N- -L-aspartate

Fig. 19.—Circular Dichroism of 2-Acetamido-l-N-(L-aspart-4-oyl)-2-deoxy-/3-D-gIucosyl-amine.

Subsequently, this mode of synthesis was extended to the preparation of similar derivatives.22-29 For example, the groups of Tsukamoto,25 Hough,26 and Yoshimura28 reported the synthesis of 2-acetamido-N-(L-aspart-l-oyl)-2-deoxy-/ -D-glycopyranosylamine (13) by coupling 8 with 4-benzyl N-(benzyloxycarbonyl)-L-aspartate30 (12) in the presence of DCC, followed by O-deacetylation, de-esterification, and hydrogeno-... 

Glycopeptides containing a 2-acetamido-N-(L-aspart-4-oyl)-2-deoxy-/ -D-glucopyranosylamine residue (11) may be synthesized either by direct addition of the carbohydrate residue to the peptide chain, or by elongation of the peptide chain from 11 in the direction of the carboxylic, or the amino, terminal. 

N-(L-aspart-4-oyl)- 2,3,4,6-tetra-0-aeetyl-N-[l-benzyl N-(benzyloxycarbonyl)-L-aspart-4- 224-227 + 10.4 h2o 38... 

N-[L-aspart-1 -oyl-(L-phenylalanyl-L-phenylalanyl-L-tryptophanyl-L-lysine)-4-oyl]-N-(L-aspart-1 -oyl)-... 

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