Hydrochloric Acid → 2-(4-methoxybenzylthio)-pentanoyl-(L)-homophenylalanine

Participants

Reaction Steps

Combine 2-(4-methoxybenzylthio)-pentanoyl-(L)-homophenylalanine methyl ester (3.50 g, 8.15 mmol) and methanol (30 mL)and tetrahydrofuran (30 (mL). Cool in an ice bath. Add an aqueous 2M lithium hydroxide solution (8.2 mL, 16.4 mmol). After 18 hours, adjust the pH to about 6 using an aqueous 10% hydrochloric acid solution and evaporate in vacuo to give a residue. Partition the residue between dichloromethane and water, adjust the pH of the aqueous layer to about 1 using an aqueous 10% hydrochloric acid solution. Separate the layers, extract the aqueous layer repeatedly with ethyl acetate. Combine the organic layers, dry over Na2SO4, filter, and evaporate in vacuo to give a residue. Chromatograph the residue on silica gel eluting with 95% 1/1 hexane/ethyl acetate/5% acetic acid to give the title compound.

Provenance & Evidence