Dimethyl Sulfide → HPro-DTrp-Phe-DTrp-Leu-MetNH2

Participants

Reaction Conditions

Reaction Steps

BocPro-DTrp-Phe-DTrp-Leu-MetNH2 (2.45 mmole.) was added to a solution of trifluoroacetic acid (18 ml.), dimethylsulfide (20 ml.) and ethanedithiol (1.8 ml.) with cooling to 0° C. The mixture was allowed to warm to room temperature, stirred for one hour, and stripped of volatiles. The residue was washed with hexane, then with ether, then purified by reverse phase high pressure liquid chromatography on octadecylsilated silica gel using methanol-water (75:25) containing ammonium acetate (0.2%) as eluant. Conversion of the product to the phosphate salt by ion exchange and lyophilization afforded HPro-DTrp-Phe-DTrp-Leu-MetNH2, which was isolated as the amorphous white solid phosphate (1:1) salt hydrate (2:7) in 62% yield (1.63 g.).

Provenance & Evidence