Carbocyclic nucleosides, synthesis, literature

The previously described 7-deazapurine carbocyclic nucleoside synthesis (see Scheme 1) indicated that the most efficient route to 22 would be via reaction of the protected chiral amine 23 with the dimethylacetal of 2-(2-amino-4,6-dichloropyrimidin-S yl)acetaldehyde followed by ring closure, hydrolysis and dqirotection. A review of the literature revealed two enantioselective routes to cyclobutyl derivatives that had been used in the chiral synthesis of carbocyclic oxetanocins and could be employed for preparing a precursor to 23. In one case, however, the initial step involved a [2-i-2]-cycloaddition reaction of not easily obtainable reagents in the presence of a chiral titanium compound as... 

The literature until the end of 1993 on the synthesis of carbocyclic nucleosides has been reviewed. 1 1... 

The present review complements and concludes the first part [97-AHC(68)223], which was devoted to the chemistry of C-nucleosides of hetero monocyclic bases. C-Nucleosides reviewed in this part were systematized according to the size and complexity of the base component, starting with those of simpler base components followed by more complex ones. Within a class of a particular base component, the arrangement also goes from less to more complex attached components. The C-nucleosides of a certain category are discussed first, followed by their analogs in the sequence homo, carbocyclic, reverse, and acyclo C-nucleosides [for definitions, see Part I, 97AHC(68)223]. To avoid redundancy, whenever the synthesis of a C-nucleoside of a condensed base comprised the elaboration of a C-nucleoside of a monocyclic base, the synthesis of the latter is usually not discussed, since it has already been mentioned in the first part of this review. The literature has been surveyed to Vol. 125, No. 7 (1996), of Chemical Abstracts and Vol. 142 No. 10 (1996), of the Index Chemicus. 

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