Reaction #53391

Reaction equation

80

4-(2,4-Dimethoxyphenyl)butylamidino-3,5-diamino-6-chloropyrazine carboxamide hydrochloride

→

81

Yield 58.3%

4-(2,4-Dihydroxyphenyl)butylamidino-3,5-diamino-6-chloropyrazine carboxamide hydrochloride

Yield 58.3%

Solvents

HBr

Conditions

Workup

1. 1
   Temperaturecooled
2. 2
   OtherThe solvent was removed at reduced pressure
3. 3
   Otherthe material was purified by column chromatography (silica gel, 4:1:0.1 chloroform/ethanol/concentrated ammonium hydroxide)
4. 4
   OtherThe fractions with product were collected
5. 5
   Otherthe solvent was removed under reduced pressure
6. 6
   workup.ADDITIONThe residue was treated with 3% HCl
7. 7
   Washwashed with water (2×5 mL)
8. 8
   Otherdried

Procedure

A vigorously stirred solution of 80 (290 mg, 0.63mmol) in 48% HBr (20 mL) was refluxed for 4 h and then cooled. The solvent was removed at reduced pressure and the material was purified by column chromatography (silica gel, 4:1:0.1 chloroform/ethanol/concentrated ammonium hydroxide). The fractions with product were collected and the solvent was removed under reduced pressure. The residue was treated with 3% HCl, washed with water (2×5 mL) and dried to provide 81 (79 mg, 32%) as a yellow solid. 1H NMR (300 MHz, DMSO-d6) δ1.54 (s, 4H), 2.43 (br s, 2H), 3.31 (br s, 2H), 6.12 (d, 1H), 6.32 (s, 1H), 6.78 (d, 1H), 8.86 (br s, 1H), 8.99 (br s, 1H), 9.28 (s, 1H), 10.56 (s, 1H). APCI MS m/z 394 [C16H20ClN7O3+H]+.

Source