Syntheses of Diamino‐dideoxylyxose Derivatives using Acylnitroso Dienophiles

Abstract

N-Acylnitroso derivatives 6 which were prepared by in-situ oxidation of the corresponding hydroxamic acids 5 reacted instantaneously and in high yields with dihydropyridine 4. The Diels-Alder adducts 8 were formed rcgiospecifically with the acylnitroso dienophiles 6a<, whereas the dienophiles 6d f gave mixtures of both regioisomers 7 and 8. These and some other results [2] were best explained by the FMO theory. The Diels-Alder adducts 7 and 8 gave the corresponding 'unti'-&-glycols when reacted with Os04/N-methylmorpholine N-oxide. Hydrogcnolysis of the N-O bond followed by peracetylation led to the expected aminolyxose derivatives 14 and 16. A similar sequence, using 4 and the hydroxamic-acid derivative 18 of (+)-D-mandelic acid led, with a poor asymmetric induction, to a mixturc of the expected optically active aminolyxose compounds 19A/19B.

Stereo- and regioselectivity of the hetero-Diels–Alder reaction of nitroso derivatives with conjugated dienes

“…The application of amino acids as inducers of stereoselectivity (D- and L- O -methylproline or D- and L-mandelic acid) resulted in only modest stereoselectivity [107–111]. In 1996, Streith and Defoin published a successful asymmetric induction by reacting cyclohexa-1,3-diene ( 120 ) with the acylnitroso dienophile 119 (Scheme 24) [10].…”

Hydroxamates as Substrates and Inhibitors for FMN-Dependent 2-Hydroxy Acid Dehydrogenases

“…The synthesis was carried out in two steps according to (31), with an overall yield of 40%. 1 Enzymatic assays.…”

Regio‐ and Stereochemical Studies on the Nitroso‐Diels–Alder Reaction with 1,2‐Disubstituted Dienes

“…The asymmetric version of the nitroso-Diels-Alder reaction has also been the subject of intense scrutiny, leading to the design of several chiral reagents with high levels of stereoinduction, [5][6][7] and culminating in the achievement of the catalytic asymmetric nitroso-Diels-Alder reaction of 2-pyridylnitroso derivatives by using a chiral copper(I) complex [8] These recent results have played an important role in the renewed interest for this reaction and its synthetic applications.…”