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Updated: Jun 2, 2026

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
On the reactivity of 23-methoxycarbonyl furospirostanes
Mariana Macías-Alonso1, Marcos Flores-Álamo, Martin A Iglesias-Arteaga
1Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 Mexico, DF, Mexico.
Abstract:
Brønsted and Lewis acid-catalysed reactions of the 23-methoxycarbonyl furospirostanic side chain are described. While bromination, deuteration and BF(3)·Et(2)O/AcOH treatment involve regioselective F-ring opening with exclusive participation of Δ(22)-furostenic intermediates, BF(3)·Et(2)O/Ac(2)O treatment leads to irreversible E- or F-ring cleavage.
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