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Carbon-13 n.m.r. studies of purines and 8-azapurines in basic aqueous medium

✍ Scribed by Linda Goodrich Purnell; Derek J. Hodgson

Publisher
John Wiley and Sons
Year
1977
Tongue
English
Weight
471 KB
Volume
10
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The ^13^C n.m.r. spectra of a variety of purines and 8‐azapurines have been studied in aqueous basic medium; the shifts were measured using dioxane as reference, and corrected to the TMS scale. The compounds studied include adenine, hypoxanthine, 6‐mercaptopurine, guanine, xanthine, 8‐azaadenine, 8‐azahypoxanthine, 8‐azaguanine, 8‐azaxanthine, and 2‐thio‐8‐azaxanthine. Resonances were assigned using noise‐decoupling, selective deuteration at the 8‐position of purines, and coupled spectra. The general effect of changing from a purine to its 8‐aza analog is to produce a downfield shift of C‐2, C‐5, and C‐6 and an upfield shift of C‐4.

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