Synthesis of Purinyl homo-Carbonucleoside Derivatives of 2-Benzylcyclopenta[c]pyrazol

Abstract

The first members of a new class of carbocyclic nucleoside analogs were synthesized via key intermediate (±)-(cis)-2-bencylcyclopenta[c]pyrazole-4,6-dimethanol, which was obtained from the easily prepared starting compound (±)-(exo,exo)-5,6-isopropylidenedioxy-4,5,6,7-tetrahydro-4,7-methano-2H-indazole by a reaction sequence in which the key step was a one-pot oxidative cleavage of glycol 9 and reduction of the resulting dialdehyde with NaBH₄. Purine moieties were coupled by nucleophilic displacement following mesylation of the latter. The new compounds 15 and 17 are active against cytomagalovirus and varicella-zoster virus at subcytotoxical concentrations.

methanoindazoles - purinyl carbonucleosides - antiviral activity - benzylcyclopenta[c]pyrazol - glycol cleavage

References

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