(R)-(+)-1-Phenylethyl isocyanate → (S)-2-{[(3R,8S)-3-[4-(3,4-Dichloro-benzyloxy)-phenyl]-7-((R)-1-phenyl-ethylcarbamoyl)-2,3,6,7,8,9-hexahydro-[1,4]dioxino[2,3-g]isoquinoline-8-carbonyl]-amino}-3-[4-(2,3-dimethyl-pyridin-4-yl)-phenyl]-propionic acid

Participants

Reaction Steps

(S)-2-({(3R,8S)-3-[4-(3,4-Dichloro-benzyloxy)-phenyl]-2,3,6,7,8,9-hexahydro-[1,4]dioxino[2,3-g]isoquinoline-8-carbonyl}-amino)-3-[4-(2,3-dimethyl-pyridin-4-yl)-phenyl]-propionic acid methyl ester (35 mg) was dissolved in 2 mL DCM and ((R)-1-isocyanato-ethyl)-benzene (5 equiv) added and reaction stirred at room temperature for 2 hours. The reaction mixture was directly purified over silica (hexanes to 1:1 hexanes EtOAc to 1:1 hexanes EtOAc+2% MeOH). The resulting compound was hydrolyzed according to General Procedures B to give the title compound (28 mg). LCMS (m/z): 886.

Provenance & Evidence