2D NMR spectroscopy analysis of polysaccharide, COSY spectrum (A), HSQC spectrum (B), TOCSY spectrum (C), NOESY spectrum (D), HMBC spectrum (E).

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... anomeric carbons of residues C, D and E were identified from cross peaks in the HSQC spectrum at δ C 99.74, 100.81 and 96.92 ppm respectively. Other hydrogen and carbon signals of these residues were also assigned by the same analogy from the COSY (Fig. 4A) and HSQC spectra (Fig. 4B). The peak assignment data are presented in Table 2. However, the carbon signals of C-3-C-6 of sugar residue D were not clearly detected in the 13 C NMR spectrum, which was probably due to the low contents and overlapping by signals of residues A and ...

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... anomeric carbons of residues C, D and E were identified from cross peaks in the HSQC spectrum at δ C 99.74, 100.81 and 96.92 ppm respectively. Other hydrogen and carbon signals of these residues were also assigned by the same analogy from the COSY (Fig. 4A) and HSQC spectra (Fig. 4B). The peak assignment data are presented in Table 2. However, the carbon signals of C-3-C-6 of sugar residue D were not clearly detected in the 13 C NMR spectrum, which was probably due to the low contents and overlapping by signals of residues A and ...

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... type of substitution in the residues was determined by comparing the chemical shifts of the carbon atoms in the residues with those in the corresponding unsubstituted sugars. The HSQC spectrum (Fig. 4B) revealed down-field shifts for carbon atoms C-4 of residue A, C-4 and C-6 of residue C. Proton chemical shift values of residue D determined from TOCSY (Fig. 4C) experiment which they were similar with values of residue C and may be non-reducing terminal residue of C. In addition we found terminal (unsubstituted) residues B and E ...

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... substitution in the residues was determined by comparing the chemical shifts of the carbon atoms in the residues with those in the corresponding unsubstituted sugars. The HSQC spectrum (Fig. 4B) revealed down-field shifts for carbon atoms C-4 of residue A, C-4 and C-6 of residue C. Proton chemical shift values of residue D determined from TOCSY (Fig. 4C) experiment which they were similar with values of residue C and may be non-reducing terminal residue of C. In addition we found terminal (unsubstituted) residues B and E which probably were reducing terminals of the main and side chains. Considering methylation analysis data and abovementioned NMR results residues A and C assigned to ...

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... (Fig. 4D) and HMBC (Fig. 4E) spectra were employed for determination of the sequences of these residues. In HMBC spectrum were observed a strong correlation between H-1 (δ H 5.39)/C-4 (δ C 77.93) of residue A itself which confirmed 1,4-linkage of α-D-Glcp (A) in main chain. The correlation H-6 (δ H 4.04)/C-1 (δ C 99.74) of residue C itself which ...

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... (Fig. 4D) and HMBC (Fig. 4E) spectra were employed for determination of the sequences of these residues. In HMBC spectrum were observed a strong correlation between H-1 (δ H 5.39)/C-4 (δ C 77.93) of residue A itself which confirmed 1,4-linkage of α-D-Glcp (A) in main chain. The correlation H-6 (δ H 4.04)/C-1 (δ C 99.74) of residue C itself which assigned to be ...