First synthesis of L-enantio-uracil dinucleotide.

L-Enantio-uracil dinucleotide, which consists of two L-uridylic acids and one pyrophosphate, was synthesized for the first time in our laboratory. Benzolyated L-uridine was prepared by a steroselective glycosylation of silylated uracil with L-1-acetoxy-2,3,5-tri-O-benzoylribose (L-ABR). After deprotection, L-uridine was converted to L-UP4U by the treatment of L-UMP morpholidate with triethyammonium pyrophosphate (TEA-PPi). Spectral data of synthesized L-UP4U are given in a reference. All spectral data were identical with those of the D-enantiomer except the optical rotation. It showed a positive value compared to the D-enantiomer having a negative value.