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Updated: Aug 1, 2025

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
Synthesis of Fused Tricyclic Amines Bearing Tetrasubstituted Carbons Using an
Takeo Sakai1, Tomoki Furuhata1, Kota Hosoe1
1Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya 468-8503, Japan.
Abstract:
A new cascade reaction sequence that involves alkylation, cyclization, isomerization, and 3-aza-Cope rearrangement was discovered. The stereogenic centers of the starting piperidines were transferred to the bicyclic enamine products, and a range of electron-withdrawing groups on the alkyne moieties, from ketones to amides, were tolerated under the reaction conditions. The bicyclic enamines underwent trifluoroacetic acid (TFA)-mediated cyclization to form tricyclic amines bearing tetrasubstituted carbons.
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