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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 44608Generated: October 24, 2026

Triethylamine → 8-(Cyclopentylamino)-N-hydroxy-N,1-dimethyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxamide

https://huagongshe.com/en/reaction/44608

Reaction equation

Participants

RoleNameHCIDCharge
ReactantTriethylamineHCID 8471—
ReactantOxalyl chlorideHCID 65578—
ReactantN-methylhydroxylamine hydrochlorideHCID 77906—
ReactantPotassium 8-(cyclopentylamino)-1-methyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxylateHCID 45140959—
CatalystDimethylformamideHCID 6228—
SolventDichloromethaneHCID 6344—
Product8-(Cyclopentylamino)-N-hydroxy-N,1-dimethyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxamideHCID 45139427199.8%

Reaction Steps

To a suspension of 400 mg (1.14 mmol) of potassium 8-(cyclopentylamino)-1-methyl-4,5-dihydro-1H-pyrazolo[4,3-h]quinazoline-3-carboxylate in 80 mL of dichloromethane and a few drops of dimethylformamide 0.11 mL (0.13 mmol) of oxalyl chloride were added at 0° C. The mixture was stirred at room temperature for 6 hours and then evaporated, redissolved in anhydrous dichloromethane and dropped into a solution of 344 mg (2.28 mmol) of N-methylhydroxylamine hydrochloride and 0.33 mL of triethylamine in 20 mL of the same solvent, cooled to 0° C. After 4 hours the mixture was washed with a saturated solution of sodium hydrogenocarbonate, dried over sodium sulfate and evaporated to dryness. The residue was triturated with diethylether and filtered to give 780 mg (60% yield) of the title compound.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS08541429B2
Source datasetuspto-grants-2013_09
ORD IDord-0d1bedce630f49159deaf5a937a38ece
Source noteuspto-grants-2013_09