Abstract:
:Purine nucleoside analogs modified by replacement of the nitrogen atom at the 3 position by a CH group give a characteristic circular dichroism curve that is not substantially modified by chemical substitution at the 8 position. Since it is rather well established that 8-substituted purine nucleosides are predominantly in the syn conformation in aqueous solution, it follows that the 3-deazapurine nucleosides, whether substituted at position 8 or not, also favor the syn conformation. These data are in sharp contrast to the circular dichroism data obtained on 8-halogenated and 8-alkylated derivatives of adenosine and guanosine, which give circular dichroism profiles substantially different from those obtained on the parent compounds. Certain purine-nucleoside-utilizing enzymes fail to interact effectively with either the unsubstituted 3-deaza analogs or the 8-substituted derivatives of adenosine and guanosine. The hypothesis recently given that the inactivity of the 8-substituted derivatives springs from their syn-conformational preference is tentatively accepted to explain the inactivity of the 3-deaza analogs.
journal_name
Proc Natl Acad Sci U S Aauthors
Miles DW,Townsend LB,Redington P,Eyring Hdoi
10.1073/pnas.73.7.2384keywords:
subject
Has Abstractpub_date
1976-07-01 00:00:00pages
2384-7issue
7eissn
0027-8424issn
1091-6490journal_volume
73pub_type
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