Premium
Desoxy‐nitrozucker. 2. Mitteilung Herstellung geschützter 1‐Desoxy‐1‐nitroaldosen
Author(s) -
Aebischer Bernard,
Vasella Andrea,
Weber HansPeter
Publication year - 1982
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19820650302
Subject(s) - chemistry , derivative (finance) , oxime , pyranose , stereochemistry , nitro , halogenation , anomer , medicinal chemistry , organic chemistry , alkyl , financial economics , economics
Synthesis of Protected 1‐Deoxy‐1‐nitroaldoses The direct oxidation of the oxime 1 with t ‐butyl hydroperoxide and vanadyl acetylacetonate yielding the nitro derivative 2 (54%, Scheme 1 ) could not be applied to other oximes. Diastereoselective bromination of the aldonolactone oxims 7 and 10–12 according to known procedures gave the corresponding bromonitroso compounds which were oxidized to the bromonitro compounds 9, 14, 18 and 22 , respectively. Oxidation of the bromonitroso compound in the D‐mannopyranose series proved difficult, but the corresponding chloronitro derivative 23 was easily obtained according to Corey & Estreicher ( Scheme 2 and 3 ). The structure of the bromonitro compound 9 was determined by an X‐ray analysis, and the configurations of the bromonitro compounds 14, 18 and 22 were deduced from their molecular rotations. Reduction of the bromonitro compounds gave the protected 1‐deoxy‐l‐nitroaldoses 2 , 15/16 , 19/20 , and 24/25 , respectively, in good overall yields. The ribose derivatives 15 and 16 were detritylated to give the nitro compound 4 , and the mannose derivative 2 was partially deprotected to give the monoisopropylidene compound 26 . The nitro group shows a normal anomeric effect which is reflected in the IR . spectra of the pyranose derivatives 19 and 20 , and 24 and 25 .