Total Synthesis of FR901464, an Antitumor Agent that Regulates the Transcription of Oncogenes and Tumor Suppressor Genes

FR901464 is a potent anticancer agent that regulates the transcription of oncogenes and tumor suppressor genes. A convergent enantioselective synthesis of FR901464 was accomplished in 13 linear steps. Central to the synthetic approach was the diene-ene cross olefin metathesis reaction to generate the C6-C7 olefin, without the use of protecting groups, as the final coupling. Additional key reactions include a Zr/Ag-promoted alkynylation to set the C4 stereocenter, a mild and chemoselective Red-Al reduction, a stereoselective Mislow-Evans-type [2,3]-sigmatropic rearrangement to install the C5 stereocenter, a Carreira asymmetric alkynylation to generate the C4' stereocenter, and a highly efficient ring-closing metathesis-allylic oxidation sequence to form an unsaturated lactone.