Carbasugars analogues

S.-K. (2009) Chemoenzymatic syntheses of carbasugar analogues of nucleoside diphosphate sugars UDP-carba-Gal, UDP-carba-GlcNAc, UDP-carba-Glc, and GDP-carba-Man. Chem. Commun. (Cambridge, U.K.), 1733-1735. 

In the three major sections of this article, the most representative syntheses of the carbasugars and their closest analogues are analyzed, and the key carbocycle forming manoeuvres are focused on in particular detail. Reference to the observed biological activity is also included, where sufficient data is available. Only recent literature from the 90s onwards was considered, although the most pioneer works on this matter have also been remembered. 

Carbocyclic analogues of furanoid sugars have represented a relevant topic in the realm of carbasugars ever since the discovery of their occurrence as substructures in natural bioactive compounds, such as carbocyclic nucleosides and certain carbocyclic sugar conjugates [2], at... 

As an example (Scheme 12), exposure of racemic 72 to sodium methoxide resulted in a smooth fragmentation of the norbomyl backbone to achieve olefinic methyl ester 73, whose elaboration then afforded densely functionalized cyclopentane framework 74. Sodium acetate-mediated displacement of the iodo functionality within 74, followed by elimination of the mesylate group and base-promoted deacetylation finally provided the unsaturated carbasugar 75, which nicely served as a building block for the preparation of a set of neplanocin analogues. 

In the past, ketose-type pyranose carbasugars were mainly investigated in the search for sucrose mimics to employ as non-nutritive sweeteners [25a,b]. Probably due to this seemingly unappealing potential and the inherent difficulties related to their stereoconstitutional features, up until 1990 only one report was found to have been published dealing with the asymmetric synthesis of D- and L-carba-analogues of fructopyranose [34]. 

Table 1. Recent Reviews and Accounts about Carbasugars and Their Analogues...

Advances in Chemical Synthesis of Carbasugars and Analogues GLORIA RASSU, LUCIANA AUZZAS, LUIGI PINNA,... 

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