Total Synthesis of Ouabain, a Potent Cardiac Glycoside

描述（由申请人提供）：

DESCRIPTION (provided by applicant): Cardiac glycoside natural products have been used as medicinal agents for hundreds of years. Ouabain, an important member of this class, has found utility in modern medicine for the treatment of congestive heart failure, a disease that millions of people suffer from every year. Given ouabain's biological importance, it has become a target of interest to the chemical and biological communities. A successful synthetic route to ouabain will assist in the preparation of analogs and could, therefore, allow for the discovery of more powerful medicines. An original and concise approach for the total synthesis of ouabain is presented herein. This asymmetric synthesis incorporates a pi-allyl Heck reaction to build the C/D ring system and a convergent intermolecular Diels-Alder reaction to construct the full steroidal skeleton of the natural product. The development of a catalytic enantioselective variant of the pi-allyl Heck reaction for the synthesis of quaternary carbon stereocenters is also proposed.