A multicomponent coupling strategy suitable for the synthesis of the triene component of the oxazolomycin antibiotics

Concise and versatile routes suitable for the synthesis of three geometric isomers of an analogue of the left hand triene sub-unit of oxazolomycin are reported. A strategy based upon a key Heck reaction was unsuccessful, and this was traced to a combination of steric encumbrance and electronic deactivation of the alkene substrate. An alternative Stille coupling strategy, however, proved to be both versatile and high yielding, and is potentially applicable to the synthesis of analogues with variation both in the side-chain geometry and in the identity of the terminal aromatic or heteroaromatic residue.