Abstract
Formycin, showdomycin, pyrazomycin, oxazinomycin are known as C-nucleoside antibiotics. In this review, synthetic methods of C-nucleosides are cited. Especially, synthetic studies on C-nucleoside analogs are summarized.
Aldoses are reacted with carbonyl reagents or diamines and further cyclization affords C-nucleoside analogs. Ethynyl derivatives of sugar are cyclized with cycloaddition reaction to obtain heterocycles. On one hand, Schiff bases or diazo- compounds of sugar also cyclized with acetylenic compounds. Ketoisothiocyanate of sugar derivative is reacted with nucleophilic reagents to give C-nucleoside analogs. Sugar lactones react with lithiated compounds to afford 1'-hydroxy C-nucleo-side analogs under stereoselective control.
