Triethylamine → (2-Methoxyethoxy)methyl-2-{[1-({[(3s)-1-(2-tert.butoxy-2-oxoethyl)-2-oxo-2,3,4,5-tetrahydro-1h-1-benzazepin-3-yl]amino}carbonyl)cyclopentyl]methyl}-4-(isopropylamino)-4-oxobutyric acid

Participants

Reaction Steps

300 mg 2-{[1-({[(3S)-1-(2-tert.butoxy-2-oxoethyl)-2-oxo-2,3,4,5-tetrahydro-1H-1-benzazepin-3-yl]amino}-carbonyl)cyclopentyl]methyl}-4-(isopropylamino)-4-oxobutyric acid (for preparation see Example 12) was dissolved in 5 ml dichloromethane. 33 mg DMAP, 74 μl methoxyethoxymethyl chloride and 90 μl triethylamine were added to this receiving solution. The reaction mixture was stirred overnight, then diluted with 5 ml dichloromethane and the organic phase was washed in succession once each with 3 ml dilute aqueous KHSO4 solution and saturated aqueous common salt solution. The organic phase was dried over magnesium sulfate, the solvent was largely evaporated at reduced pressure and the remaining residue was chromatographed on silica gel (mobile phase: EA/cyclohexane 2:1 v/v). Drying the product fractions in an oil pump vacuum yielded 191 g of the title compound, MS: [M+H]+: 646; m/z: 590, 540, 484, 425.

Provenance & Evidence