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Updated: May 15, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
5,7,8,10,11,13,14,16-Octa-hydro-6,15-(ethanoxyethanoxyethano)-1,4:17,20-dietheno[9,12,6,15]benzodioxadiaza-cyclo-doco
Heath A Barnett1, Frank R Fronczek, Steven F Watkins
1Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803-1804, USA.
Abstract:
The title compound, C(32)H(40)N(2)O(4), is a 1,10-diaza-18-crown-6 cryptand with an o-terphenyl bridge. In the polyether ring, two adjacent -CH(2)- groups are disordered with very nearly equal populations of two conformers. The ordered bond lengths are normal, with average C-C = 1.511 (3) Å, C-O = 1.421 (3) Å, and C-N = 1.466 (4) Å. The r.m.s. deviations of the three rings of the terphenyl bridge vary from 0.007 to 0.009 Å and the two rings ortho to one another are twisted by 50.75 (5) and 47.76 (4)° with respect to the third ring. The N⋯N distance is 5.408 (1) Å.
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