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A short stereoselective synthesis of the fusarium toxin equisetin, an N-met
hylserine-derived acyl tetramic acid and potent inhibitor of HIV-1 integras
e enzyme, is described using as the key step a stereoselective lithium perc
hlorate mediated intramolecular Diels-Alder reaction of a fully conjugated
E,E,E-triene with a trisubstituted gamma,delta -unsaturated beta -ketothioe
ster.