Hydrochloric Acid → 7-(2-Bromothiophen-3-yl)-5-(1-hydroxyguanidin-3-yl)imino-4-methyl-5,6,7,8-tetrahydroquinoline hydrochloride

Temperature

90 °C

To a mixture of 7-(2-bromothiophen-3-yl)-4-methyl-5,6,7,8-tetrahydroquinolin-5-one (0.245 g) and 1-amino-3-hydroxyguanidine p-toluenesulfonate (262 mg) were added ethanol (3 ml) and concentrated hydrochloric acid (0.1 ml), and the mixture was stirred at 90° C. for 2 hours. Under reduced pressure, the solvent was evaporated, and to the residue was added 0.2N sodium hydroxide solution (20 ml). The mixture was extracted with a mixture of ethyl acetate (20 ml) and tetrahydrofuran (20 ml). The organic layer was washed with 0.2N sodium hydroxide solution (20 ml) and water, to which was added 2N hydrochloric acid (0.8 ml). The mixture was concentrated, and to the residue was added ethanol (3 ml). The mixture was stirred at 90° C. for 3 hours and cooled, and precipitated crystals were filtered, washed with ethanol and dried to give 7-(2-bromothiophen-3-yl)-5-(1-hydroxyguanidin-3-yl)imino-4-methyl-5,6,7,8-tetrahydroquinoline hydrochloride (Compound 125) (0.215 g) as pale yellow crystals.

1. customUnder reduced pressure, the solvent was evaporated
2. additionto the residue was added 0.2N sodium hydroxide solution (20 ml)
3. extractionThe mixture was extracted with a mixture of ethyl acetate (20 ml) and tetrahydrofuran (20 ml)
4. washThe organic layer was washed with 0.2N sodium hydroxide solution (20 ml) and water, to which
5. additionwas added 2N hydrochloric acid (0.8 ml)
6. concentrationThe mixture was concentrated
7. additionto the residue was added ethanol (3 ml)
8. stirringThe mixture was stirred at 90° C. for 3 hours
9. temperaturecooled
10. customprecipitated crystals
11. filtrationwere filtered
12. washwashed with ethanol
13. customdried

ORD record

ord-d70f6adba62f44408a2c4543e32349a2

Source dataset

uspto-grants-2002_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06350749B1