Ammonia → HCID 59349652, compound

Participants

Reaction Steps

335.0 mg (0.824 mmol) of the compound from Example 41A are introduced into 10 ml of ethyl acetate, and 167.1 mg (0.537 mmol) of 1,1′-carbonyldiimidazole are added. The suspension is then stirred at room temperature overnight. Since a clear solution is not produced, 2 ml of DMF are added and the mixture is stirred at room temperature for a further two hours. Complete conversion is then established by TLC check. The volatile components are removed in a rotary evaporator, and the residue is taken up in 4 ml of DMF. Then 2.293 ml of ammonia (28% by weight solution in water, 16.5 mmol) and 10.1 mg of 4-N,N-dimethylaminopyridine are added. The reaction mixture is heated at 100° C. in a closed vessel for thirty minutes. After cooling, the solvent is removed under reduced pressure, and the residue is purified by preparative HPLC (eluent: acetonitrile/water with 0.1% formic acid, gradient 20:80→95:5). The product fractions are concentrated and the residue is taken up in a little dichloromethane, and diisopropyl ether is added until the solution is cloudy. The precipitated solid is isolated and dried in vacuo. 207 mg (59% of theory) of the title compound are obtained.

Provenance & Evidence