Formation of Higher-membered Nitrogen Heterocycles

Seven-membered heterocycles containing one nitrogen atom may be obtained either from 105 (see p. 376) or 6-amino-6-deoxy-D-glucose (227) by reduction122 to 228, or from 6-azido-6-deoxy-D-glucopyranose (229) by oxidation to 230 followed by reduction of 230 to 231. A 

Anhydronucleosides in which an oxygen or nitrogen atom of the base is involved in ring formation with C-5 constitute examples of formation of large heterocyclic rings.312,329 333 Thus, 235 gives 236, and 237 gives 238. 

Department of Chemical Pathology, St. Mary s Hospital Medical School, London, W. 2, England 

Linkages in which 2-Acetamido-2-deoxy-D-galactose is Linked 

0-/3-D-Xylosy]-L-serine as a Carbohydrate-peptide Linking Moiety...434 

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