Regioselective sulfonylation of 6,1′,6′-tri-O-tritylsucrose through dibutylstannylation: Synthesis of 4′-O-sulfonyl derivatives of sucrose

Abstract

3-O-Mesyl-1,6-di-O-trityl-β-D-fructofuranosyl-(2→1)-6-O-trityl- α-D-glucopyranoside (3) was synthesized via stannylation of 6,1′,6′-tri-O-tritylsucrose with dibutyltin oxide in benzene, followed by treatment of the crude product with methanesulfonyl chloride in the presence of triethylamine in dichloromethane at 0°C. A similar treatment of the tri-tritylsucrose in toluene, instead of benzene, yielded 4-O-mesyl-1,6-di-O-trityl-β-D-fructofuranosyl-(2→1)-6-O-trityl- α-D-glucopyranoside (4) as the major product. The X-ray crystal structure of the corresponding acetyl derivative, 3-O-acetyl-4-O-mesyl-1,6-di-O-trityl-β-D-fructofuranosyl-(2→1)-2, 3,4-tri-O-acetyl-6-O-trityl-α-D-glucopyranoside (5), confirms the position and stereochemistry of the methanesulfonyl group at C-4 of the fructofuranosyl ring. © 2002 Elsevier Science Ltd. All rights reserved.