A series of nucleoside dialdehydes have been obtained as powders after treatment of various adenine nucleosides with paraperiodic acid. Thus, oxidation gave dialdehydes derived from adenosine (1), 9-α-d-mannopyrano-syladenine (2), 9-(5-deoxy-α-d-arabinofuranosyl)adenine (3), 9-α-l-rhamnopyranosyladenine (4), 9-β-l-fucopyranosyl-adenine (5), 9-β-d-fucopyranosyladenine (6), 9-α-d-arabi-nopyranosyladenine (7), 9-β-d-ribopyranosyladenine (8), and 9-(5-deoxy-β-d-erythro-o-pent-4-enofuranosyl)adenine (9). Nucleoside dialdehydes 1-3 and 6-8 were weak substrates for adenosine aminohydrolase from calf intestinal mucosa. Di-aldehyde 8 had the strongest affinity, but 1 had the highest Vmax. All of the dialdehydes except 5 were inhibitors of the enzyme. The best inhibitors were 9 (K1 = 4 μM) and 4 = 28 μM), and neither were substrates. The inhibitors did not exhibit time-dependent inhibition and did not appear to form covalent bonds with the protein. The data strongly suggest that the active form of the dialdehydes is as the open-chain dihydrates. The alcohol obtained by reduction of 9 (compound 10) was the strongest inhibitor (K1 = 0.9 μM) among the related alcohols and the nucleoside dialdehydes. © 1979, American Chemical Society. All rights reserved.
