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Indian Journal of Chemistry -Section B (IJC-B) >
IJC-B Vol.48B [2009] >
IJC-B Vol.48B(06) [June 2009] >
| Title: | Synthesis of blocked trisaccharide analogue related to the repeating unit of the O-antigen form E. coli : 025 |
| Authors: | Srivastava, Jayant
Khare, Anakshi
Khare, Naveen K |
| Keywords: | Carbohydrates
synthesis
regioselective
stereoselective
glycosylation
trisaccharide |
| Issue Date: | Jun-2009 |
| Publisher: | CSIR |
| Abstract: | Methyl 2-O-benzoyl-4, 6-O-benzylidene-O- -d-glucopyranoside 1 was condensed with rhamnose-1-thio donor 2 in the presence of NIS/TMSOTf to yield the disaccharide methyl 2,3,4-tri-O-acetyl-O--l-rhamnopyranosyl-(1-3)-2-O-benzoyl-4,6-O-benzylidene-O--d-glucopyranoside 3. Acidic hydrolysis of compound 3 followed by tritylation, deacylation and benzylation yields the disaccharide methyl 2,3,4-tri-O-benzyl-O--l-rhamnopyranosyl-(1-3)-2,4-di-O-benzyl-6-O-trityl-O--d-glucopyranoside 6. Compound 6 on detritylation yields the acceptor methyl 2,3,4-tri-O-benzyl-O--l-rhamnopyranosyl-(1-3)-2,4-di-O-benzyl-O--d-glucopyranoside 7 which on condensation with known glucose-1-thio donorstyle 8 in the presence of NIS/TMSOTf yields the linear protected trisaccharide methyl 2,3,4,6-tetra-O-acetyl-O-β-d-glucopyranosyl-(1-6)-2,3,4-tri-O-benzyl-O--l-rhamnopyranosyl-(1-3)-2,4-di-O-benzyl-O--d-glucopyranoside 9. |
| Page(s): | 848-852 |
| ISSN: | 0376-4699 |
| Source: | IJC-B Vol.48B(06) [June 2009]
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