Total synthesis of trioxilins 11,12-threo-(8,11,12)-A3 through type B3 trioxilins

The total synthesis of trioxilins 11,12-threo-TrXB₃ has been extended to the corresponding trioxilins of the (8,11,12)-A₃ type. The synthesis involves the allylic rearrangement of a protected TrXB₃ derivative with a free 10-hydroxyl group under the Mitsunobu reaction conditions as the key step.