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Updated: May 22, 2026

Functionalized Spirocyclic Heterocycle Synthesis and Cytotoxicity Assay
Published on: February 9, 2021
Synthesis, characterization and biological evaluation of some novel 17-isoxazoles in the estrone series
Dóra Kovács1, Zalán Kádár, Gergő Mótyán
1Department of Organic Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary.
Abstract:
Regioselective 1,3-dipolar cycloadditions of different aryl nitrile oxides to mestranol were carried out to furnish novel steroidal 17α-isoxazoles in good to excellent yields. Copper(I) was found to be an efficient catalyst, accelerating the intermolecular ring-closures and leading exclusively to 3,5-disubstituted isoxazoles. The yields of the cycloadducts, however, were influenced by the substituents on the aromatic moiety of the 1,3-dipoles. Moreover, dehydration of the primary products resulted in the corresponding Δ(16,17)exo-heterocyclic derivatives. All the synthesized compounds were subjected to in vitro pharmacological studies of their antiproliferative effects relative to three human malignant cell lines (HeLa, MCF7 and A2780).
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