Highly concise and general asymmetric syntheses of biologically important natural (–)-8,4′-oxyneolignans [(–)-virolin, (–)-surinamensin, (–)-raphidecursinol B, and (–)-polysphorin] are reported. The key step in the synthesis is the Evan’s syn-aldol reaction to achieve the adducts with the desired stereochemistry. The four biologically important plant metabolites were synthesized using two common intermediates.
Key words
asymmetric synthesis - chiral auxiliary - aldol reaction - natural products - oxyneolignans