Carbafuranoses

The importance of the carbafuranoses stems from the interest in having access to carbocyclic analogues of nucleosides [88], which have attracted particular attention as anti-tumor and anti-viral agents, (-)-carbovir being one of the more popular synthetic target molecules [89]. (Fig. 1)... 

According to the classical sugar classification, this Chapter is subdivided into five sections carbaaldofuranoses (2.1), carbaketofuranoses (2.2), unsaturated carbafuranoses (2.3), aminocarbafuranoses (2.4) and thiocarbafuranoses (2.5). 

An example highlighting this synthetic tactic is outlined in Scheme 3, where 4a-carbafuranoses 20, 21 and 22, 23 were the chosen target compounds [7b,c]. The opening move was the BF3-assisted vinylogous... 

Carbafuranoses possessing an unsaturation between C4 and C4a positions are often exploited as scaffolds for the assembly of nucleoside carba-analogues related to the neplanocin family, many of which exhibit attractive antiviral properties [2]. 

Apart from a short communication [18] where carbafuranose mercapto derivatives were prepared to be used as intermediates in the formal synthesis of certain carbanucleosides, only one report has been published dealing with the synthesis of thiocarbafuranoses [7c]. 

Gallos, J.K. et al. Facile Synthesis of Enantiomerically Pure Carbafuranoses Precursors of Carbocyclic Nucleosides. 2.1 2001 [120]... 

Rassu, G, Auzzas, L, Pinna, L, Zambrano, V, Battistini, L, Zanardi, F, Marzocchi, L, Acquotti, D, Casiraghi, G, Variable strategy toward carbasugars and relatives. 2. Diversity-based s3mthesis of beta-D-xylo, beta-D-ribo, beta-L-arabino, and beta-L-lyxo 4a-carbafuranoses and (4a-carbafuranosyl)thiols, J. Org. Chem., 66, 8070-8075, 2001. 

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