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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Dienyne ring-closing metathesis approach for the construction of taxosteroids
María J Aldegunde1, Rebeca García-Fandiño, Luis Castedo
1Departamento de Química Orgánica e Unidade Asociada ó C.S.I.C. Facultade de Química, Universidade de Santiago, 15782 Santiago de Compostela, Spain.
Abstract:
A cascade dienyne ring-closing metathesis approach has been applied to the synthesis of the tetracyclic carbon framework of a new class of hybrid compounds-the taxosteroids-possessing carbon frameworks incorporating moieties characteristic of both taxanes (such as AB rings) and steroids (i.e., CD system and side chain). This tandem cyclization is highly stereoselective, allowing the one-step formation of the bicyclo[5.3.1]undecene system characteristic of taxol. In this work we describe the scope and limitations of such cyclizations.
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