Dichloromethane → 2-(3-tert-butoxycarbonylmethyl-2,4-dioxo-1-pyrimidinyl)acetyl-L-valyl-N-[(1S)-2-(2-benzoxazolyl)-1-isopropyl-2-oxoethyl]-L-prolinamide

Participants

Reaction Steps

To methylene chloride (30 ml) containing 2-(3-tert-butoxy-carbonylmethyl-2,4-dioxo-1-pyrimidinyl)acetyl-L-valyl-N-[(1S)-2-(2-benzoxazolyl)-1-isopropyl-2-hydroxyethyl]-L-prolinamide (1.5 g) obtained in Example 9 are added t-butyl alcohol (0.16 g) and a Dess-Martin reagent (1.9 g), and the mixture is stirred at room temperature for one hour. The reaction solution is poured into a saturated aqueous sodium thiosulfate solution, and the mixture is extracted with ethyl acetate. The extract is washed successively with a saturated aqueous sodium thiosulfate solution, a saturated aqueous sodium hydrogen carbonate solution, and a saturated brine, and dried over anhydrous magnesium sulfate. The solvent is removed by evaporation under reduced pressure to give the desired 2-(3-tert-butoxycarbonylmethyl-2,4-dioxo-1-pyrimidinyl)acetyl-L-valyl-N-[(1S)-2-(2-benzoxazolyl)-1-isopropyl-2-oxoethyl]-L-prolinamide (1.2 g) as powders.

Provenance & Evidence