Synthesis of new camptothecin analogues with the E-lactone ring replaced by α,β-cyclohexenone

Article abstract of DOI:10.1002/ejoc.200600298

The total synthesis of racemic camptothecin analogues 12a and 12b, in which the E-lactone ring has been replaced by an α,β-cyclohexenone ring and the ethyl and hydroxy substituents have been retained, was achieved by first preparing the ABCD fragments 31a