Structural study of 1-(2', 3'-O-isopropylidene-(α-d-allo and -β-l-talofuranosyluron)-5'-cyanohydrin)uracil stereoisomers by NMR spectroscopy and theoretical methods.

A structural study of new diastereoisomeric 5'(R and S)-cyanohydrins nucleosides that are important intermediates for antibiotics and antimycotics, such as polyoxins and nikkomycins, was performed using experimental NMR, theoretical methods and 3D analysis. The structures of these compounds were elucidated, and modeling was based on the conformer with the local minimized energy. The calculated and experimentally determined values are in good agreement (Supporting Information).