Synthesis of a derivative of a-D-Glcp(1→2)-D-Galf suitable for further glycosylation and of a-D-Glcp(1→2)-D-Gal, a disaccharide fragment obtained from varianose

Article abstract of DOI:10.3762/bjoc.8.241

The presence of galactofuranoyl units in infectious microorganisms has prompted the study of the metabolic pathways involved in their incorporation in glycans. Although much progress has been made with respect to the biosynthesis of β-D-Galf-containing glycoconjugates, the mechanisms by which α-D-Galf units are incorporated remain unclear. Penicillium varians is a non-pathogenic fungus that produces varianose, a polysaccharide containing both a- and β-D-Galf units, which can be used as a model for biosynthetic studies on α-D-Galf incorporation. Synthetic oligosaccharide fragments related to varianose are useful as potential substrates or standards for characterization of the a-galactofuranosyl transferases. In this paper we report a straightforward procedure for the synthesis of a-D-Glcp(1→2)-D-Gal (1) and the use of this compound to monitor the natural disaccharide released from varianose by mild acid degradation. The synthesis, performed by the glycosylaldonolactone approach, involved a glucosylgalactofuranose derivative, suitable for the synthesis of higher oligosaccharides with an internal D-Galf.

Full text of DOI:10.3762/bjoc.8.241

Supporting Information
for
Synthesis of a derivative of -D-Glcp(1→2)-D-Galf suitable
for further glycosylation and of -D-Glcp(1→2)-D-Gal, a
disaccharide fragment obtained from varianose
1
1
1,2
1
Carla Marino *, Carlos Lima , Karina Mariño and Rosa M. de Lederkremer
1
Address: CIHIDECAR-CONICET-UBA, Departamento de Química Orgánica,
Facultad de Ciencias Exactas y Naturales, UBA, Buenos Aires (1428), Argentina and
2
Laboratorio de Glicómica Funcional y Molecular, Instituto de Biología y Medicina
Experimental (IBYME), CONICET, Buenos Aires (1428), Argentina
Email: Carla Marino* - cmarino@qo.fcen.uba.ar
*
Corresponding author
NMR spectra of compounds 1, 5, 7 and 8
Table of Contents
1
H NMR spectrum of compound 5 ....................................................................................................... S2
1
1
1
1
1
1
1
3
C NMR spectrum of compound 5 ...................................................................................................... S3
H NMR spectrum of compound 7 ....................................................................................................... S4
3
C NMR spectrum of compound 7 ...................................................................................................... S5
H NMR spectrum of compound 8 ....................................................................................................... S6
3
C NMR spectrum of compound 8 ...................................................................................................... S7
H NMR spectrum of compound 1 ....................................................................................................... S8
3
C NMR spectrum of compound 1 ...................................................................................................... S9
S1

10.0 9.5
9.0
8.5
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7.5
7.0
6.5
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5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
ppm
1
Figure S1: H NMR of compound 5.
S2

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Figure S2: C NMR of compound 5.
S3

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1
Figure S3: H NMR of compound 7.
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Figure S4: C NMR of compound 7.
S5

9.0
8.5
8.0
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Figure S5: H NMR of compound 8.
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Figure S6: C NMR of compound 8.
S7

7.0
6.5
6.0
5.5
5.0
4.5
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3.5
3.0
2.5
2.0
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1
Figure S7: H NMR of compound 1.
S8

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Figure S8: C NMR of compound 1.
S9