X-Ray and Neutron Diffraction Crystallography

Specific X-ray crystal structures have been reported as follows (solvent molecules of crystallization are frequently not reported). 

2 Glycosides, Disaccharides and Derivatives Thereof. - Penta-O-benzoyl-a-D-fructofuranose adopts an E2 configuration. An X-ray of methyl a-D-arabinofuranoside bound to concanavalin A has been reported.  

Peracetylated derivatives the plant hormone-related 2-(indol-3-yl)-ethyl and 2-phenylethyl P-D-xylopyranosides 1 and 2 respectively 2-(indol-3-yl)ethyl P-D-galactopyranoside tetraacetate, related to the plant hormone auxin. Structural analysis was also assisted by NOE NMR experiments peracetates of (2S)-butyl 6-0-(P-D-apiofuranosyl)-P-D-glucopyranoside glycosides isolated from cassava Manihot esculentd)P  

The disaccharides a-D-galactopyranosyl a-D-galactopyranoside, a-D-allopyr-anosyl a-D-allopyranoside, 3,3, 4,4 -tetra-0-benzoyl-2,2, 6,6 -tetradeoxy-a,a-ribotrehalose 3, 2,3,4,6,r,3, 4, 6 -octa-0-acetyl-P-sophorose, methyl 2,3,4,6,3, 4, 6 -hepta-0-acetyl-P-sophoroside, methyl 2,3,4,6,3, 4 -hexa-0-acetyl-6 -deoxy-P-sophoroside and methyl 2-0-(2,3,4-tri-0-acetyl-P-D-xylopyranosyl)-3-0-benzyl-4,6-O-benzylidene-a-D-mannopyranoside 4.  

The trehalose derivatives 3-0-benzyl-4,6-0-benzylidene-2-deoxy-a-D-ri/ o-hexopyranosyl 4, 6 -0-benzylidene-2 -deoxy-a-D-rifto-hexopyranoside and 2,2, 3,3 -tetra-0-benzoyl-6,6 -dideoxy-4,4 -di-0-mesyl-6,6 -dithiocyanato-a,o-tre-halose di-iV-acetylchitobiose complexed to turkey egg lysozyme.  

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Direct Methods. X-ray or neutron diffraction crystallography can determine the crystal symmetries (translational and often even local). But X-ray beams or neutron beams are not phase-coherent, so much information is lost. There are, however, many significant relationships between the intensities of the diffraction peaks. 

In macromolecular crystallography, this process cannot be observed because hydrogen atoms are not located and dynamic processes cannot be seen . However, in the crystal structure of vitamin B12 studied by X-ray and neutron diffraction methods, an interpretation of the water movement could be derived [127, 880, 881]. 

Bacon, G. E., ed. X-Ray and Neutron Diffraction. New York Pei amon Press, 1966. This book, part of a series intended to introduce undergraduates to important topics in physics through original sources, treats diflraction techniques as the culmination of a long tradition in crystallography. 

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