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ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Published monthly
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Synthesis and reactions of uronic acid derivatives. XII. Synthesis of methyl[methyl 2-0-(2,3,4,6-tetra-0-methyl-β-D-glucopyranosyl)-3,4-di-0-methyl-α-D-galactopyranosid]uronate, a fully methylated β-D-1 → 2-linked pseudoaldobiuronic acid
J. Hirsch, P. Kováč, V. Kováčik, and V. Mihálov
Institute of Chemistry. Slovak Academy of Sciences.
809 33 Bratislava
Abstract: A good yield of crystalline pseudoaldobiouronic acid derivative /// was obtained by
allowing to react 2,3,4,6-tetra-O-acetyl-l-bromo-l-deoxy-α-D-glucopyranose with
methyl(methyl 3,4-0-isopropylidene-a-D-galactopyranosid)uronate under the conditions of modified Königs—Knorr synthesis of glycosides. The alcoholic hydroxyl groups
in /// were regenerated by selective deisopropylidenation and subsequent deacetylation
giving the crystalline methyl ester methyl glycoside V Methylation of V with methyl
iodide and silver oxide in N,N-dimethylformamide, which gave the crystalline title
derivative VII as the main product, was accompanied by a β-elimination reaction
forming the olefinic disaccharide X. Olefin X was also synthesized and obtained
crystalline by directed β-elimination reaction of /// followed by methylation of the
deacetylated, crystalline olefin IX. The structures of VII. X and their synthetic
precursors were confirmed by mass spectrometry.
Full paper in Portable Document Format: 305a674.pdf
Chemical Papers 30 (5) 674–681 (1976)
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