4-Methylmorpholine → 2-Chloro-N-[1-[(3-methyl-1,2,4-oxadiazol-5-yl)methyl]-2-oxo-1,2,3,4-tetrahydroquinolin-3-yl]-6H-thieno[2,3-b]pyrrole-5-carboxamide

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Reaction Steps

N-Methylmorpholine (118 μL, 1.07 mmol) then ethyl chloroformate (103 μL, 1.07 mmol) were added to N-[1-(carboxymethyl)-2-oxo-1,2,3,4-tetrahydroquinolin-3-yl]-2-chloro-6H-thieno[2,3-b]pyrrole-5-carboxamide (Example 2; 431 mg, 1.07 mmol) in anhydrous THF (10 mL) at 0° C. After 20 minutes N′-hydroxyethanimidamide (119 mg, 1.61 mmol) was added and the reaction stirred at ambient temperature for 3 days then at reflux for 5 hours. After evaporation to dryness the residue was suspended in 1,4-dioxane and refluxed for 18 hours. On cooling the mixture was diluted with EtOAc (100 mL) and washed with H2O (25 mL). The aqueous was extracted with DCM (3×50 mL) and the combined organics dried (MgSO4), filtered and evaporated. The residue was purified by column chromatography (DCM to DCM:MeOH (9:1)) to give a yellow solid which was dissolved in MeOH:DCM (1:4) (100 mL) and shaken with macroporous silicate-carbonate scavenger resin (300 mg). Filtration then evaporation gave the title compound (291 mg, 61%) as an off-white solid.

Provenance & Evidence