Original scientific paper

Glucuronic Esters. VI. Syntheses of Fully Protected 1-0-Acylaminoacyl-D-Glucuronic Acids by the Imidazole Promoted Active Ester and Drydohexylcarbodi-imide Methods

G. Roglić ; Tracer Laboratory, Institute »Ruder Boskovic«, 41000 Zagreb, Croatia, Yugoslavia
D. Keglević ; Tracer Laboratory, Institute »Ruder Boskovic«, 41000 Zagreb, Croatia, Yugoslavia

Abstract

Fully protected o-glucuronic estern linked at C-1 to the
carboxyl group of N-acyl-DL and L-amino acids were synthesized
by two methods involving direct participation of imidazole in the
ester linkage formation: (a) accelerated active ester method and
(b) imidazole promoted DCC condensation. The synthesis was
performed with fully-methylated and -benzylated C-1 free o-glucuronic
acid as the sugar component and with pentachlorophenyl
esters of benzyloxycarbonyl- and tert-butyloxycarbonyl- amino
acids in method (a), or with benzyloxycarbonyl- and acetylamino
acids in method (b). Fully methylated o-glucuronic acid I,
prepared from o-glucurono-6,3-lactone and dimethyl sulphate, was
used as the starting material for the synthesis of methylated sugar
component II; GLC and chemical studies indicate the furanose
structure for I. The corresponding glucuronic esters were obtained
as anomeric mixtures which were resolved and characterized.
Conditions for the cleavage of the amino acid protecting group
were studied and the fully methylated 1-0-glycyl-~-n-glucuronate
was obtained as the monooxalate salt in crystalline form.

Keywords

Hrčak ID:

197269

URI

https://hrcak.srce.hr/197269

Publication date:

15.7.1972.

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