Construction of the Azacyclic Core of Tabernaemontanine-Related Alkaloids <i>via</i> Tandem Reformatsky–Aza-Claisen Rearrangement

A divergent synthetic methodology for a tabernaemontanine-related alkaloid was developed. The synthetic route features practical improvements in the Pictet–Spengler cyclization for the tetrahydro-β-carboline intermediate and an unprecedented tandem Reformatsky–aza-Claisen rearrangement to create the core carbon skeleton and stereochemistries of tabernaemontanine-related alkaloids

Construction of the Azacyclic Core of Tabernaemontanine-Related Alkaloids <i>via</i> Tandem Reformatsky–Aza-Claisen Rearrangement

A divergent synthetic methodology for a tabernaemontanine-related alkaloid was developed. The synthetic route features practical improvements in the Pictet–Spengler cyclization for the tetrahydro-β-carboline intermediate and an unprecedented tandem Reformatsky–aza-Claisen rearrangement to create the core carbon skeleton and stereochemistries of tabernaemontanine-related alkaloids

Stereoselective Synthesis of 1,4,5-Tri-<i>cis</i>-guaiane Sesquiterpene: First Total Synthesis of (−)-Dendroside C Aglycon

The first total synthesis of (−)-dendroside C aglycon, consisting of a 1,4,5-tri-<i>cis</i>-guaiane skeleton, from a versatile hydroazulene intermediate has been accomplished. The key features of the syntheses include the stereoselective preparation of the unusual <i>cis</i>-hydroazulene core via a sequence of a unique Dieckmann condensation of the bicyclic lactone system, which was concisely prepared by the tandem conjugate addition and intramolecular allylic alkylation of a butenolide precursor, and construction of the characteristic tricyclic skeleton by a carbene-mediated cyclopropanation

Asymmetric Total Synthesis of (+)-Intricenyne via an Endocyclization Route to Oxocane Skeleton

The first total synthesis of (+)-intricenyne consisting of an oxocane skeleton was achieved via an extremely selective endocyclization strategy. The key features of the synthesis include a regio- and diastereoselective epoxide opening reaction, concise elaboration of oxocane cores via abnormally selective endocyclization ether ring formation, and versatile incorporation of the labile functional groups

Asymmetric Total Synthesis of (+)-(3<i>E</i>)‑Pinnatifidenyne via Abnormally Regioselective Pd(0)-Catalyzed Endocyclization

The asymmetric total synthesis of the marine natural product (+)-(3<i>E</i>)-pinnatifidenyne was accomplished. The key features of the synthesis involve the construction of an eight-membered cyclic ether by the abnormally regioselective Pd(0)-catalyzed cyclization, the installation of a double bond in the oxocene skeleton by sequential <i>in situ</i> deconjugative isomerization, and the efficient introduction of the crucial chloride mediated by the substrate-controlled diastereoselective reduction