pubmed:abstractText |
Triterpene glycopeptides, derivatives of glycyrrhizic acid, were synthesized with the use of tert-butyl esters of L-amino acids. The condensation of glycoside with esters was carried out with N-hydroxysuccinimide--N,N-dicyclohexylcarbodiimide or N-hydroxybenzotriazol--N,N'-dicyclohexylcarbodiimide in the presence of a base (triethylamine, N-methyl- or N-ethylmorpholine). The protection groups were removed with the use of trifluoroacetic acid.
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