Rapid Access to 2,2-Disubstituted Indolines via Dearomative Indolic-Claisen Rearrangement: Concise, Enantioselective Total Synthesis of (+)-Hinckdentine A.

The construction of 2,2-disubstituted indolines has long presented a synthetic challenge without any general solutions. Herein, we report a robust protocol for the dearomative Meerwein-Eschenmoser-Claisen rearrangement of 3-indolyl alcohols that provides efficient access to 2-substituted and 2,2-disubstituted indolines. These versatile subunits are useful for natural product synthesis and medicinal chemistry.

Tetrodotoxin: History, Biology, and Synthesis.

This review provides a comprehensive coverage of the history, biology and chemistry of tetrodotoxin (TTX). It traces the origin of this remarkable molecule all the way back to the ancient Chinese medicine records. The discovery of biological activity, isolation, and a brief overview of structure elucidation are summarized.

Chemoenzymatic Synthesis of Advanced Intermediates for Formal Total Syntheses of Tetrodotoxin.

Advanced intermediates for the syntheses of tetrodotoxin reported by the groups of Fukuyama, Alonso, and Sato were prepared. Key steps include the toluene dioxygenase mediated dihydroxylation of either iodobenzene or benzyl acetate. The resulting diene diols were transformed into Fukuyama's intermediate in six steps, into Alonso's intermediate in nine steps, and into Sato's intermediate in ten steps.