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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
The use of squaric acid as a scaffold for cofacial phenyl rings
Rajeev S Muthyala1, Gopal Subramaniam, Louis Todaro
1Department of Chemistry and Biochemistry, Queens College and the Graduate Center of the City University of New York, Flushing, New York 11367-1597, USA. rajeev_muthyala@qc.edu
Abstract:
[structure: see text] To examine the possibility of using squaric acid as a scaffold for organizing phenyl rings in a cofacial orientation, we undertook an investigation of the conformational preferences of secondary and tertiary N-phenylsquaramides. In secondary squaramides, the extended ZZ conformation is preferred, while in the N-methyl derivative, the folded EE conformation with cofacial phenyl rings is preferred. This conformational switch is likely driven by a combination of steric and electronic factors.
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