1,2-Dichloroethane → (S)-2-({(3S,8S)-7-(2,5-Dimethyl-oxazole-4-carbonyl)-3-[4-(4-trifluoromethyl-cyclohexylmethoxy)-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

Participants

Reaction Steps

(3S,8S)-8-{(S)-1-Carboxy-2-[4-(2,3-dimethyl-pyridin-4-yl)-phenyl]-ethyl-carbamoyl}-3-(4-hydroxy-phenyl)-2,3,8,9-tetrahydro-6H-[1,4]dioxino[2,3-g]isoquinoline-7-carboxylic acid tert-butyl ester was coupled with (4-trifluoromethyl-cyclohexyl)-methanol according to the General Procedure K. The resulting product was converted to (S)-2-({(3S,8S)-7-(2,5-dimethyl-oxazole-4-carbonyl)-3-[4-(4-trifluoromethyl-cyclohexyl-methoxy)-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 according to General Procedure C, then the residue was suspended in DCM. TEA (3 eq.) added and the mixture was concentrated. In a separate vial, EDC (3 eq.) and 2,5-dimethyl-oxazole-4-carboxylic acid (6 eq.) were dissolved in DCM and stirred for 40 minutes. This solution was added to the above mixture and stirred for 16 hours. The reaction mixture was directly purified over silica (hexanes; 1:1 hexanes/EtOAc; 1:1 hexanes EtOAc+1% MeOH). This ester was hydrolyzed according to General Procedure B to give the title compound. LCMS (m/z): 868.

Provenance & Evidence