Toward a Formal Synthesis of Laureatin: Unexpected Rearrangements Involving Cyclic Ether Nucleophiles

摘要: Laureatin, a metabolite of the red algae Laurencia nipponica, has shown potent activity as mosquito larvicide. The two previously published syntheses laureatin involved an initial preparation 8-membered cyclic ether, followed by formation oxetane ring. Our strategy was reverse, i.e., to utilize framework construct larger During this work, attempted N-bromosuccinimide (NBS)-mediated cyclization alcohol 17, prepared from readily accessible 2-methyleneoxetane 12, yielded epoxytetrahydrofuran 19 rather than expected core. Further derivatization trans fused bis-tetrahydrofuran 32. synthesis and 32, well structural stereochemical elucidation studies, are described.