Triphenylphosphine → (3S,8S)-3-[4-(2-cyclopentyl-ethoxy)-phenyl]-7-((S)-1-phenyl-propyl)-2,3,6,7,8,9-hexahydro-[1,4]dioxino[2,3-g]isoquinoline-8-carboxylic acid

Participants

Reaction Steps

(S)-3-(4-Hydroxy-phenyl)-7-((S)-1-phenyl-propyl)-2,3,6,7,8,9-hexahydro-[1,4]dioxino[2,3-g]isoquinoline-8-carboxylic acid methyl ester (20 mg) was dissolved in DCM and cyclopentane-ethanol (5 eq.), triphenyl phosphine (5 eq.) and DIAD (4.5 eq.) added. The reaction mixture stirred at room temperature and was directly purified over silica (hexanes to 9:1 hexanes EtOAc to 7:3 hexanes EtOAc). This ester was hydrolyzed according to General Procedure AB to give (3S,8S)-3-[4-(2-cyclopentyl-ethoxy)-phenyl]-7-((S)-1-phenyl-propyl)-2,3,6,7,8,9-hexahydro-[1,4]dioxino[2,3-g]isoquinoline-8-carboxylic acid. This acid was coupled with (S)-2-amino-3-[4-(2,3-dimethyl-pyridin-4-yloxy)-phenyl]-propionic acid methyl ester di hydrochloride according to General Procedure L to give (S)-2-{[(3S,8S)-3-[4-(2-cyclopentyl-ethoxy)-phenyl]-7-((S)-1-phenyl-propyl)-2,3,6,7,8,9-hexahydro-[1,4]dioxino[2,3-g]isoquinoline-8-carbonyl]-amino}-3-[4-(2,3-dimethyl-pyridin-4-yloxy)-phenyl]-propionic acid methyl ester. This ester was hydrolyzed according to General Procedure B to give the title compound (5 mg). LCMS (m/z): 811.

Provenance & Evidence