of boric acid and 250 ml of glacial acetic acid was stirred overnight at room temperature to obtain a brown-black solution which was filtered. The yellow-buff crystalline solid was well washed with water to obtain 15.9 g of 7,8-dichloro-alloxazine melting at >370° C. A solution of 2 g of 7,8-dichloro-alloxazine in 10 ml of concentrated sulfuric acid was slowly heated to 240° C. and held there for 10 minutes. The mixture was cooled and poured onto ice and the mixture was made alkaline with sodium hydroxide addition. The mixture was extracted several times with ether to obtain 0.73 g of 2-amino-6,7-dichloro-quinoxaline as an orange crystalline solid melting at 220° C. to obtain a brown-black solution which was filtered The yellow-buff crystalline solid was well washed with water

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (1.6 g., 0.01 mole) was dissolved in 40 ml. of ethanol by heating. 5-Bromoindole (1.96 g., 0.01 mole) was added and heating near reflux continued for 15 minutes. Tlc did not indicate that reaction had occured. 1 N Hydrochloric acid (10 ml.) was then added while maintaining the reaction near reflux. After 10 minutes, the reaction was concentrated to wet solids. Trituration of these wet solids with water gave the title product [3.17 g., m.p. >250° C.; Rf 0.45 (1:1 ethyl acetate:hexane/5% acetic acid); Rf 0.3 (1:5 ethyl acetate:hexane/5% acetic acid)]. heating near reflux Tlc did not indicate that reaction while maintaining the reaction near reflux After 10 minutes the reaction was concentrated to wet solids

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (1.6 g., 0.01 mole) 1-methylindole (1.3 g., 0.01 mole) and ethanol (50 ml.) was combined and the mixture refluxed for 0.5 hour, then concentrated to half-volume, diluted with water and the resulting product recovered by filtration [2.7 g., Rf 0.5 (1:1 ethyl acetate:hexane/5% acetic acid)]. the mixture refluxed for 0.5 hour concentrated to half-volume diluted with water the resulting product recovered by filtration [2.7 g., Rf 0.5 (1:1 ethyl acetate:hexane/5% acetic acid)]

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-Phenylpyrrole (1.4 g., 0.01 mole), alloxan hydrate (1.6 g., 0.01 mole) and 50 ml. of ethanol were combined and refluxed for 15 minutes. No reaction was noted by tlc. 1 N Hydrochloric acid (10 ml., 0.01 mole) was added and the acidified mixture refluxed for 15 minutes. Incomplete reaction was noted by tlc. A second portion of alloxan hydrate (1.6 g., 0.01 mole) was added and the mixture refluxed another 15 minutes, cooled and evaporated to dryness. Trituration of the residue with water gave title product [2.3 g.; m/e 285; m.p. 232°-234° C. (dec); Rf 0.3 (1:1 ethyl acetate:hexane)]. refluxed for 15 minutes the acidified mixture refluxed for 15 minutes Incomplete reaction the mixture refluxed another 15 minutes cooled evaporated to dryness

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (3.2 g., 0.02 mole) was dissolved in 50 ml. of ethanol by warming. 1-Methylpyrrole (1.6 g., 0.02 mole) was added and the mixture warmed for 5 minutes on a steam bath, while perfusing with hydrogen chloride. After standing at room temperature for 0.5 hour, the reaction mixture was evaporated to dryness and the residue triturated with water to yield title product as a solid [2.9 g.; m/e 223; Rf 0.5 (1:1 ethyl acetate:hexane/5% acetic acid)]. the mixture warmed for 5 minutes on a steam bath the reaction mixture was evaporated to dryness the residue triturated with water

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 10 g of 4,5-dichloro-o-phenylenediamine, 9 g of alloxan hydrate, 1.5 g of boric acid and 250 ml of glacial acetic acid was stirred overnight at room temperature to obtain a brown-black solution which was filtered. The yellow-buff crystalline solid was well washed with water to obtain 15.9 g of 7,8-dichloro-alloxazine melting at >370° C. A solution of 2 g of 7,8-dichloro-alloxazine in 10 ml of concentrated sulfuric acid was slowly heated to 240° C. and held there for 10 minutes. The mixture was cooled and poured onto ice and the mixture was made alkaline with sodium hydroxide addition. The mixture was extracted several times with ether to obtain 0.73 g of 2-amino-6,7-dichloro-quinoxaline as an orange crystalline solid melting at 220° C. to obtain a brown-black solution which was filtered The yellow-buff crystalline solid was well washed with water

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Alloxan hydrate (1.6 g., 0.01 mole) was dissolved in 40 ml. of ethanol by heating. 5-Bromoindole (1.96 g., 0.01 mole) was added and heating near reflux continued for 15 minutes. Tlc did not indicate that reaction had occured. 1 N Hydrochloric acid (10 ml.) was then added while maintaining the reaction near reflux. After 10 minutes, the reaction was concentrated to wet solids. Trituration of these wet solids with water gave the title product [3.17 g., m.p. >250° C.; Rf 0.45 (1:1 ethyl acetate:hexane/5% acetic acid); Rf 0.3 (1:5 ethyl acetate:hexane/5% acetic acid)]. heating near reflux Tlc did not indicate that reaction while maintaining the reaction near reflux After 10 minutes the reaction was concentrated to wet solids