1,1'-Carbonyldiimidazole → HCID 66628638, compound

Participants

Reaction Steps

Carbonyldiimidazole (352 mg, 1.6 equiv.) was added to a solution of 2-{(3R,6R)-3-(2,3-dihydro-1H-inden-2-yl)-6-[(1S)-1-methylpropyl]-2,5-dioxo-1-piperazinyl}-N-(2-hydroxyphenyl)-2-(2-methyl-1,3-oxazol-4-yl)acetamide (11.8 g pre-dried in vacuo over P4O10 for 24 hours) in dichloromethane (20 mL) and the solution was left at room temperature for 16 hr. The mixture was evaporated and the residue dissolved in acetone (20 ml) and water (20 ml) added, followed by addition of 2NHCl (2 ml) and the mixture left at room temperature for 4.5 hr. This was extracted with ethylacetate (2×30 ml) and the combined organic phase dried via a hydrophobic frit and evaporated. The residue was taken up in ethylacetate (30 ml) washed with 2NHCl (2×10 ml) and then extracted with saturated sodium bicarbonate solution (2×15 ml). The combined aqueous phase was acidifed with 2NHCl and extracted with ethylacetate (2×20 ml) and the combined organic phase washed with brine dried via a hydrophobic frit and evaporated to give {(3R,6R)-3-(2,3-dihydro-1H-inden-2-yl)-6-[(1S)-1-methylpropyl]-2,5-dioxo-1-piperazinyl}(2-methyl-1,3-oxazol-4-yl)acetic acid (0,355 mg, 73%) as a white solid.

Provenance & Evidence