A simple method for the preparation of ‘ribonucleoside dialdehydes’ and some comments on their structure

Abstract

Adenosine, guanosine, inosine, cytidine, and uridine have been oxidised with periodate to give the respective α-substituted derivatives of α′-hydroxymethyloxydiacetaldehyde (‘ribonucleoside dialdehydes’). These have been isolated by a simple procedure which involves extraction with ethanol, thus separating the dialdehydes from inorganic material. The compounds so isolated are more stable than has been suggested by early work in this field. I.r. and n.m.r. spectroscopy show that the compounds contain few if any free aldehyde groups. They appear to be mixtures of hydrated forms although they run as single spots on t.l.c. in several solvent systems. Dried samples also contain virtually no aldehyde groups, and the possibility that they are polymeric structures as suggested by others, is discussed. With the exception of ‘guanosine dialdehyde,’ the amplitude of the Cotton effect in the o.r.d. spectrum is less than that in the parent ribonucleoside.