Simple and Stereoselective Syntheses of Nucleoside Analogues with a Benzo[c]furan Glycone Moiety
摘要:
A series of d4T analogues have been synthesised in which the 2',3'didehydro-2',3'-dideoxyribose moiety is replaced by a benzo[c]furan core. A simple strategy has been developed to access a range of compounds for biological screening. In addition, a stereoselective approach has been achieved with view to permit more detailed studies.
Both enantiomers of 3-benzoyloxymethylisobenzofuranone have been obtained in good yield in six steps from phthalaldehyde using a D-xylose derivative as a chiral protecting group. The two chiral heterocycles are gamma-hydroxymethyl-alpha,beta-butenolide analogues having a benzene ring in positions 2 and 3. The key step was the dihydroxylation using both OsO4 and AD-mix developed by Sharpless. The asymmetric dihydroxylation using AD-mix required a double diastereoselectivity and gave excellent diastereoisomeric excess. (C) 2003 Elsevier Science Ltd. All rights reserved.