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Updated: Aug 20, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Unexpected reactivity difference between iodo-alkene moieties of steroids possessing remote lactame or cycloalkane
Sándor Kunsági-Máté1, Rita Skoda-Földes, László Szepes
1Faculty of Sciences, Department of General and Physical Chemistry, University of Pécs, H-7624 Pécs, Ifjúság 6, Hungary. kunsagi@ttk.pte.hu
Abstract:
The steroidal ring A possessing cyclohexane vs. delta-valerolactame structures shows a 'long-range effect' on the reactivity of the 'iodovinyl' functionality of the ring D. The strikingly different reactivity of 17-iodo-16-ene functionality of steroids is explained on the basis of the redistribution of kinetic energy of the system. The vibrational energy localized on the 'iodovinyl' moiety proved to be determinant in the CI bond-breaking process. The appearance of the lactame moiety in the ring A supports a redistribution of the kinetic energy on the molecule. As a result, a drastic decrease in C-I bond stretching has been obtained, which could diminish the C-I bond breaking, and therefore, results in decreased reactivity of the iodovinyl moiety in agreement with experimental findings.
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