Synthesis of D-fructose-derived spirocyclic 2-substituted-2-oxazoline ribosides
نویسندگان
چکیده
The TMSOTf-mediated synthesis of β-configured spirocyclic 2-substituted-2-oxazoline ribosides was achieved using a "Ritter-like" reaction in toluene through nucleophilic addition of electron-rich nitriles to the oxacarbenium ion intermediate of 1,2;3,4-di-O-isopropylidene-β-D-psicofuranose derivatives with concomitant intramolecular trapping of the C2 hydroxymethyl group on the electrophilic nitrilium carbon. These carbohydrate-derived spirooxazolines are stable and were obtained in good yield with high stereoselectivity due to the conformational rigidity imparted by the 3,4-isopropylidene group.
منابع مشابه
On the utilization of D-fructose for pentose synthesis in Escherichia coli.
The major portion of the ribose and deoxyribose of the RNA and DNA of Escherichia coli does not arise from the oxidative pathway leading from hexose to pentose.1l3 At least 70 per cent of the pentose arises from nonoxidative pathways in which glucose is converted to triose by the Embden-Meyerhof pathway.4 Triose, in the form of glyceraldehyde 3-phosphate, then receives a two-carbon unit from a ...
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