143730-06-7Relevant articles and documents
Single crystal X-ray structures of the two 4-heptadecyl derivatives of (1R,5S)-3,6,8-trioxabicyclooctane
Moring, Jill,Duclos, Richard I.,Zhang, Jian-Hua,Herbette, Leo G.,Xie, Xiangqun,Makriyannis, Alexandros
, p. 99 - 112 (2007/10/02)
The single crystal structures of the two diastereomeric 4-heptadecyl derivatives of (1R,5S)-3,6,8-trioxabicyclooctane have been determined by X-ray diffraction to be (1R,4R,5S)-heptadecyl-3,6,8-trioxabicyclooctane (I) and (1R,4S,5S)-4-heptadecylooctane (II), respectively, which have an exo or axial 4-heptadecyl group, and an endo or equatorial 4-heptadecyl group, respectively.The structures of I and II had been suggested by their phase-sensitive 2D NOESY 1H-NMR spectra, but are now established unambiguously.These optically pure non-ionic lipid-like amphipathic molecules (I and II) represent the first 3,6,8-trioxabicyclooctanes for which single crystal structures have been solved.Crystals of both isomer I and isomer II were orthorhombic with space group P212121 and had unit cell dimensions of a = 9.586, b = 43.14, c = 5.289 Angstroem, and a = 7.34, b = 51.8, c = 5.636 Angstroem, respectively.The structures of I and II were both solved by using direct methods to R = 0.045 and R = 0.086, respectively.Both I and II pack in stacked bilayers with interdigitating and tilting hydrocarbon chains.The molecular and hydrocarbon cross sections are I: S = 50.70 Angstroem2, Σ = 19.00 Angstroem2 ; and II: S = 41.37 Angstroem2, Σ = 18.26 Angstroem2.Keywords: (1R,4R,5S)-4-heptadecyl-3,6,8-trioxabicyclooctane; (1R,4S,5S)-4-heptadecyl-3,6,8-trioxabicyclooctane; X-ray; Crystal structure; Molecular packing; Nonionic amphiphile
