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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1624810Generated: October 30, 2026

Hydrochloric Acid → HCID 178493675, compound

https://huagongshe.com/reaction/1624810

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantEthanolHCID 702—
ReactantSodium HydroxideHCID 14798—
ReactantHCID 178469983HCID 178469983—
SolventWaterHCID 962—
ProductHCID 178493675HCID 17849367532%

Reaction Steps

A mixture of ethyl 1-{3-fluoro-4-[5-methoxy-4-oxo-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-1(4H)-yl]phenyl}-5-hydroxy-1H-pyrazole-4-carboxylate (1.41 g, 2.73 mmol), 4 M NaOH (40 mL), and EtOH (40 mL) was refluxed for 4 h. After cooling to room temperature, conc. HCl (20 mL) was added slowly. The mixture was stirred for 30 min at room temperature and then refluxed for 1 h. After cooling to room temperature, the reaction mixture was poured into water and extracted with AcOEt. The extract was washed with brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography eluting with AcOEt/THF (2/1) and recrystallized from THF/MeOH to give the title compound (387 mg, 32% yield) as a pale yellow solid: mp 221-229° C.; 1H NMR (300 MHz, DMSO-d6): δ ppm 3.78 (3H, s), 5.57 (1H, d, J=1.5 Hz), 6.99 (1H, d, J=1.9 Hz), 7.14 (1H, t, J=9.0 Hz), 7.31-7.51 (6H, m), 7.64-7.68 (1H, m), 7.79-7.84 (2H, m), 8.52 (1H, d, J=1.9 Hz), 12.17 (1H, brs). LC-MS (ESI) m/z 445 [M+H]+.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS08778944B2
Source datasetuspto-grants-2014_07
ORD IDord-c30e6cebcae04b4fa9d40084a1d1f958
Source noteuspto-grants-2014_07