Methanol → HCID 178418456, compound

To a stirred suspension of 7-chloro-2,3-dihydro-10-hydroxypyridazino[4,5-b]quinoline-1,4-dione (1.00 g, 3.8 mM) in water (40 mL) was added choline hydroxide (0.86 mL, 3.8 mM, 50 weight per cent, aqueous solution). Toluene (250 mL) was added to the resulting solution and the mixture was concentrated using a rotary evaporator. The residue was diluted with toluene (250 mL) and the resulting mixture concentrated again to provide a yellow residue. This residue was stirred for 60 hr with methanol (25 mL) and the resulting suspension was filtered to separate the solids which were washed with methanol (3 mL) and then dried under a stream of nitrogen for 1 hr. Further drying of the solids in vacuo at 100° C. for 20 hr provided (0.76 g, 55%) of the title compound as a yellow powder, mp 267°-269° C.

1. concentrationthe mixture was concentrated
2. customa rotary evaporator
3. additionThe residue was diluted with toluene (250 mL)
4. concentrationthe resulting mixture concentrated again
5. customto provide a yellow residue
6. filtrationthe resulting suspension was filtered
7. customto separate the solids which
8. washwere washed with methanol (3 mL)
9. customdried under a stream of nitrogen for 1 hr
10. customFurther drying of the solids in vacuo at 100° C. for 20 hr

ORD record

ord-4061f90aaff7419f9113b9addf8ac370

Source dataset

uspto-grants-1998_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05733910