STUDIES RELATED TO THE SYNTHESIS OF PEDERIN .2. SYNTHESIS OF PEDEROL DIBENZOATE AND BENZOYLPEDAMIDE

Syntheses of the ring B fragments (+)-pederol dibenzoate (2) and (±)-benzoylpedamide (3) of the insect toxin pederin (1) are described. An intramolecular directed aldol condensation was used to construct the tetrahydropyran ring in (+)-pederol dibenzoate (2). Better stereocontrol in the synthesis of (±)-benzoylpedamide (3) was achieved in which the stereochemistry at C-11 was introduced by a conjugate addition of TMSCN to the dihydropyranone (31). The synthesis of (±)-pederin from (±)-(3) and the ring A. fragment (±)-benzoylselenopederic acid (38) is described. © 1990.