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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Branched [n]rotaxanes (n = 2-4) from multiple dibenzo-24-crown-8 ether wheels and 1,2-bis(4,4'-dipyridinium)ethane
Stephen J Loeb1, David A Tramontozzi
1Department of Chemistry and Biochemistry, University of Windsor, Ontario, Canada. loeb@uwindsor.ca
Abstract:
To investigate the possibility of incorporating the 1,2-bis(pyridinium)ethane[subset or is implied by]24C8 [2]pseudorotaxane motif into dendrimer like macromolecules, a series of branched [n]rotaxanes were prepared employing multiple dibenzo-24-membered crown ether wheels with various aromatic core structures and the 1,2-bis(4,4'-dipyridinium)ethane axle. Yields of branched [2]-, [3]- and [4]rotaxanes were dependent on the size of the core and the relative proximity of the crown ethers arranged around the core unit.
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