Synthesis of the C-1 sidechain of the squalestatins and zaragozic acid A

Abstract

A synthesis of a protected C-1 side chain precursor ( 2) of the anti-cholesteremic agents the squalestatins and zaragozic acid A has been achieved in 9 steps from 1,4-butanediol. The key transformations involve a one pot oxidation/α-methylenation sequence to provide the α,β-unsaturated aldehyde 4 and subsequent asymmetric aldol reaction to introduce the C-4′ and C-5′ stereocentres.