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Synthese von Azaanalogen der Ascorbinsäure und der Isoascorbinsäure
Author(s) -
Stachel HansDietrich,
Zeitler Klaus,
Lotter Hermann
Publication year - 1994
Publication title -
liebigs annalen der chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0170-2041
DOI - 10.1002/jlac.199419941113
Subject(s) - chemistry , ascorbic acid , aldol reaction , adduct , catalysis , derivative (finance) , stereochemistry , medicinal chemistry , organic chemistry , food science , financial economics , economics
Synthesis of Azaanalogues of Ascorbic Acid and Isoascorbic Acid The synthesis of the hitherto unknown azaanalogues of ascorbic acid (±)‐ 10b and isoascorbic acid (±)‐ 10a is described. The aldol‐type reaction of the tetramic acid derivative 4 with benzyloxyacetaldehyde gives rise to a mixture of the adducts (±)‐ 5a and (±)‐ 5b . By X‐ray analysis 5b proved to represent the threo isomer. Catalytic debenzylation of both adducts 5 to the glycols 9 was successful only with 5a leading to 9a . On the other hand, both isomers (±)‐ 9a and (±)‐ 9b have been obtained from the aldols 6a/6b by successive debenzylation and desilylation. Removal of the remaining protective group from 9a/9b yielded racemic N ‐benzylazaisoascorbic acid and racemic N ‐benzylazaascorbic acid, respectively.