An approach to the synthesis of (–)-lipstatin by Wittig reaction and Lewis acid-promoted [2 + 2] cycloaddition
Abstract
The β-lactone moiety of (–)-lipstatin 1, a potent inhibitor of pancreatic lipase, is prepared via a Lewis acid-promoted [2 + 2] cycloaddition between hexyltrimethylsilyl ketene 3 and the (Z,Z)-dienic aldehyde 4, obtained from hexanal by two stereoselective Wittig reactions.