[2+2]Cycloaddition of chlorosulfonyl isocyanate to 3-O-vinyl ethers de
rived from D-glucose and D-glucuronolactone proceeded with an excellen
t stereoselectivity to provide azetidin-2-ones with (R) configuration
at C-4'. Intramolecular N-alkylation afforded 1-oxabicyclic-beta-lacta
ms having six- or seven-membered ring fused to the four-membered one.
(C) 1997 Elsevier Science Ltd.