Water → (r)-3-((s)-2-(4,4-Dimethyl-3-(4-(3-(2-methylphenyl)ureido)-3-hydroxybenzyl)-2,5-dioxoimidazolidin-1-yl)-2-(cyclopropylmethyl)acetylamino)-3-methylpropionic acid

Participants

Reaction Conditions

Reaction Steps

211 μL of boron tribromide were added under argon to a solution of 100 mg (0.169 mmol) of the compound of Example 1 in 20 mL of absolute dichloromethane at −78° C. and the reaction mixture was allowed to warm to 0° C. with ice cooling. After 30 minutes at 0° C., water was cautiously added. The phases were separated and the organic phase was dried over sodium sulfate. After filtration, removal of the solvent in vacuo, chromatographic purification by preparative HPLC and freeze drying of the product fractions, 35 mg (36%) of the title compound were obtained.

Provenance & Evidence