Glycerol conformation and the crystal structure of lipids. I. An electron diffraction study of tripalmitin and conformationally fixed analogs.
Transmission electron diffraction is used as a qualitative analytical probe of polymethylene chain packing in three conformationally-restricted analogs of tripalmitin derived from configurational isomers of cyclopentane-1,2,3-triol. The analysis demonstrates that the all trans "tuning-fork" conformation seen in X-ray crystal structure analyses on homologous compounds is also found in microcrystals, in contrast to a proposal by Fringeli et al. (Z. Naturforsch. 27b, 780 [1972]) that an all cis conformation of the triglyceride exists in solvent-grown microcrystals and in multilayers. The presence of mixed polymorphs is also shown for bulk samples previously examined by X-ray powder diffraction techniques by other workers.
D003461:Crystallography; D004583:Electrons; D005990:Glycerol; D008968:Molecular Conformation; D010169:Palmitic Acids; D013329:Structure-Activity Relationship; D014280:Triglycerides
D010169:Palmitic Acids; D014280:Triglycerides; D005990:Glycerol