Abstract
8-Oxyguanosine 5'-mono-, 5'-di- and 5'-tri-phosphate were synthesized from 2', 3'-O-isopropylidene-8-oxyguanosine by the phosphorylation with P1-diphenyl, P2-morpholinopyrophosphoro chloridate, follwed either by acidic removal of the protecting group, reaction with inorganic phosphate in the presence of DCC, or by the reaction of its morpholidate with pyrophosphate. 5'-Monophosphate was hydrolyzed by the catalysis with snake venom 5'-nucleotidase. 8-Oxyguanosine 2', 3'-cyclic phosphate, which was obtained by the direct phosphorylation method from 5'-O-acetyl-8-oxyguanosine, was completely resistant against pancreatic RNase and RNase T1. Deamination of 8-oxyguanosine and its monophosphate was investigated. In the presence of excess nitrous acid a rapid loss of ultraviolet absorption was observed. With the use of limited amount of nitrous acid, uric acid 9-riboside 5'-monophosphate was obtained.
