Synthesis, NMR studies and theoretical calculations of novel 3-spiro- branched ribofuranoses

Article abstract of DOI:10.1016/S0040-4020(99)00696-1

Novel spiro-branched sugar derivatives bearing a spiro-5'-(4'-amino-2'- oxazolone) or a spiro-5'-(4'amino-1',2',3'-oxathiazole-2',2'-dioxide) rings at position-3 of the sugar moiety have been prepared. The synthesis has been achieved by a one-pot procedure from a conveniently protected sugar cyanohydrin derivative by reaction with chlorosulfonyl isocyanate or sulfamoyl chloride, respectively. The tautomerie preference in solution of these novel 3-spiro sugars are described as derived from NMR spectroscopy. Also a comparative theoretical study, by ab-initio methods, of the steric and electronic properties of the spiro rings present in these sugar derivatives has been performed.