Ring-opening reactions of sucrose epoxides: Synthesis of 4′-derivatives of sucrose

✍ Scribed by Riaz Khan; Michael R. Jenner; Harold Lindseth; Khizar S. Mufti; Gita Patel

• Book ID: 102992357
• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 584 KB
• Volume: 162
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(87)80215-x

✦ Synopsis

The 2,1'-0-isopropylidene derivative (1) of 3-O-acetyl-4,6-O-isopropylidenecu-~glucopyranosyl 6-O-acetyl-3,4-anhydro-fl-D-lyxo-hexulofuranoside and 2,3,4tri-O-acetyl-6-O-trityl-cY-D-glucopyranosyl 3,4-anhydro-1,6-di-0-trityl-@-D-lyxohexulofuranoside have been synthesised and 1 has been converted into 2,3,4,6tetra-0-acetyl-a-D-glucopyranosyl 1,6-di-0-acetyl-3,4-anhydro-/3-D-lyxo-hexulofuranoside (2). The S,2 reactions of 2 with azide and chloride nucleophiles gave the corresponding 2,3,4,6-tetra-0-acetyl-cY-D-glucopyranosyl 1,3.6-tri-O-acetyl-4 azido-4-deoxy-/3-D-fructofuranoside (6) and 2,3,4,6-tetra-O-acetyl-cr-D-glucopyranosyl 1,3,6-tri-O-acetyl-4-chloro-4-deoxy-P_D-fnoside (8)) respectively. The azide 6 was catalytically hydrogenated and the resulting amine was isolated as 2,3,4,6-tetra-0-acetyl-cw-D-glucopyranosyl 4-acetamido-1,3,6-tri-Oacetyl-4-deoxy-P_D-fructofuranoside. Treatment of 5 with hydrogen bromide in glacial acetic acid followed by conventional acetylation gave 2,3,4,6-tetra-o-acetylcu-D-glucopyranosyl 1,3,6-tri-O-acetyl-4-bromo-4-deoxy-P-D-f~cto~ranoside. Similar S,2 reactions with 2,3,4,6-tetra-0-acetyl-a-D-glucopyranosyl 1,6-di-Oacetyl-3,4-anhydro-@-r&o-hexulofuranoside (12) resulted in a number of 4'derivatives of ar-D-glucopyranosyl /3-D-sorbofuranoside. The regiospecific nucleophilic substitution at position 4' in 2 and 12 has been explained on the basis of steric and polar factors.