首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Nitrosation of Sugar Oximes: Preparation of 2‐Glycosyl‐1‐hydroxydiazene‐2‐oxides
Abstract:Oximes of glucose, xylose, lactose, fructose, and mannose have been prepared. Nitrosation of the oximes of glucose, xylose, and lactose with NaNO2/HCl afforded 2‐(β‐glycopyranosyl)‐1‐hydroxydiazene‐2‐oxides, which were isolated as salts 13 , 22 , and 28 . Nitrosation of fructose oxime 29 furnished fructose, whereas nitrosation of mannose oxime 30 with NaNO2/HCl afforded the 1‐hydroxy‐2‐(β‐d‐ mannopyranosyl)diazene‐2‐oxide 32 , from which the p‐anisidinium salt 31 and the sodium salt 33 were prepared. However, nitrosation of 30 with isopentyl nitrite in aqueous solutions of CsOH or KOH resulted in the formation of the 2‐(α‐D ‐mannofuranosyl)‐1‐hydroxydiazene‐2‐oxide salts 34 and 35 , respectively. Methylation of the ammonium 2‐(β‐D ‐glucopyranosyl)‐1‐hydroxydiazene‐2‐oxide 13 yielded the 1‐methoxy compound, which was benzoylated to afford the tetra‐O‐benzoate 14 a , the structure of which was confirmed by X‐ray diffraction analysis. From the glucose O‐methyloximes 15 and 16 the N‐methoxy‐N‐nitroso‐2,3,4,6‐tetra‐O‐acetyl‐β‐D ‐glucopyranosylamine 18 was prepared. The structure of this compound was confirmed by X‐ray diffraction analysis. Treatment of acetobromoglucose with cupferron furnished the 1‐(2,3,4,6‐tetra‐O‐acetyl‐β‐D ‐glucopyranosyloxy)‐2‐phenyldiazene‐2‐oxide 20 .
Keywords:carbohydrates  glycosyl oximes  nitrosation  NO donors  X‐ray diffraction
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号