4-Methylmorpholine → HCID 54293522, compound

Participants

Reaction Conditions

Reaction Steps

10.0 Parts N-t-butoxycarbonyl-L-tyrosylglycylglycine and 2.4 parts N-methylmorpholine are dissolved in 125 parts dimethylformamide and cooled to -15° C. Then 3.8 parts isobutyl chloroformate is added dropwise over a 30 minute period while maintaining the temperature at -15° C. Then, a solution of 12.7 parts L-tryptophyl-L-methionine benzyl ester hydrochloride in 50 parts dimethylformamide is slowly added at -15° C. and the mixture is stirred at this temperature for 30 minutes. The cooling apparatus is removed and the mixture is stirred at ambient temperature for an additional 2 hours. The product is isolated by diluting the reaction mixture with 10 volumes water and extracting with ethyl acetate. The ethyl acetate extracts are combined, dried over anhydrous sodium sulfate and stripped to dryness under reduced pressure. Purification of the residue by low pressure column chromatography affords N-t-butoxycarbonyl-L-tyrosylglycylglycyl-L-tryptophyl-L-methionine benzyl ester.

Provenance & Evidence