Synthesis of trans-syn-trans fused bis-pyrans via endo-selective cyclizations of cyclic sulfates

Article abstract of DOI:10.1016/S0040-4039(99)00214-2

Acid-catalyzed cyclization of hydroxy-cyclic sulfates occurs with endo- regioselectivity affording bispyran products from substrates in which the nucleophilic hydroxyl and electrophilic cyclic sulfate groups are 1,2-trans- substituted on a cyclic pyran template. This methodology is demonstrated in an enantioselective synthesis of the trans-syn-trans fused AB cyclic ether rings of the brevetoxin natural products.