Ethylmorpholine → N-(N'-(Boc)-glutaminyl-serinyl)leucine benzyl ester

Participants

Reaction Conditions

Reaction Steps

N-(serinyl)leucine benzyl ester hydrochloride (350 g) (prepared as described in Step 1), HOBt (157.7 g) and N-Boc-L-glutamine (262.5 g) were slurried in DMF (2.5 L) and the mixture was cooled to 0° C. N-Ethylmorpholine (245.5 g) and EDC.HCl (214 g) were added and the mixture was aged at 0° C. for 2.5 hours. Water (14.7 L) was added over 20 minutes and the white slurry aged at 0° C. for 1 hour. The product collected by filtration and washed with water (3.2 L). The cake was dried in the fume-hood overnight. The isolated N-BOC-Gln-Ser-Leu-OBn, which contained DMF and HOBt, was combined with a second batch of identical size, and swished in water (12 L) at 20° C. for 1 hour. The product was collected by filtration, washed with water (2.5 L) and air-dried in a fume-hood over the weekend. The batch was dried in vacuo, at 42° C., with a nitrogen bleed.

Provenance & Evidence